Refactor the yaml data package to group data sources by category

be composed per report type

.gitignore

@@ -1,5 +1,6 @@
-# Compiled application binary
-weatherreporter
+# Compiled application binary and testing workspace
+/weatherreporter
+/workspace
 
 # ---> Go
 # If you prefer the allow list template instead of the deny list, see community template:
@@ -71,4 +72,3 @@ Icon
 Network Trash Folder
 Temporary Items
 .apdisk
-

.woodpecker/release.yml

@@ -0,0 +1,50 @@
+when:
+  - event: tag
+
+steps:
+  - name: build-release-assets
+    image: golang:1.25
+    commands:
+      - |
+        set -eu
+
+        version="$CI_COMMIT_TAG"
+        dist="dist"
+        pkg="gitea.maximumdirect.net/eric/weatherreporter/cmd/weatherreporter"
+
+        rm -rf "$dist"
+        mkdir -p "$dist"
+
+        build_binary() {
+          goos="$1"
+          goarch="$2"
+          suffix="$3"
+          output="$dist/weatherreporter-$version-$goos-$goarch$suffix"
+
+          CGO_ENABLED=0 GOOS="$goos" GOARCH="$goarch" \
+            go build -trimpath -ldflags "-s -w -X gitea.maximumdirect.net/eric/weatherreporter/internal/buildinfo.Version=$version" \
+            -o "$output" "$pkg"
+        }
+
+        build_binary linux amd64 ""
+        build_binary linux arm64 ""
+        build_binary darwin amd64 ""
+        build_binary darwin arm64 ""
+        build_binary windows amd64 ".exe"
+        build_binary windows arm64 ".exe"
+
+  - name: publish-release
+    image: woodpeckerci/plugin-release
+    depends_on:
+      - build-release-assets
+    settings:
+      api_key:
+        from_secret: GITEA_RELEASE_TOKEN
+      files:
+        - dist/weatherreporter-*
+      checksum: sha256
+      checksum-file: SHA256SUMS
+      checksum-flatten: true
+      file-exists: skip
+      overwrite: false
+      prerelease: false

README.md

@@ -1,2 +1,22 @@
 # weatherreporter
 
+`weatherreporter` is a Go application for preparing human-facing weather
+reports from normalized forecast data. It builds JSON module snapshots, passes
+YAML prompt data packages to `scriptorium`, and keeps inspectable artifacts
+under a local workspace. It can also upload successfully generated managed
+Markdown reports to a configured `distributor` HTTP upload endpoint.
+
+## Quickstart
+
+```sh
+weatherreporter generate daily --date 2026-05-29 --out ./daily.md
+```
+
+## Documentation
+
+- [CLI reference](docs/cli.md)
+- [Configuration reference](docs/config.md)
+- [Operations guide](docs/operations.md)
+- [Troubleshooting](docs/troubleshooting.md)
+- [Architecture policy](docs/policy/architecture.md)
+- [Development policy](docs/policy/development.md)

cmd/weatherreporter/main.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/cli"
+)
+
+func main() {
+	if err := cli.Run(context.Background(), os.Args[1:], os.Stdout, os.Stderr); err != nil {
+		fmt.Fprintf(os.Stderr, "weatherreporter: %v\n", err)
+		os.Exit(1)
+	}
+}

docs/cli.md

@@ -0,0 +1,102 @@
+# Weatherreporter CLI
+
+`weatherreporter` generates Markdown weather reports, runs scheduled report
+batches, and inspects stored artifacts.
+
+## Shortest Useful Command
+
+```sh
+weatherreporter generate daily --date 2026-05-29 --out ./daily.md
+```
+
+This loads configuration, fetches weather data, writes managed workspace
+artifacts, runs `scriptorium render` as a preflight check, runs
+`scriptorium run`, and writes an extra Markdown copy to `./daily.md`. If
+distributor notification is enabled in configuration, the command also uploads
+the managed Markdown report after final metadata is saved.
+
+## Commands
+
+```text
+weatherreporter --help
+weatherreporter generate daily [--config PATH] [--units VALUE] [--tz NAME] [--out PATH] [--date YYYY-MM-DD]
+weatherreporter generate tomorrow [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+weatherreporter generate three-day [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+weatherreporter generate weekend [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+weatherreporter generate storm [--config PATH] [--units VALUE] [--tz NAME] [--out PATH] --start TIME --end TIME
+weatherreporter run morning [--config PATH] [--units VALUE] [--tz NAME] [--out-dir PATH]
+weatherreporter run evening [--config PATH] [--units VALUE] [--tz NAME] [--out-dir PATH]
+weatherreporter inspect reports [--config PATH] [--limit N]
+weatherreporter inspect metadata [--config PATH] RUN_ID
+weatherreporter inspect modules [--config PATH] RUN_ID
+weatherreporter inspect data-package [--config PATH] RUN_ID
+weatherreporter inspect prior [--config PATH] RUN_ID
+weatherreporter inspect sources [--config PATH] RUN_ID
+```
+
+`generate` commands write a JSON module snapshot, YAML data package, preflight
+artifact, managed Markdown report, and metadata under the configured workspace.
+`--out` writes an extra Markdown copy for the operator; distributor
+notification uses the managed report path, not the extra copy. `generate storm`
+requires explicit event-window bounds with `--start` and `--end`.
+
+`run morning` generates Daily Today and the 3-Day Outlook, plus Weekend Outlook
+except on Sunday. `run evening` generates the Tomorrow Planning Brief. Batch
+runs continue independent reports after a failure, print a JSON summary to
+stdout, write compact status lines to stderr, and return nonzero when any report
+failed. `--out-dir` writes extra Markdown copies for the operator; distributor
+notification uses each managed report path, not the extra copies. When
+notification is enabled, batch summaries and status lines include notification
+status, accepted distributor run ID, or notification error fields for each
+attempted report.
+
+`inspect` commands read existing workspace artifacts and emit JSON to stdout.
+They do not fetch weather data or invoke `scriptorium`.
+
+## Flags
+
+- `-h`, `--help`: show help.
+- `--config PATH`: load configuration from `PATH` instead of `/usr/local/etc/weatherreporter/config.yml`.
+- `--units VALUE`: override configured Weather API units for `generate` and `run`.
+- `--tz NAME`: override configured Weather API timezone for `generate` and `run`.
+- `--out PATH`: write an extra Markdown report copy for `generate` commands.
+- `--out-dir PATH`: write extra Markdown report copies for `run morning` and `run evening`.
+- `--date YYYY-MM-DD`: optional date for `generate daily`; defaults to the current local date in the configured timezone.
+- `--start TIME`: required start time for `generate storm`.
+- `--end TIME`: required end time for `generate storm`.
+- `--limit N`: maximum records for `inspect reports`; defaults to `20`, and `0` means no limit.
+
+Storm times accept `YYYY-MM-DDTHH:MM` in the configured timezone or RFC3339
+timestamps with explicit offsets.
+
+Distributor notification is configured only through `notify.distributor`; there
+are no distributor-specific CLI flags.
+
+## Common Workflows
+
+```sh
+weatherreporter generate tomorrow --out ./tomorrow.md
+weatherreporter generate three-day --out ./three-day.md
+weatherreporter generate weekend --out ./weekend.md
+weatherreporter generate storm --start 2026-05-29T18:00 --end 2026-05-30T06:00 --out ./storm.md
+weatherreporter run morning --out-dir ./reports
+weatherreporter run evening --out-dir ./reports
+```
+
+## Inspection
+
+```sh
+weatherreporter inspect reports --limit 10
+weatherreporter inspect metadata 20260529T100000.000000000Z_daily_today
+weatherreporter inspect modules 20260529T100000.000000000Z_daily_today
+weatherreporter inspect data-package 20260529T100000.000000000Z_daily_today
+weatherreporter inspect prior 20260529T100000.000000000Z_daily_today
+weatherreporter inspect sources 20260529T100000.000000000Z_daily_today
+```
+
+`inspect reports` lists recent generated runs with artifact paths and source
+warning counts. The other inspect commands require a RunID. `inspect modules`
+returns the persisted ordered module snapshot for a run. `inspect prior`
+returns the prior comparable snapshot metadata selected from stored metadata, or
+`null` when none exists. `inspect sources` shows source provenance and source
+warnings without dumping full weather payloads.

docs/config.md

@@ -0,0 +1,234 @@
+# Weatherreporter Configuration
+
+Configuration is YAML. By default, `weatherreporter` reads:
+
+```text
+/usr/local/etc/weatherreporter/config.yml
+```
+
+Use `--config PATH` to load a different file. If the default file is absent,
+built-in defaults are used. If `--config PATH` points to a missing file, loading
+fails.
+
+Precedence is:
+
+1. CLI flags
+2. configuration file
+3. built-in defaults
+
+The CLI configuration overrides are `--units` and `--tz`. Output flags control
+report copies for the current command but do not change configuration files.
+Environment variables do not override configuration fields.
+
+## Minimal Config
+
+See [examples/minimal-config.yml](../examples/minimal-config.yml).
+
+```yaml
+weather_api:
+  base_url: https://weather.api.example.com/
+```
+
+`weather_api.base_url` is required for commands that fetch weather data. Other
+fields fall back to defaults.
+
+## Production-Oriented Config
+
+See [examples/config.yml](../examples/config.yml). The example is loaded by the
+config test suite.
+
+## Field Reference
+
+### `weather_api`
+
+- `base_url`: absolute base URL for the Weather API. Required for generation and fetch workflows.
+- `timeout`: HTTP timeout duration. Default: `10s`.
+- `precision`: numeric precision query value. Default: `1`.
+- `units`: Weather API units query value. Default: `us`.
+- `timezone`: report timezone and Weather API timezone query value where supported. Default: `America/Chicago`.
+- `format`: Weather API response format. Must be `json`. Default: `json`.
+
+Timezone values may be IANA names, configured aliases such as `Chicago` and
+`Stl`, US timezone abbreviations, or UTC offsets such as `-5` and `+09:30`.
+
+### `location`
+
+`location` is descriptive prompt context included in module metadata and
+Scriptorium data packages. It does not select a Weather API endpoint or enable
+multiple configured forecast locations.
+
+- `id`: short local identifier. Default: `home`.
+- `name`: human-readable location name. Default: `Brentwood`.
+- `region`: broader forecast area context. Default: `St. Louis Metro`.
+
+The prompt-facing location object also includes `timezone`, derived from the
+effective `weather_api.timezone` after CLI overrides such as `--tz`.
+
+### `secrets`
+
+- `directory`: optional directory of file-backed environment secrets. Default:
+  empty, which disables secret loading.
+
+When configured, each regular file directly under `secrets.directory` is loaded
+after config file parsing and CLI overrides. The file basename must be a valid
+environment variable name matching `[A-Za-z_][A-Za-z0-9_]*`; the file contents
+become the environment variable value and overwrite any existing value. One
+trailing LF or CRLF is stripped. Subdirectories, symlinks, invalid filenames,
+missing directories, and unreadable files fail config loading.
+
+### `notify`
+
+`notify.distributor` controls distributor notification after successful report
+generation. It is disabled by default and does not add CLI flags. When enabled,
+weatherreporter uploads one distributor bundle per generated report after
+`scriptorium run` succeeds and final metadata is saved.
+
+- `enabled`: whether distributor notification config is active. Default:
+  `false`.
+- `endpoint`: absolute distributor endpoint URL. Required when enabled.
+  Default: `https://distributor.example.com`.
+- `token_env`: environment variable name that will contain the distributor
+  upload token. Required when enabled. Default: `DISTRIBUTOR_UPLOAD_TOKEN`.
+- `timeout`: distributor operation timeout. Must be greater than zero when
+  enabled. Default: `30s`.
+- `failure_policy`: must be `error` when enabled. Default: `error`.
+- `pipeline_id_template`: template for the distributor pipeline ID. Required
+  when enabled. Default: empty.
+- `bundle_id_template`: template for distributor bundle IDs. Default:
+  `weatherreporter.{location_id}.{report_id}`.
+- `idempotency_key_template`: template for distributor idempotency keys.
+  Default: `{bundle_id}.{run_id}`.
+- `report_path_templates`: ordered list of templates for Markdown report paths
+  inside the distributor bundle. Each rendered path maps to the same managed
+  Markdown report source. Default:
+  ```yaml
+  - "{valid_start_date}/{artifact_group}/{valid_start_date}-{artifact_group}-{run_id}.md"
+  ```
+
+Supported template variables are `location_id`, `report_id`, `run_id`,
+`artifact_group`, `batch_output_name`, `valid_start_date`, `valid_end_date`,
+`valid_start_time`, `valid_end_time`, `valid_start_stamp`, and
+`valid_end_stamp`. Date values use `YYYY-MM-DD`, time values use `HHMM`, and
+stamp values use `YYYY-MM-DDTHHMM` in the effective report timezone.
+`pipeline_id_template` and `idempotency_key_template` may also use `bundle_id`.
+
+The rendered pipeline ID selects the configured distributor `http_upload`
+workflow. The rendered bundle ID is the stable logical source identity for the
+report stream. The rendered idempotency key is the per-run retry identity.
+
+Rendered report paths must be unique relative paths with `/` separators. They
+must not contain backslashes, empty path segments, `.`, `..`, `manifest.json`,
+or `.distributor.json`.
+
+The upload token is read from the environment variable named by `token_env`
+after config loading and `secrets.directory` processing. Config files should
+name the variable only; they should not contain the token value.
+
+### `missing_source`
+
+- `default`: missing-source behavior for optional sources. One of `error`, `warn`, or `none`. Default: `warn`.
+- `sources`: optional map of source-specific overrides, using the same policy values.
+
+Hourly forecast data is required for generated reports. Optional sources use
+the missing-source policy.
+
+### `scriptorium`
+
+- `binary`: `scriptorium` executable name or path. Default: `scriptorium`.
+- `config_path`: optional Scriptorium config path passed to the adapter.
+- `profile`: optional Scriptorium profile passed to the adapter.
+- `timeout`: subprocess timeout. Default: `2m`.
+- `extra_args`: optional additional arguments passed to Scriptorium commands.
+
+### `workspace`
+
+- `root`: workspace root for managed artifacts. Default: `workspace`.
+- `snapshots_dir`: module snapshot and metadata directory under `workspace.root`. Default: `snapshots`.
+- `reports_dir`: managed Markdown report directory under `workspace.root`. Default: `reports`.
+- `data_packages_dir`: prompt input package directory under `workspace.root`. Default: `data-packages`.
+- `preflight_dir`: Scriptorium render output directory under `workspace.root`. Default: `preflight`.
+- `notifications_dir`: distributor notification debug artifact directory under `workspace.root`. Default: `notifications`.
+
+Workspace subdirectories must be relative paths that stay inside
+`workspace.root`.
+
+### `dayparts`
+
+`dayparts` is a list of named local-time windows used by forecast derivation.
+Each entry has:
+
+- `name`
+- `start`
+- `end`
+
+`start` and `end` use `HH:MM`. The default entries are overnight, morning,
+midday, afternoon, and evening.
+
+### `recent_change`
+
+- `temperature_degrees`: temperature change threshold. Default: `5`.
+- `precip_probability_points`: precipitation probability threshold. Default: `20`.
+- `wind_gust_miles_per_hour`: wind gust change threshold. Default: `10`.
+- `precip_timing_shift_minutes`: precipitation timing shift threshold. Default: `120`.
+
+Recent Changes are added to prompt input when a prior comparable module
+snapshot exists and a threshold is crossed.
+
+### `reports`
+
+`reports` optionally overrides the ordered deterministic modules declared by
+report definitions. Omit a report entry to use its default module order.
+
+Supported report keys are `daily`, `tomorrow`, `three_day`, `weekend`, and
+`storm`. Canonical report IDs such as `daily_today` and `daily_tomorrow` are
+also accepted.
+
+Each report entry supports:
+
+- `deterministic_modules`: ordered module list. Entries may be string module
+  IDs or objects with `id` and optional `options`.
+
+Example:
+
+```yaml
+reports:
+  daily:
+    deterministic_modules:
+      - metadata
+      - current_conditions
+      - narrative_forecast
+      - id: area_forecast_discussion
+        options:
+          sections:
+            - short_term
+      - hourly_forecast
+```
+
+Unknown reports, unknown modules, duplicate modules, incompatible report/module
+combinations, duplicate stanza names, and invalid options fail config loading.
+`area_forecast_discussion.options.sections` may contain `product`,
+`key_messages`, `short_term`, and `long_term`. Empty or omitted `sections`
+includes all available AFD sections.
+
+The module registry accepts all module IDs documented in
+[Module Contract Internals](internal/module.md). Unknown or unimplemented
+module IDs fail validation instead of being skipped.
+
+## Secrets
+
+Configuration files should not contain raw secrets. Use `secrets.directory` to
+load secret values from files into environment variables for integrations that
+read credentials from the environment. Secret file names become environment
+variable names, and secret file contents become values. For distributor
+notification, this allows a file such as
+`<secrets.directory>/DISTRIBUTOR_UPLOAD_TOKEN` to supply the token referenced by
+`notify.distributor.token_env`.
+
+## Maintained Examples
+
+- [examples/minimal-config.yml](../examples/minimal-config.yml): smallest
+  useful config for generation and fetching.
+- [examples/config.yml](../examples/config.yml): production-oriented config
+  covering maintained fields.
+
+Both example files are loaded by the config test suite.

docs/integrations/distributor/api.md

@@ -0,0 +1,136 @@
+# Upstream Producer Integration
+
+Audience: developers and LLM coding agents adding `distributor` support to an upstream Go producer application.
+
+This document is the copyable implementation guide for submitting producer outputs to a `distributor` pipeline whose source backend is `http_upload`.
+
+## Required Inputs
+
+The upstream application needs these values from deployment or operator configuration:
+
+- distributor endpoint: the HTTP server base URL, such as `https://distributor.example.com`;
+- upload token: bearer token that authenticates the producer;
+- pipeline id: configured `http_upload` pipeline that should process this upload;
+- generated files: regular local files to include in the source bundle;
+- bundle id: stable identifier for the logical report stream or artifact;
+- idempotency key: unique key for one producer run, reused only when retrying that same run.
+
+Do not put destination routing, public URLs, transform settings, or credentials in the source manifest. Those belong in the `distributor` pipeline configuration.
+
+The token, pipeline id, bundle id, and idempotency key have different jobs. The token authenticates the producer. The pipeline id selects the configured distributor workflow, including destinations and publishing policy. The bundle id tells `distributor` whether a new upload is a newer version of the same source; keep it stable across runs that should replace the same managed destination artifact. The idempotency key tells `distributor` whether an upload request is a retry; change it for each distinct producer run so new content is enqueued.
+
+## Recommended Workflow
+
+Use `gitea.maximumdirect.net/eric/distributor/pkg/upload`.
+
+For most producers, use `UploadFiles`. It accepts producer-generated files, builds a temporary valid source bundle with `pkg/bundle`, uploads a gzip-compressed tar archive, and removes temporary files when the call returns.
+
+Use `UploadBundle` only when the producer already assembled a complete bundle directory containing `manifest.json`.
+
+Add the dependency from the upstream application:
+
+```sh
+go get gitea.maximumdirect.net/eric/distributor
+```
+
+## Minimal Go Example
+
+```go
+package reports
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"time"
+
+	"gitea.maximumdirect.net/eric/distributor/pkg/bundle"
+	"gitea.maximumdirect.net/eric/distributor/pkg/upload"
+)
+
+func SubmitReport(reportPath, summaryPath string) error {
+	endpoint := os.Getenv("DISTRIBUTOR_UPLOAD_ENDPOINT")
+	token := os.Getenv("DISTRIBUTOR_UPLOAD_TOKEN")
+	if endpoint == "" || token == "" {
+		return fmt.Errorf("distributor endpoint and token are required")
+	}
+
+	pipelineID := "weather-hourly"
+	reportID := "weather.hourly.brentwood"
+	runID := time.Now().UTC().Format("20060102T150405.000000000Z")
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	client, err := upload.NewClient(upload.ClientOptions{
+		Endpoint: endpoint,
+		Token:    token,
+	})
+	if err != nil {
+		return err
+	}
+
+	result, err := client.UploadFiles(ctx, upload.UploadFilesOptions{
+		PipelineID:     pipelineID,
+		ID:             reportID,
+		IdempotencyKey: reportID + "." + runID,
+		Files: []bundle.BundleFile{
+			{SourcePath: reportPath, Path: "report.md"},
+			{SourcePath: summaryPath, Path: "summary.txt"},
+		},
+	})
+	if err != nil {
+		var conflict *upload.IdempotencyConflictError
+		if errors.As(err, &conflict) {
+			return fmt.Errorf("idempotency key was reused for different bundle content: %w", err)
+		}
+		return err
+	}
+
+	fmt.Printf("distributor accepted run %s\n", result.RunID)
+	return nil
+}
+```
+
+## Producer Responsibilities
+
+- Use a stable bundle id for the logical producer output that should replace the same destination artifact, such as `weather.hourly.brentwood`.
+- Set `PipelineID` to the configured upload pipeline that should process the bundle.
+- Do not include per-run timestamps, random values, or job ids in the bundle id unless each run should be treated as a different source.
+- Use an idempotency key that changes for every distinct producer run, such as `<bundle-id>.<run-id>`.
+- Reuse the same idempotency key only when retrying the exact same producer run with the same source manifest.
+- Map each generated file to a clean slash-separated bundle path, such as `report.md` or `assets/chart.png`.
+- Include only regular files. Symlinks, directories as files, devices, FIFOs, and sockets are rejected.
+- Keep file contents stable after upload inputs are selected. Bundle digests are calculated from file bytes.
+- Treat upload success as admission only. `UploadFiles` and `UploadBundle` return after the server accepts and validates the upload, not after all destinations publish.
+
+Valid bundle paths are relative slash paths. They must not be empty, absolute, contain backslashes, contain `.` or `..` path segments, contain empty path segments, or use reserved basenames `manifest.json` or `.distributor.json`.
+
+## Idempotency And Status
+
+`pkg/upload` sends `Idempotency-Key` on every upload. If the caller omits one, the package generates a random key for that call and reuses it for in-process retries. That is enough for transient network retry within one process, but it does not give cross-process retry identity.
+
+For producer jobs that may retry after process restart, supply a key derived from the producer run, such as `<bundle-id>.<run-id>`. Reusing the same key with the same token, pipeline id, and normalized source manifest returns the original accepted run. Reusing the same key with different source content in that scope returns a conflict. Reusing one key across multiple distinct report generations prevents those generations from being treated as new uploads.
+
+`Status` polls `/runs/<run-id>` while the distributor server retains the in-memory status record. Status values are `accepted`, `queued`, `running`, `succeeded`, and `failed`. Completed records expire according to the server's `server.http.retention` setting, and server restart clears status and idempotency records.
+
+Optional status check:
+
+```go
+status, err := client.Status(ctx, result.RunID)
+if err != nil {
+	return err
+}
+if status.Status == "failed" {
+	return fmt.Errorf("distributor run failed: %s", status.Error)
+}
+```
+
+## References
+
+In the `distributor` source tree:
+
+- `docs/consumers/pkg-upload.md`: Go upload package workflow.
+- `docs/consumers/pkg-bundle.md`: Go bundle package workflow.
+- `docs/integrations/http-upload.md`: canonical HTTP upload wire contract.
+- `docs/integrations/source-bundle.md`: canonical source bundle file-format contract.

docs/integrations/distributor/pkg-bundle.md

@@ -0,0 +1,90 @@
+# `pkg/bundle`
+
+Audience: upstream Go producer developers and LLM coding agents using `distributor` source bundle helpers.
+
+Import path:
+
+```go
+import "gitea.maximumdirect.net/eric/distributor/pkg/bundle"
+```
+
+`pkg/bundle` builds, writes, parses, and validates local source bundles. Use it directly when a producer writes bundles for `distributor` to discover, or when a producer wants to assemble and validate a bundle before using another transport.
+
+The canonical source bundle file-format contract is [Source Bundle Contract](../integrations/source-bundle.md).
+
+## Preferred Complete-Bundle Workflow
+
+Use `WriteBundle` when producer-generated files live outside the final bundle root.
+
+```go
+manifest, err := bundle.WriteBundle(bundle.WriteBundleOptions{
+	Root: "/var/spool/distributor/weather/hourly-2026-06-07T15",
+	ID:   "weather.hourly.brentwood",
+	Files: []bundle.BundleFile{
+		{SourcePath: "/tmp/weather/report.md", Path: "report.md"},
+		{SourcePath: "/tmp/weather/summary.txt", Path: "summary.txt"},
+	},
+})
+if err != nil {
+	return err
+}
+_ = manifest
+```
+
+`WriteBundle` copies each source file into a staged bundle root, writes `manifest.json`, validates the staged bundle, and promotes it into place. Set `Overwrite: true` only when the producer intentionally replaces an existing bundle root.
+
+## Existing Bundle Root Workflow
+
+Use `BuildManifest` and `WriteManifest` when files are already staged under the final bundle root.
+
+```go
+root := "/var/spool/distributor/weather/hourly-2026-06-07T15"
+manifest, err := bundle.BuildManifest(bundle.BuildOptions{
+	Root:  root,
+	ID:    "weather.hourly.brentwood",
+	Files: []string{"report.md", "summary.txt"},
+})
+if err != nil {
+	return err
+}
+if err := bundle.WriteManifest(root, manifest, bundle.WriteManifestOptions{}); err != nil {
+	return err
+}
+if err := bundle.ValidateBundle(root, manifest); err != nil {
+	return err
+}
+```
+
+Use `Scan: true` instead of `Files` only when every valid regular file under the root should be included. Scan mode includes dotfiles, skips reserved metadata files, rejects symlinks, and sorts paths lexically.
+
+## Paths And Ordering
+
+Bundle paths are slash-separated paths relative to the bundle root.
+
+Invalid paths include:
+
+- empty paths;
+- absolute paths;
+- paths containing backslashes;
+- `.` or `..` path segments;
+- empty path segments;
+- any basename of `manifest.json` or `.distributor.json`.
+
+Explicit file lists preserve caller order. File order is part of the bundle digest, so producers should choose it deliberately and keep it stable.
+
+The manifest `ID` is the logical source identity used by `distributor` destination comparison. Keep it stable for runs that should replace the same managed destination artifact. If every run uses a different manifest `ID`, `distributor` treats those runs as different sources and may report a destination conflict instead of replacing older output.
+
+## Validation And Digest Helpers
+
+Use `ValidateBundle` before handing an existing local bundle to another process. It verifies manifest semantics, file existence, regular-file type, file size, per-file SHA-256 digests, and bundle digest.
+
+Useful helpers:
+
+- `LoadManifest`: read `manifest.json` from a bundle root.
+- `ParseManifest` and `MarshalManifest`: parse or write manifest bytes.
+- `ValidateManifest`: validate manifest-only semantics.
+- `FileDigest`, `BundleDigest`, and `ValidateDigest`: digest helpers for diagnostics and tests.
+
+## Boundaries
+
+`pkg/bundle` does not upload bundles, publish destinations, transform Markdown, select pipelines, configure credentials, or write destination state. Those concerns belong to `pkg/upload` or the `distributor` application.

docs/integrations/distributor/pkg-upload.md

@@ -0,0 +1,122 @@
+# `pkg/upload`
+
+Audience: upstream Go producer developers and LLM coding agents submitting bundles to `distributor serve`.
+
+Import path:
+
+```go
+import "gitea.maximumdirect.net/eric/distributor/pkg/upload"
+```
+
+`pkg/upload` is the producer-facing HTTP upload client. It builds on `pkg/bundle`, packages valid source bundles as gzip-compressed tar archives, sends bearer authentication, routes uploads to a configured pipeline, includes idempotency keys, and exposes a status polling helper.
+
+`UploadFiles` examples also use:
+
+```go
+import "gitea.maximumdirect.net/eric/distributor/pkg/bundle"
+```
+
+The canonical HTTP wire contract is [HTTP Upload API Contract](../integrations/http-upload.md).
+
+## Client Construction
+
+```go
+client, err := upload.NewClient(upload.ClientOptions{
+	Endpoint: "https://distributor.example.com",
+	Token:    token,
+})
+if err != nil {
+	return err
+}
+```
+
+`Endpoint` is the distributor server base URL. The client derives `/v1/pipelines/<pipeline-id>/upload` and `/runs/<run-id>`. `Token` is required and is sent as `Authorization: Bearer <token>`. Token values are redacted from client errors.
+
+`HTTPClient` and `Retry` are optional. Defaults use a 30 second HTTP timeout and safe retry settings.
+
+## Upload Producer Files
+
+Use `UploadFiles` when the producer has generated output files but has not assembled a bundle directory.
+
+```go
+result, err := client.UploadFiles(ctx, upload.UploadFilesOptions{
+	PipelineID:     "weather-hourly",
+	ID:             "weather.hourly.brentwood",
+	IdempotencyKey: "weather.hourly.brentwood.20260607T150000Z",
+	Files: []bundle.BundleFile{
+		{SourcePath: "/tmp/weather/report.md", Path: "report.md"},
+		{SourcePath: "/tmp/weather/summary.txt", Path: "summary.txt"},
+	},
+})
+if err != nil {
+	return err
+}
+_ = result.RunID
+```
+
+`PipelineID` is required and selects the configured distributor workflow for this upload. `ID` is the source manifest id and identifies the logical artifact inside that workflow. `UploadFiles` creates a temporary bundle, writes and validates a manifest, uploads the archive, and removes temporary files when the call returns. It does not write into producer source directories.
+
+## Upload An Existing Bundle
+
+Use `UploadBundle` when the producer already has a complete local bundle root containing `manifest.json`.
+
+```go
+result, err := client.UploadBundle(ctx, upload.UploadBundleOptions{
+	PipelineID:     "weather-hourly",
+	Root:           "/var/spool/weather/hourly-2026-06-07T15",
+	IdempotencyKey: "weather.hourly.brentwood.20260607T150000Z",
+})
+if err != nil {
+	return err
+}
+_ = result.RunID
+```
+
+`PipelineID` is required for existing bundles too. `UploadBundle` validates the local bundle by default and uploads only `manifest.json` plus manifest-listed files. Unlisted files are not uploaded.
+
+## Result And Status
+
+Upload success means the server returned `202 Accepted` after staging and validating the upload. It does not mean all configured destinations have published.
+
+Poll status while the server retains the in-memory run record:
+
+```go
+status, err := client.Status(ctx, result.RunID)
+if err != nil {
+	return err
+}
+if status.Status == "failed" {
+	return fmt.Errorf("distributor run failed: %s", status.Error)
+}
+```
+
+Status values are `accepted`, `queued`, `running`, `succeeded`, and `failed`. Completed records expire according to `server.http.retention`; server restart clears run status and idempotency records.
+
+## Idempotency And Retry
+
+Every upload request includes `Idempotency-Key`.
+
+If `IdempotencyKey` is omitted, the client generates a random 128-bit lowercase hexadecimal key for that upload operation and reuses it for retries within the same call. For cross-process retry safety, producers should pass a key derived from the producer run, such as `<bundle-id>.<run-id>`.
+
+Do not reuse the same idempotency key for multiple distinct report generations. Reuse it only when retrying the exact same run with the same token, pipeline id, and source manifest. A repeated key with the same manifest in that scope returns the original accepted run instead of enqueueing another run; a repeated key with different content returns an idempotency conflict.
+
+The client retries only safe cases:
+
+- `503 Service Unavailable`;
+- temporary network errors;
+- ambiguous mid-upload failures.
+
+It does not retry after `202 Accepted` and does not retry `400`, `401`, `403`, `404`, `409`, `413`, or `415`.
+
+Detect conflicting key reuse with `errors.As`:
+
+```go
+var conflict *upload.IdempotencyConflictError
+if errors.As(err, &conflict) {
+	return fmt.Errorf("idempotency key was reused for different bundle content: %w", err)
+}
+```
+
+## Boundaries
+
+`pkg/upload` does not configure server pipelines, choose destinations, wait for publication completion automatically, persist client queues, provide durable idempotency across server restarts, or expose destination state. It submits complete source bundles to the configured HTTP upload API.

docs/integrations/scriptorium.md

@@ -1,34 +1,17 @@
-# weatherreporter Subprocess Integration
+# Scriptorium Integration
+
+This document describes the external Scriptorium CLI contract used by
+`weatherreporter`.
 
 ## Purpose
 
-This document defines the supported subprocess contract for weatherreporter invoking Scriptorium through the public CLI.
+`weatherreporter` invokes Scriptorium as a subprocess to preflight prompt input
+and generate Markdown reports. This page documents the CLI surface the adapter
+uses, not the full Scriptorium product.
 
-This is a CLI contract, not an internal Go package integration.
+## Commands Used
 
-## Supported Commands
-
-weatherreporter should invoke:
-
-- `scriptorium run`
-- `scriptorium render`
-
-Use `run` for generation.
-
-Use `render` for preflight/debug output without LLM execution.
-
-## Recommended Invocation Shapes
-
-Run:
-
-```bash
-scriptorium run \
-  --prompt <prompt_id> \
-  --input data_package=<path> \
-  --out <artifact_path>
-```
-
-Render:
+Render preflight:
 
 ```bash
 scriptorium render \
@@ -37,78 +20,79 @@ scriptorium render \
   --format json
 ```
 
-weatherreporter may add:
+Report generation:
 
-- `--config <path>`
-- `--profile <profile_id>`
-- repeatable `--input name=path`
-- repeatable `--var name=value`
-- runtime overrides when explicitly needed (`--model`, `--llm-base-url`, `--timeout`, etc.)
+```bash
+scriptorium run \
+  --prompt <prompt_id> \
+  --input data_package=<path> \
+  --out <artifact_path>
+```
 
-## Config And Directory Behavior
+`weatherreporter` always passes prompt input as
+`--input data_package=<path>`. The data package is structured YAML created by
+`internal/promptinput`; module snapshots remain separate JSON artifacts for
+inspection and Recent Changes.
 
-weatherreporter can rely on resolved app config or pass explicit paths.
+## Configured Arguments
 
-- default config search order:
-  1. `/usr/local/etc/scriptorium/config.yml`
-  2. `/etc/scriptorium/config.yml`
-- explicit `--config` requires file existence and valid syntax
-- CLI flags override config values
+The adapter can prepend configured flags before prompt-specific arguments:
 
-## Profile Selection
+- `--config <path>` from `scriptorium.config_path`
+- `--profile <profile>` from `scriptorium.profile`
 
-Profile selection follows runner behavior:
+It appends `scriptorium.extra_args` after the built-in arguments. Extra
+arguments are passed directly as argv items.
 
-1. explicit `--profile`
-2. prompt `default_profile`
-3. error if neither is available
+`scriptorium.binary` selects the executable name or path. If unset inside the
+adapter, it falls back to `scriptorium`.
 
-weatherreporter should treat prompt/profile IDs as deployment configuration, not hardcoded logic.
+## Execution Behavior
 
-## Input And Variable Contract
+The adapter runs Scriptorium without shell interpolation. Arguments are passed
+through `exec.CommandContext`.
 
-- Inputs use repeated `--input name=path`.
-- Input names must match prompt definition input names.
-- Variables use repeated `--var name=value` for small metadata values.
-- Prefer file inputs for large content.
+`scriptorium.timeout` limits each subprocess call when configured. Context
+cancellation or timeout returns an execution error.
 
-## Environment Contract
+Stdout and stderr are captured separately. Each stream is capped at 1 MiB and
+the result records whether truncation occurred.
 
-- Pass through required API-key environment variables referenced by `api_key_env`.
-- Never pass raw API keys via CLI arguments.
-- Keep subprocess environment scoped to required variables.
+## Results
 
-## Output And Error Handling
+Render results include:
 
-`run`:
+- full argv recorded as `command`
+- stdout
+- stderr
+- exit code
+- truncation flags when applicable
 
-- stdout: artifact body unless `--out` is used
-- `--out`: writes artifact to file
-- stderr: success summary and errors
+Run results include the same fields plus the requested output path.
 
-`render`:
+`weatherreporter` persists render preflight JSON when orchestration reaches the
+preflight save point. The final Markdown artifact is written by Scriptorium to
+the `--out` path.
 
-- stdout: prepared-run output unless `--out` is used
-- stderr: errors
+## Failure Behavior
 
-weatherreporter should capture stdout and stderr separately.
+The adapter validates required request fields before starting Scriptorium:
 
-## Exit Status Contract
+- prompt ID
+- data package path
+- output path for `run`
 
-- `0`: success
-- `1`: parse/config/load/render/generation/IO/runtime error
-- `2`: run completed but validation failed
+Nonzero exits return both the captured result and an error containing the exit
+code and stderr. A `run` exit code such as `2` is still treated as an error by
+the adapter, even if Scriptorium wrote output to the requested artifact path.
 
-A `run` exit code `2` can still produce output (stdout or `--out`).
+Subprocess start failures, context cancellation, and timeouts return errors
+without fabricating a successful result.
 
 ## Security Notes
 
-- Treat generated artifacts and stderr logs as potentially sensitive.
-- Avoid logging full rendered prompts by default in production contexts.
-- Use controlled output paths and access controls for persisted artifacts.
-
-## Canonical References
-
-- CLI behavior: [CLI reference](https://gitea.maximumdirect.net/eric/scriptorium/docs/cli.md)
-- Config behavior: [Configuration reference](https://gitea.maximumdirect.net/eric/scriptorium/docs/config.md)
-- Operations and failure handling: [Operations guide](https://gitea.maximumdirect.net/eric/scriptorium/docs/operations.md), [Troubleshooting](https://gitea.maximumdirect.net/eric/scriptorium/docs/troubleshooting.md)
+- The adapter does not invoke a shell.
+- Generated artifacts, rendered prompt context, stdout, and stderr can contain
+  operationally sensitive data.
+- API keys should be provided through the Scriptorium environment or
+  Scriptorium configuration, not through `weatherreporter` CLI arguments.

docs/integrations/weatherapi.md

@@ -1,354 +1,132 @@
-# weatherapi External API
+# Weather API Integration
 
-This document describes the public HTTP API exposed by `weatherapi` for external consumers.
+This document describes the external Weather API contract used by
+`weatherreporter`.
+
+## Purpose
+
+`weatherreporter` uses a configured Weather API base URL to fetch normalized
+weather source data and assemble a `weatherdata.Bundle`. This is an integration
+contract for the project adapter, not a complete public API reference for the
+upstream service.
 
 ## Base URL
 
-The service is typically served at your deployment host, for example:
+`weather_api.base_url` must be an absolute URL. Adapter requests join this base
+URL with the endpoint paths listed below. Generation and explicit bundle fetches
+fail before any HTTP request when the base URL is empty or not absolute.
 
-- `https://weather.api.rakestrawhome.com`
+The HTTP client uses `weather_api.timeout`.
 
-All paths below are relative to the service root.
+## Response Envelope
 
-## Common Conventions
-
-### Response envelope
-
-All endpoints return a top-level envelope:
-
-- `data`: endpoint payload or `null` when no current/latest resource is available.
-
-JSON example:
+Every response used by the adapter must be JSON with a top-level `data` field:
 
 ```json
 {
-  "data": {"...": "..."}
+  "data": {}
 }
 ```
 
-### Output format
+For most sources, `data: null` is treated as a missing source. Missing optional
+sources follow the configured missing-source policy. Missing hourly forecast
+data fails bundle fetching because hourly periods are required for report
+generation.
 
-Supported via `format` query parameter (case-insensitive):
+`/alerts/active` is the exception: a successful response with `data: null`
+means the endpoint was checked and there are no current active alerts. The
+adapter records a non-missing alerts source and an empty alert run.
 
-- `json` (default)
-- `xml`
-- `text`
+Malformed JSON envelopes, non-2xx statuses, and response read failures include
+endpoint context in returned errors. Decode errors include source context when
+they fail the fetch; optional malformed sources follow the missing-source policy.
 
-### Units
+## Query Parameters
 
-Supported via `units` query parameter (case-insensitive):
+The adapter sends these query parameters:
 
-- `metric` (default)
-- `us`
+- `format`: from `weather_api.format`; configuration validation requires `json`
+- `units`: from `weather_api.units`
+- `precision`: from `weather_api.precision` on observations, current
+  conditions, hourly forecast, and narrative forecast requests
+- `tz`: from `weather_api.timezone` on hourly forecast, narrative forecast, and
+  discussion requests
 
-Endpoints that include unit-based numeric fields return either metric or US field variants depending on this value.
+Alerts do not receive `precision` or `tz`. Weather story requests receive only
+`format=json`.
 
-### Precision
+## Endpoints Used
 
-Supported where documented via `precision` query parameter:
+The adapter fetches these endpoints once per bundle:
 
-- integer range: `0` to `2`
-- controls decimal rounding of numeric output fields
+- `/observations`
+- `/conditions/current`
+- `/forecast/hourly`
+- `/forecast/narrative`
+- `/alerts/active`
+- `/discussion`
+- `/weatherstories/latest`
 
-### Timezone (`tz` / `TZ`)
+`weatherreporter` does not call day-slice forecast endpoints or discussion
+subsection endpoints. Report-period selection and daypart summarization happen
+inside Go after the full hourly and narrative products are fetched.
 
-Supported where documented:
+## Required And Optional Sources
 
-- accepted values include:
-  - IANA timezone names (example: `America/Chicago`)
-  - common US abbreviations (example: `CDT`, `EST`)
-  - UTC offsets in `±H`, `±HH`, or `±HH:MM` (example: `-5`, `+09:30`)
-  - aliases including `Chicago` and `Stl`
-- `tz` and `TZ` are treated equivalently
-- if both are provided, they must match exactly or the request fails
+Hourly forecast is required:
 
-Timezone affects datetime rendering and day-slice filtering for `/today` and `/tomorrow` forecast routes.
+- `data: null` for `/forecast/hourly` fails the fetch.
+- an hourly forecast with no `periods` fails the fetch.
+- malformed hourly data fails the fetch.
 
-### Query validation
+Other fetched sources are optional and follow `missing_source.default` or a
+source-specific `missing_source.sources` policy:
 
-- Unknown query parameters are rejected with `400 Bad Request`.
-- Invalid parameter values are rejected with `400 Bad Request`.
+- `observations` for `/observations`
+- `current` for `/conditions/current`
+- `narrative` for `/forecast/narrative`
+- `alerts` for `/alerts/active`
+- `discussion` for `/discussion`
+- `weather_story` for `/weatherstories/latest`
 
-Error response body follows the service error envelope; exact fields may vary by error type.
+Policy behavior:
 
-## Endpoints
+- `error`: fail the fetch for that source
+- `warn`: omit the source data, add a warning, and continue
+- `none`: omit the source data and continue without a warning
 
-## `GET /observations`
+For `/alerts/active`, an HTTP error or missing `data` field still fails or
+follows the relevant error path, but explicit `data: null` is not a
+missing-source condition.
 
-Returns the latest weather observation.
+## Source Identity
 
-Query parameters:
+For source payloads accepted into the bundle, including the explicit `null`
+alerts payload, the adapter records:
 
-- `units`: `metric` | `us`
-- `format`: `json` | `xml` | `text`
-- `precision`: `0..2`
+- source name
+- endpoint path
+- query parameters sent
+- fetch time
+- source issue and update timestamps when present in the payload
+- SHA-256 hash of the compact raw `data` JSON
 
-Response `data` fields:
+Warnings are recorded both on the affected source and on the bundle-level
+warnings list.
 
-- `stationId` (string, optional)
-- `stationName` (string, optional)
-- `timestamp` (RFC3339 datetime, required)
-- `conditionCode` (integer WMO code, required)
-- `isDay` (boolean, optional)
-- `textDescription` (string, optional)
-- Metric mode fields:
-  - `temperatureC`, `dewpointC`, `windSpeedKmh`, `windGustKmh`, `barometricPressurePa`, `visibilityMeters`, `relativeHumidityPercent`, `apparentTemperatureC` (number, optional)
-  - `windDirectionDegrees` (number, optional)
-- US mode fields:
-  - `temperatureF`, `dewpointF`, `windSpeedMph`, `windGustMph`, `barometricPressureInHg`, `visibilityMiles`, `relativeHumidityPercent`, `apparentTemperatureF` (number, optional)
-  - `windDirectionDegrees` (number, optional)
-- `presentWeather` (array, optional)
+## Compatibility Assumptions
 
-## `GET /alerts/active`
+The adapter expects payload fields compatible with the internal forecast bundle
+types in `internal/forecast/bundle.go`, including:
 
-Returns the latest active alert run.
+- observation timestamps and observation values
+- current condition values
+- forecast run metadata and `periods`
+- active alert run data
+- discussion metadata, key messages, and short/long-term section text
+- latest weather story title, description, timing, priority, order, alt text,
+  and download URL
 
-Query parameters:
-
-- `units`: `metric` | `us` (accepted; does not materially alter alert payload)
-- `format`: `json` | `xml` | `text`
-
-Response `data` fields:
-
-- Weather alert run object from canonical model (includes run metadata and active alerts list).
-
-## `GET /conditions/current`
-
-Returns current conditions synthesized from latest observation/forecast data.
-
-Query parameters:
-
-- `units`: `metric` | `us`
-- `format`: `json` | `xml` | `text`
-- `precision`: `0..2`
-
-Response `data` fields:
-
-- Common:
-  - `conditionText` (string, optional)
-  - `isDay` (boolean, optional)
-  - `relativeHumidityPercent` (number, optional)
-  - `windDirectionDegrees` (number, optional)
-- Metric mode:
-  - `temperatureC`, `apparentTemperatureC`, `dewpointC`, `windSpeedKmh` (number, optional)
-- US mode:
-  - `temperatureF`, `apparentTemperatureF`, `dewpointF`, `windSpeedMph` (number, optional)
-
-## Forecast endpoints
-
-- `GET /forecast/hourly`
-- `GET /forecast/hourly/today`
-- `GET /forecast/hourly/tomorrow`
-- `GET /forecast/narrative`
-- `GET /forecast/narrative/today`
-- `GET /forecast/narrative/tomorrow`
-
-Query parameters:
-
-- `units`: `metric` | `us`
-- `format`: `json` | `xml` | `text`
-- `precision`: `0..2`
-- `tz` or `TZ`: timezone selector
-
-Day-slice routes:
-
-- `/today` returns periods with `period.startTime` in the current calendar day for the resolved timezone.
-- `/tomorrow` returns periods with `period.startTime` in the next calendar day for the resolved timezone.
-
-Response `data` fields:
-
-- Run-level:
-  - `locationId` (string, optional)
-  - `locationName` (string, optional)
-  - `issuedAt` (RFC3339 datetime, required)
-  - `updatedAt` (RFC3339 datetime, optional)
-  - `product` (string, required; e.g. `hourly`, `narrative`)
-  - `latitude`, `longitude` (number, optional)
-  - Metric mode: `elevationMeters` (number, optional)
-  - US mode: `elevationFeet` (number, optional)
-  - `periods` (array, required)
-- Period fields:
-  - `startTime`, `endTime` (RFC3339 datetime, required)
-  - `name` (string, optional)
-  - `isDay` (boolean, optional)
-  - `conditionCode` (integer WMO code, optional)
-  - `textDescription` (string, optional)
-  - Metric mode (optional):
-    - `temperatureC`, `temperatureCMin`, `temperatureCMax`, `dewpointC`, `windSpeedKmh`, `windGustKmh`, `barometricPressurePa`, `visibilityMeters`, `apparentTemperatureC`, `cloudCoverPercent`, `probabilityOfPrecipitationPercent`, `precipitationAmountMm`, `snowfallDepthMM`, `uvIndex`, `relativeHumidityPercent`, `windDirectionDegrees`
-  - US mode (optional):
-    - `temperatureF`, `temperatureFMin`, `temperatureFMax`, `dewpointF`, `windSpeedMph`, `windGustMph`, `barometricPressureInHg`, `visibilityMiles`, `apparentTemperatureF`, `cloudCoverPercent`, `probabilityOfPrecipitationPercent`, `precipitationAmountIn`, `snowfallDepthIn`, `uvIndex`, `relativeHumidityPercent`, `windDirectionDegrees`
-
-Notes:
-
-- Narrative periods may omit `conditionCode`.
-- Text format uses forecast-specific templates (`hourly` and `narrative`).
-
-## Discussion endpoints
-
-- `GET /discussion`
-- `GET /discussion/key-messages`
-- `GET /discussion/short-term`
-- `GET /discussion/long-term`
-
-Query parameters:
-
-- `units`: `metric` | `us` (accepted; does not materially alter discussion payload)
-- `format`: `json` | `xml` | `text`
-- `tz` or `TZ`: timezone selector
-
-Response `data` fields:
-
-- `/discussion`:
-  - `officeId` (string, optional)
-  - `officeName` (string, optional)
-  - `product` (string, required)
-  - `issuedAt` (RFC3339 datetime, required)
-  - `updatedAt` (RFC3339 datetime, optional)
-  - `keyMessages` (array of string)
-  - `shortTerm` (object, optional)
-  - `longTerm` (object, optional)
-- `/discussion/key-messages`:
-  - `officeId`, `officeName`, `product`, `issuedAt`, `updatedAt`
-  - `keyMessages` (array of string)
-- `/discussion/short-term`:
-  - `officeId`, `officeName`, `product`, `issuedAt`, `updatedAt`
-  - `shortTerm` (object, optional)
-- `/discussion/long-term`:
-  - `officeId`, `officeName`, `product`, `issuedAt`, `updatedAt`
-  - `longTerm` (object, optional)
-
-Discussion section object fields:
-
-- `title` (string, optional)
-- `narrative` (string, optional)
-- `issuedAt` (RFC3339 datetime, optional)
-
-## Examples
-
-### Observation (JSON, metric)
-
-```http
-GET /observations?format=json&units=metric&precision=1
-```
-
-```json
-{
-  "data": {
-    "stationId": "KSTL",
-    "timestamp": "2026-05-29T14:00:00Z",
-    "conditionCode": 3,
-    "isDay": true,
-    "textDescription": "Partly cloudy",
-    "temperatureC": 24.4,
-    "windSpeedKmh": 17.2,
-    "relativeHumidityPercent": 56.0
-  }
-}
-```
-
-### Alerts (JSON)
-
-```http
-GET /alerts/active?format=json
-```
-
-```json
-{
-  "data": {
-    "asOf": "2026-05-29T14:00:00Z",
-    "alerts": []
-  }
-}
-```
-
-### Current conditions (JSON, US)
-
-```http
-GET /conditions/current?format=json&units=us&precision=1
-```
-
-```json
-{
-  "data": {
-    "conditionText": "Partly cloudy",
-    "isDay": true,
-    "temperatureF": 75.9,
-    "apparentTemperatureF": 76.1,
-    "windSpeedMph": 10.7,
-    "relativeHumidityPercent": 56.0
-  }
-}
-```
-
-### Forecast narrative (JSON, optional `conditionCode`)
-
-```http
-GET /forecast/narrative?format=json&units=metric&precision=1&tz=America/Chicago
-```
-
-```json
-{
-  "data": {
-    "locationId": "nws-lsx-grid-90-74",
-    "issuedAt": "2026-05-29T10:30:00-05:00",
-    "product": "narrative",
-    "periods": [
-      {
-        "startTime": "2026-05-29T13:00:00-05:00",
-        "endTime": "2026-05-29T19:00:00-05:00",
-        "name": "Today",
-        "isDay": true,
-        "textDescription": "Partly sunny, with a high near 81.",
-        "temperatureC": 27.2,
-        "windSpeedKmh": 18.0,
-        "probabilityOfPrecipitationPercent": 10.0
-      }
-    ]
-  }
-}
-```
-
-### Forecast hourly today (text)
-
-```http
-GET /forecast/hourly/today?format=text&units=us&precision=1&tz=CDT
-```
-
-```text
-<plain text forecast output>
-```
-
-### Discussion key messages (JSON)
-
-```http
-GET /discussion/key-messages?format=json&tz=Chicago
-```
-
-```json
-{
-  "data": {
-    "officeId": "LSX",
-    "product": "discussion",
-    "issuedAt": "2026-05-29T09:25:00-05:00",
-    "keyMessages": [
-      "Scattered showers possible this evening.",
-      "Warmer temperatures this weekend."
-    ]
-  }
-}
-```
-
-### Invalid timezone error example
-
-```http
-GET /forecast/narrative?tz=not-a-timezone
-```
-
-```json
-{
-  "error": {
-    "code": "invalid_parameter",
-    "message": "tz must be a valid timezone"
-  }
-}
-```
+The adapter intentionally keeps upstream transport and envelope details inside
+`internal/adapters/weatherapi`; downstream packages consume the normalized
+bundle.

docs/internal/app-orchestration.md

@@ -0,0 +1,148 @@
+# App Orchestration Internals
+
+This document describes the workflow coordinator in `internal/app`.
+
+## Purpose
+
+`internal/app` coordinates the top-level use cases after CLI parsing and config
+loading are complete. It resolves report definitions, fetches weather data,
+builds collected and derived facts, builds module snapshots and prompt-input
+artifacts, invokes Scriptorium through the adapter boundary, optionally
+notifies distributor through an app-owned notifier boundary, persists managed
+state, runs batches, and reads existing artifacts for inspection.
+
+## Inputs And Outputs
+
+Inputs:
+
+- `GenerateRequest` for one report command
+- `BatchRequest` for morning or evening batch commands
+- `FetchBundleRequest` for explicit bundle fetch and save workflows
+- `ReportRequest` for single-report generation
+- resolved report definitions from `internal/report`
+- weather data bundles from `internal/adapters/weatherapi`
+- prior snapshots loaded from `internal/state`
+- optional renderer, notifier, and state-store fakes for tests
+
+Outputs:
+
+- generated report results with JSON module snapshot, YAML data package,
+  preflight, report, metadata, prior snapshot, Recent Changes, Scriptorium
+  result details, and notification result when attempted
+- batch summaries with per-report status, artifact paths, error text, and
+  notification outcome when attempted
+- saved Weather API bundle JSON for fetch workflows
+- inspection JSON values for reports, metadata, module snapshots, data
+  packages, prior snapshots, and source provenance
+
+## Boundaries
+
+`internal/app` owns workflow order and request composition. It does not parse
+CLI flags, load YAML files directly, implement HTTP transport, own fact
+derivation algorithms, define report periods, compare rendered Markdown, or
+construct Scriptorium argv.
+
+Report selection and report identity policy come from `internal/report`.
+Collected and derived fact contracts come from `internal/facts`.
+Weather API transport stays in `internal/adapters/weatherapi`. Scriptorium
+subprocess behavior stays in `internal/adapters/scriptorium`. Distributor
+upload behavior stays in `internal/adapters/distributor`. Filesystem layout and
+persisted metadata stay in `internal/state`.
+
+## Config Fields Used
+
+- `weather_api.*` for Weather API client construction and module metadata
+- `scriptorium.*` for renderer construction
+- `workspace.*` for filesystem state
+- `dayparts` for daily and outlook summarization
+- `recent_change.*` for structured Recent Changes thresholds
+- `notify.distributor.*` for optional notification after report generation
+
+Output copy flags are command request fields. They are not configuration
+defaults.
+
+## Generation Workflow
+
+Single-report generation follows this order:
+
+1. Resolve the command report to a `report.Resolved` value.
+2. Create or use a filesystem store.
+3. Locate any prior compatible snapshot through `internal/state`.
+4. Fetch a Weather API bundle.
+5. Build collected and derived facts once.
+6. Execute configured modules and save the module snapshot.
+7. Compute Recent Changes from structured prior and current module snapshots.
+8. Build and save the YAML Scriptorium `data_package`.
+9. Run Scriptorium render preflight.
+10. Save preflight JSON when a render result is available.
+11. Save metadata for inspection.
+12. Run Scriptorium report generation to the managed report path.
+13. Copy the managed report to the requested `--out` path when provided.
+14. Save metadata with the managed report path.
+15. If distributor notification is enabled, notify using the managed report
+    path as the source file.
+16. Save a distributor notification debug artifact and update metadata with its
+    path.
+
+If render preflight returns both a result and an error, preflight JSON and
+metadata are persisted before the error is returned. If Scriptorium report
+generation returns an error after writing output, the managed report and
+metadata remain inspectable. Notification is not attempted after Weather API,
+module snapshot, prompt input, render, Scriptorium run, or metadata-save
+failures.
+When notification is attempted, the debug artifact records request identity,
+including rendered pipeline ID, bundle paths, accepted upload fields,
+distributor status fields, raw status report JSON when available, and redacted
+failure context.
+`--out` copies are never used as notification source files.
+
+## Batch Workflow
+
+`run morning` resolves Daily Today, 3-Day Outlook, and Weekend Outlook except
+on Sunday. `run evening` resolves Daily Tomorrow. Batch output copy names come
+from report definitions. Batch generation continues independent reports after a
+failure, records each result, writes compact status lines to stderr, emits a
+JSON summary to stdout, and returns an aggregate error when any report failed.
+When notification is enabled, each successfully generated report is notified
+independently. Notification failure marks that report failed, records
+notification fields in the batch result, and does not stop later reports.
+`--out-dir` copies are never used as notification source files.
+
+## Inspection Workflow
+
+Inspection workflows load existing filesystem state only. They do not fetch
+weather data or invoke Scriptorium. Run-specific inspect commands share the same
+store and metadata lookup path, then load the requested artifact or derived
+inspection view.
+
+## Failure Behavior
+
+- Resolve errors stop the requested workflow before fetching weather data.
+- Weather API and module execution errors stop that report before Scriptorium
+  runs.
+- Prompt input validation fails before render preflight.
+- Render and run errors preserve Scriptorium stderr and exit-code context.
+- Notification errors are wrapped with report ID, RunID, and managed report path
+  context and are recorded separately in batch results.
+- Metadata and artifact path errors include filesystem context.
+- Batch failures are recorded per report and surfaced through an aggregate
+  batch error.
+
+## Tests
+
+Inspect:
+
+- `internal/app/app_test.go`
+- `internal/cli/root_test.go`
+- `internal/state/filesystem_test.go`
+
+## Invariants
+
+- Report behavior is resolved through `internal/report`.
+- Generated reports use the same app request and result types regardless of
+  report ID.
+- Render preflight precedes Scriptorium report generation.
+- Recent Changes are computed from structured module snapshots.
+- Metadata links artifacts produced for a run.
+- Distributor notification maps the managed Markdown report path to configured
+  bundle paths; extra output copies are not upload sources.

docs/internal/briefing.md

@@ -0,0 +1,104 @@
+# Module Builder Internals
+
+This document describes module builder behavior in `internal/briefing`.
+
+## Purpose
+
+`internal/briefing` turns report metadata, collected weather data, and derived
+forecast facts into prompt-facing module outputs. The package also owns the
+module registry used to validate report composition and config overrides.
+
+Module outputs are structured prompt inputs. They are not rendered report prose
+and they are not persisted by this package.
+
+## Inputs And Outputs
+
+Inputs:
+
+- resolved report definition, generation time, timezone, and valid period
+- collected facts built from `weatherdata.Bundle`
+- derived daily, daypart, precipitation, alert, and storm-window facts where
+  required
+- configured units, timezone, and descriptive location context
+- typed module options from report defaults or config overrides
+
+Outputs:
+
+- `ModuleDefinition` values with module ID, stanza name, option type,
+  supported reports, fact requirements, missing-data behavior, and builder
+- `module.Output` values for source-oriented stanzas:
+  `metadata`, `current_conditions`, `narrative_forecast`, `hourly_forecast`,
+  `alert_digest`, `area_forecast_discussion`, and `weather_story`
+- `module.Output` values for derived stanzas:
+  `derived_daily_summary`, `derived_daypart_summaries`, `precip_timing`,
+  `outdoor_windows`, and `tomorrow_planning`
+
+Every registered composition entry has a builder. Unknown or unimplemented
+module IDs fail validation instead of being skipped.
+
+Prompt-facing module values use local, human-readable date and time labels
+where the LLM is expected to reason about report content. Canonical timestamps
+remain in report metadata, source provenance, and integration artifacts.
+
+## Boundaries
+
+- This package selects and shapes already-collected weather facts for prompts.
+- It validates module composition against report compatibility and option
+  types.
+- It does not fetch weather data, compare prior snapshots, write module
+  snapshots, build YAML data packages, invoke Scriptorium, or write workflow
+  metadata.
+
+## Config Fields Used
+
+The app layer passes effective units, timezone, and location context into the
+module context. `internal/facts` consumes daypart configuration before module
+builders run. Configured `location` values are prompt context only; Weather API
+`sourceLocationId` and `sourceLocation` remain source provenance.
+
+`area_forecast_discussion` uses optional `sections` configuration to include a
+subset of discussion fields.
+
+## External Adapters Used
+
+None directly.
+
+## State Or Manifest Behavior
+
+None. `internal/app` collects module outputs into a `module.Snapshot`, and
+`internal/state` persists that snapshot.
+
+## Skip And Resume Behavior
+
+None. Builders either emit a module output, omit optional unavailable data, or
+return an error for invalid required inputs.
+
+## Failure Behavior
+
+- Required derived modules return errors when their dependent facts are not
+  available.
+- Module registry construction rejects duplicate module IDs and duplicate
+  stanza names.
+- Composition validation rejects unknown modules, duplicate modules,
+  incompatible report/module combinations, duplicate stanza names, and invalid
+  option shapes.
+- Source-oriented module builders omit missing optional current conditions,
+  forecast discussion, and weather story stanzas.
+- Alert digest output distinguishes checked empty alert data from missing alert
+  source data.
+
+## Tests
+
+Inspect:
+
+- `internal/briefing/base_modules_test.go`
+- `internal/briefing/derived_modules_test.go`
+- `internal/briefing/modules_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Module outputs contain structured weather facts and source context.
+- Common metadata includes RunID, report ID, prompt ID, valid period, source
+  provenance, source hashes, source warnings, and configured prompt location.
+- Prompt input packaging and Scriptorium execution remain outside this package.

docs/internal/changes.md

@@ -0,0 +1,75 @@
+# Changes Internals
+
+This document describes structured Recent Changes comparison.
+
+## Purpose
+
+`internal/changes` compares current and prior module snapshots and emits
+compact change records for prompt input data packages.
+
+## Inputs And Outputs
+
+Inputs:
+
+- prior module snapshot
+- current module snapshot
+- comparison thresholds from configuration
+
+Outputs:
+
+- ordered `changes.Change` items with type, message, previous value, and current
+  value where useful
+
+## Boundaries
+
+- This package compares structured module snapshot data only.
+- It does not read filesystem state, find prior snapshots, render Markdown,
+  invoke Scriptorium, or compare generated report text.
+
+## Config Fields Used
+
+The app maps these fields into comparison thresholds:
+
+- `recent_change.temperature_degrees`
+- `recent_change.precip_probability_points`
+- `recent_change.wind_gust_miles_per_hour`
+- `recent_change.precip_timing_shift_minutes`
+
+## External Adapters Used
+
+None.
+
+## State Or Manifest Behavior
+
+None directly. The app loads prior module snapshots through `internal/state`
+before calling comparison functions.
+
+## Skip And Resume Behavior
+
+No resume behavior. When the app has no prior comparable snapshot, it sends an
+empty Recent Changes list without calling a comparison function.
+
+## Failure Behavior
+
+- Daily comparison requires `derived_daily_summary` and
+  `derived_daypart_summaries` stanzas. It also uses `alert_digest` and
+  `precip_timing` when present.
+- 3-Day comparison requires `derived_daypart_summaries`.
+- Weekend comparison requires `derived_daypart_summaries`.
+- Storm Report comparison returns no changes.
+
+## Tests
+
+Inspect:
+
+- `internal/changes/daily_test.go`
+- `internal/changes/three_day_test.go`
+- `internal/changes/weekend_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Recent Changes are based on structured snapshots, not Markdown report text.
+- Report compatibility is determined outside this package by report definitions
+  and state lookup.
+- Output stays compact enough for prompt input.

docs/internal/distributor-adapter.md

@@ -0,0 +1,123 @@
+# Distributor Adapter Internals
+
+This document describes the distributor upload adapter in
+`internal/adapters/distributor`.
+
+## Purpose
+
+The adapter submits generated weatherreporter Markdown reports to a configured
+distributor HTTP upload endpoint. It isolates distributor package types,
+token-env lookup, upload client construction, source-bundle file mapping,
+timeout handling, status polling, and upload error wrapping from app
+orchestration.
+
+## Inputs And Outputs
+
+Inputs:
+
+- distributor endpoint URL
+- token environment variable name
+- upload timeout
+- pipeline ID
+- bundle ID
+- idempotency key
+- source Markdown report path and bundle-relative path mappings
+- bundle created timestamp
+- context for cancellation
+
+Outputs:
+
+- accepted distributor run ID
+- accepted distributor upload status
+- distributor run status, status polling error, and raw run report JSON when available
+- weatherreporter-owned idempotency conflict error when applicable
+
+## Boundaries
+
+`internal/adapters/distributor` is the only weatherreporter package that imports
+`gitea.maximumdirect.net/eric/distributor/pkg/upload` or
+`gitea.maximumdirect.net/eric/distributor/pkg/bundle`.
+
+The app layer passes weatherreporter-owned request values to the adapter. The
+adapter does not choose report types, render templates, select output copies,
+configure destinations, wait for downstream publication, transform Markdown, or
+persist notification state.
+
+Full upstream distributor package and HTTP contract details stay under
+`docs/integrations/distributor/`.
+
+## Config Fields Used
+
+The adapter is built from `notify.distributor` config:
+
+- `endpoint`
+- `token_env`
+- `timeout`
+
+The app layer renders pipeline ID, bundle ID, idempotency key, and bundle paths
+from:
+
+- `pipeline_id_template`
+- `bundle_id_template`
+- `idempotency_key_template`
+- `report_path_templates`
+
+The token value is read from the environment variable named by `token_env`
+after config loading and `secrets.directory` processing.
+
+## Upload Behavior
+
+The adapter calls distributor `UploadFiles` with one or more file mappings:
+
+- pipeline ID: the rendered distributor workflow selector
+- source path: the managed Markdown report path selected by app orchestration
+- bundle paths: rendered bundle-relative report paths
+- created: the report generation timestamp
+
+The adapter creates a distributor upload client with the configured endpoint,
+bearer token, and timeout-backed HTTP client. It also wraps the upload context
+with the configured timeout when the timeout is greater than zero.
+
+After upload acceptance, the adapter polls distributor `Status` for the accepted
+run ID until the run reaches `succeeded` or `failed`, or until the configured
+timeout expires. It returns the latest status, error text, and raw report JSON in
+weatherreporter-owned types so app orchestration can persist them in the
+notification debug artifact. Status lookup failures or timeout before a terminal
+state are kept as debug status errors on an otherwise accepted upload. A
+terminal distributor run status of `failed` is returned as a notification failure
+with the status report preserved.
+
+## Failure Behavior
+
+The adapter validates required endpoint, token env name, token value, pipeline
+ID, bundle ID, idempotency key, upload files, source paths, bundle paths, and
+upload client inputs before uploading.
+
+Upload failures include endpoint, pipeline ID, bundle ID, idempotency key,
+source paths, and bundle paths context. Token values are redacted from adapter
+errors.
+
+Distributor idempotency conflicts are exposed as a weatherreporter-owned
+`IdempotencyConflictError`, so callers do not depend on upstream distributor
+types.
+
+## Tests
+
+Inspect:
+
+- `internal/adapters/distributor/client_test.go`
+- `internal/app/app_test.go`
+- `internal/cli/root_test.go`
+
+Adapter tests use a fake upload client factory and do not require a live
+distributor service.
+
+## Invariants
+
+- Distributor package types do not leak outside the adapter.
+- Only the managed Markdown report is uploaded.
+- The adapter never scans the workspace.
+- Token values are not included in errors, CLI output, metadata, docs, or
+  examples.
+- Destination routing and Markdown-to-HTML transformation belong to
+  distributor, not weatherreporter.

docs/internal/facts.md

@@ -0,0 +1,72 @@
+# Fact Contracts Internals
+
+This document describes the fact contract boundary.
+
+## Purpose
+
+`internal/facts` separates normalized upstream facts collected for a report run
+from conservative report-scoped facts derived from them. The package gives app
+orchestration one place to build reusable facts before module execution.
+
+## Inputs And Outputs
+
+Inputs:
+
+- `weatherdata.Bundle` from the Weather API adapter
+- resolved report definition and valid period
+- report timezone
+- configured daypart definitions
+
+Outputs:
+
+- `facts.CollectedFacts` with normalized source facts plus separate source
+  provenance and warnings
+- `facts.DerivedFacts` with valid-period forecast slices, alert overlaps,
+  daily summaries, daypart summaries, and Storm Report window summary
+
+## Boundaries
+
+- This package owns fact assembly and reusable deterministic derivation for a
+  report run.
+- It does not fetch upstream data, build prompt wording, compare prior
+  snapshots, write workflow state, invoke Scriptorium, or define modules.
+
+## Config Fields Used
+
+- `dayparts[].name`
+- `dayparts[].start`
+- `dayparts[].end`
+- `weather_api.timezone`
+
+## External Adapters Used
+
+None directly. Collected facts are built from `weatherdata.Bundle`.
+
+## State Or Manifest Behavior
+
+None. Source provenance and warnings remain data fields for downstream metadata
+and inspection.
+
+## Failure Behavior
+
+- Invalid or missing report valid periods return an error.
+- Invalid timezone names return an error.
+- Missing required hourly forecast data returns the underlying forecast
+  derivation error for reports that require daily summaries.
+- Missing optional narrative, alert, discussion, daily, or weather story data
+  produces empty or nil derived fields.
+
+## Tests
+
+Inspect:
+
+- `internal/facts/facts_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Collected facts are built once from a fetched bundle.
+- Derived facts are scoped to one resolved report.
+- Source provenance and warnings stay separate from ordinary fact fields.
+- Prompt-specific wording and one-off presentation decisions stay outside this
+  package.

docs/internal/forecast-derivation.md

@@ -0,0 +1,76 @@
+# Forecast Derivation Internals
+
+This document describes deterministic forecast summarization in
+`internal/forecast`.
+
+## Purpose
+
+`internal/forecast` converts normalized weather data into daily and period
+summaries used by fact builders and module builders.
+
+## Inputs And Outputs
+
+Inputs:
+
+- `weatherdata.Bundle`
+- local date or resolved report period
+- timezone
+- configured daypart definitions
+
+Outputs:
+
+- `forecast.DailySummary` for one local civil day
+- one clipped daily summary per local day or partial day from
+  `BuildPeriodDailySummaries`
+- daypart summaries with selected hourly periods, ranges, timed maximums,
+  conditions, indicators, and alert overlaps
+
+## Boundaries
+
+- This package groups, selects, and summarizes already-normalized forecast
+  data.
+- It does not perform HTTP calls, parse CLI flags, resolve report definitions,
+  compare prior snapshots, build prompt input packages, or invoke Scriptorium.
+
+## Config Fields Used
+
+- `dayparts[].name`
+- `dayparts[].start`
+- `dayparts[].end`
+
+Threshold constants for basic indicators live in forecast code rather than
+configuration.
+
+## External Adapters Used
+
+None directly. Forecast data arrives through `weatherdata.Bundle`.
+
+## State Or Manifest Behavior
+
+None. Source warnings and provenance from the bundle are carried into summaries
+for later metadata and module output.
+
+## Skip And Resume Behavior
+
+None. Missing optional source context can produce empty selections, but missing
+required hourly data fails summarization.
+
+## Failure Behavior
+
+- A nil bundle or missing hourly forecast data returns an error.
+- Invalid daypart definitions return parse errors with context.
+- Alert records without parseable RFC3339 timing are skipped.
+- Empty selected periods produce empty summaries rather than generated prose.
+
+## Tests
+
+Inspect:
+
+- `internal/forecast/derive_test.go`
+- `internal/timeutil/periods_test.go`
+
+## Invariants
+
+- Go owns report-period selection and meteorological summarization.
+- Weather facts come from normalized source data.
+- Outputs remain JSON-inspectable and independent of CLI, state, and adapters.

docs/internal/module.md

@@ -0,0 +1,98 @@
+# Module Contract Internals
+
+This document describes the module contract in `internal/module`.
+
+## Purpose
+
+`internal/module` defines the shared identifiers and data envelopes used for
+prompt-facing modules. Report definitions use module IDs for composition,
+module builders produce outputs with stanza names, prompt input packages consume
+snapshots, and Recent Changes compares snapshot stanzas.
+
+## Inputs And Outputs
+
+Inputs:
+
+- ordered `module.ConfigItem` values from report definitions or config
+  overrides
+- `module.Output` values produced by module builders
+
+Outputs:
+
+- stable `module.ID` constants
+- typed option structs for registered modules
+- `module.Snapshot` with schema version `weatherreporter.modules.v1`
+- ordered snapshot outputs with module ID, stanza name, and typed value
+- typed stanza lookup through `module.StanzaValue`
+
+## Registered Module IDs
+
+The registry recognizes these IDs:
+
+- `metadata`
+- `current_conditions`
+- `narrative_forecast`
+- `hourly_forecast`
+- `derived_daily_summary`
+- `derived_daypart_summaries`
+- `precip_timing`
+- `alert_digest`
+- `area_forecast_discussion`
+- `weather_story`
+- `outdoor_windows`
+- `tomorrow_planning`
+
+Every registered module has a builder. Report composition entries that refer to
+unknown or unimplemented module IDs fail validation instead of being skipped.
+
+## Options
+
+Most modules use an empty options struct. `area_forecast_discussion` accepts:
+
+```yaml
+sections:
+  - product
+  - key_messages
+  - short_term
+  - long_term
+```
+
+An omitted or empty `sections` list includes all available discussion sections.
+Invalid option shapes fail during config normalization or composition
+validation.
+
+## Boundaries
+
+- This package owns module identifiers, config item envelopes, output
+  envelopes, snapshot validation, and typed stanza lookup.
+- It does not define report IDs, execute builders, fetch weather data, derive
+  forecast facts, write state, or invoke Scriptorium.
+
+## State Or Manifest Behavior
+
+`module.Snapshot` values are persisted by `internal/state` as JSON. Snapshot
+validation rejects missing schema version, missing module IDs, missing stanza
+names, duplicate module outputs, and duplicate stanza names while preserving
+output order.
+
+## Failure Behavior
+
+- Snapshot construction fails for duplicate module outputs or duplicate stanza
+  names.
+- Typed stanza lookup returns `found=false` for missing stanzas.
+- Typed stanza lookup wraps JSON marshal/decode failures with stanza context.
+
+## Tests
+
+Inspect:
+
+- `internal/module/module_test.go`
+- `internal/briefing/modules_test.go`
+- `internal/report/period_test.go`
+
+## Invariants
+
+- `internal/module` does not import `internal/report`.
+- Module IDs are stable strings.
+- Each emitted module output has exactly one stanza name and one typed value.
+- Snapshot output order is caller-owned and preserved.

docs/internal/prompt-input.md

@@ -0,0 +1,121 @@
+# Prompt Input Internals
+
+This document describes YAML prompt data package construction in
+`internal/promptinput`.
+
+## Purpose
+
+`internal/promptinput` converts report metadata, an ordered module snapshot,
+Recent Changes, and source warnings into the `data_package` file passed to
+Scriptorium.
+
+The persisted data package is YAML with schema version
+`weatherreporter.data_package.v2`. It is separate from the JSON module snapshot
+used for inspection and comparison.
+
+## Inputs And Outputs
+
+Inputs:
+
+- report metadata from app/state orchestration
+- `module.Snapshot`
+- optional `[]changes.Change`
+
+Outputs:
+
+- `promptinput.Package` with schema version, RunID, report metadata, named
+  module stanzas grouped for prompt presentation, Recent Changes, and source
+  warnings
+- YAML bytes from `promptinput.MarshalYAML`
+- YAML file written atomically by `promptinput.Save`
+
+The YAML shape includes:
+
+```yaml
+schema_version: weatherreporter.data_package.v2
+run_id: <run_id>
+report:
+  id: <report_id>
+  prompt_id: <prompt_id>
+briefing:
+  metadata: {}
+  applicable_risk_products:
+    alert_digest: {}
+  derived_summaries:
+    derived_daily_summary: {}
+    derived_daypart_summaries: {}
+    precip_timing: {}
+    outdoor_windows: {}
+  narrative_products:
+    narrative_forecast: {}
+    area_forecast_discussion: {}
+    weather_story: {}
+  raw_data:
+    current_conditions: {}
+    hourly_forecast: {}
+recent_changes:
+  items: []
+```
+
+The `briefing` mapping keeps `metadata` directly under `briefing` and groups
+weather module stanzas under prompt-facing categories. This grouping is a YAML
+presentation concern only: module snapshots remain flat, and loaded
+`promptinput.Package` values expose flat stanza names in `Briefing.Values`.
+Within each category, stanza order follows the module snapshot output order.
+
+Current categories are:
+
+- `applicable_risk_products`: location-applicable alerts, warnings, outlooks,
+  discussions, and similar risk products.
+- `derived_summaries`: deterministic summaries and calculated report facts.
+- `narrative_products`: official narrative text products and forecast stories.
+- `raw_data`: minimally transformed underlying weather data.
+
+## Boundaries
+
+- This package owns prompt package schema, YAML marshaling, YAML loading, and
+  validation.
+- It does not fetch weather data, derive forecast summaries, execute modules,
+  find prior snapshots, compare changes, choose artifact paths, or invoke
+  Scriptorium.
+
+## Config Fields Used
+
+None directly. Config-derived values such as timezone, units, and prompt
+location are already present in report metadata and module stanzas before this
+package runs.
+
+## External Adapters Used
+
+None.
+
+## State Or Manifest Behavior
+
+`promptinput.Save` writes YAML atomically. Managed workspace paths are owned by
+`internal/state`.
+
+## Skip And Resume Behavior
+
+None. Recent Changes is always present as an `items` list and may be empty.
+
+## Failure Behavior
+
+Validation fails before render preflight when required top-level fields are
+missing or inconsistent, when the valid period is invalid, or when no module
+stanzas are present. Save failures include filesystem operation and path
+context.
+
+## Tests
+
+Inspect:
+
+- `internal/promptinput/package_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Scriptorium receives structured YAML through `--input data_package=<path>`.
+- Module stanza order is deterministic within each prompt-facing category.
+- Every non-metadata module stanza has exactly one prompt-input category.
+- Recent Changes are provided by `internal/changes`; this package does not
+  infer changes from rendered report text.

docs/internal/report-registry.md

@@ -0,0 +1,99 @@
+# Report Registry Internals
+
+This document describes report identity, valid-period resolution, batch
+membership, output naming, artifact grouping, and comparison declarations in
+`internal/report`.
+
+## Purpose
+
+`internal/report` is the canonical source for report definitions. App, state,
+module building, and CLI wiring consume resolved definitions instead of owning
+report identity policy themselves.
+
+## Definition Fields
+
+Each report definition declares:
+
+- report ID and display name
+- Scriptorium prompt ID
+- valid-period resolver
+- comparison strategy
+- managed artifact group
+- batch output copy filename
+- generated-report eligibility
+- prior-report compatibility list
+- morning or evening batch membership
+- default ordered module composition
+
+## Reports
+
+| Report | ID | Prompt | Artifact group | Batch copy | Prior compatibility |
+| --- | --- | --- | --- | --- | --- |
+| Daily Today | `daily_today` | `weather.daily_report` | `daily` | `daily.md` | Daily Today, Daily Tomorrow |
+| Daily Tomorrow | `daily_tomorrow` | `weather.daily_report` | `daily` | `tomorrow.md` | Daily Today, Daily Tomorrow |
+| 3-Day Outlook | `three_day` | `weather.three_day_outlook` | `three-day` | `three-day.md` | 3-Day Outlook |
+| Weekend Outlook | `weekend` | `weather.weekend_outlook` | `weekend` | `weekend.md` | Weekend Outlook |
+| Storm Report | `storm` | `weather.storm_report` | `storm` | `storm.md` | Storm Report |
+
+All report definitions are eligible for generation.
+
+## Valid Periods
+
+- Daily Today covers the selected local civil day, or the current local civil
+  day when no date override is supplied.
+- Daily Tomorrow covers the next local civil day from generation time.
+- 3-Day Outlook covers the interval from generation time through local midnight
+  three days later.
+- Weekend Outlook covers the upcoming weekend window and is not scheduled for
+  Sunday morning batch resolution.
+- Storm Report covers an explicit event window supplied by the caller.
+
+Storm event windows can be parsed from local `YYYY-MM-DDTHH:MM` timestamps in
+the configured timezone or RFC3339 timestamps with explicit offsets. End time
+must be after start time.
+
+## Boundaries
+
+`internal/report` defines report metadata and time coverage. It does not fetch
+weather data, build module values, compare snapshot contents, write state,
+parse CLI flags, or invoke Scriptorium.
+
+The CLI owns public command names. The app maps those command names to report
+IDs, then uses the registry for report policy.
+
+## Config Fields Used
+
+The app supplies `weather_api.timezone` as a loaded `time.Location`. Batch
+output path copying uses batch output names from report definitions.
+
+## State And App Usage
+
+- State paths use `ArtifactGroup`.
+- Batch output copies use `BatchOutputName`.
+- Generation checks `Generated`.
+- Module composition defaults use `Modules`.
+- Prior lookup checks `CompatiblePriorIDs` and the comparison strategy.
+- RunIDs include the resolved report ID.
+
+## Failure Behavior
+
+- Unknown report IDs and batch names return actionable errors.
+- Weekend Outlook resolution returns an error when resolved directly on Sunday.
+- Storm Report resolution requires start and end, with end after start.
+
+## Tests
+
+Inspect:
+
+- `internal/report/period_test.go`
+- `internal/app/app_test.go`
+- `internal/cli/root_test.go`
+
+## Invariants
+
+- Report selection goes through the registry.
+- Daily Today and Daily Tomorrow both use `weather.daily_report`.
+- Valid periods are half-open intervals independent of rendered report text.
+- Artifact grouping, batch output filenames, generated-report eligibility,
+  default module composition, comparison compatibility, and comparison strategy
+  are declared by report definition.

docs/internal/scriptorium-adapter.md

@@ -0,0 +1,101 @@
+# Scriptorium Adapter Internals
+
+This document describes the subprocess adapter in
+`internal/adapters/scriptorium`.
+
+## Purpose
+
+The adapter runs `scriptorium render` for prompt preflight and `scriptorium run`
+for Markdown report generation. It isolates subprocess execution, argv
+construction, timeout handling, output capture, and exit-code interpretation
+from app and domain packages.
+
+## Inputs And Outputs
+
+Inputs:
+
+- prompt ID
+- YAML prompt input data package path
+- report output path for `run`
+- configured binary, config path, profile, timeout, and extra arguments
+- context for cancellation
+
+Outputs:
+
+- argv used for execution
+- captured stdout and stderr
+- truncation flags for captured output
+- exit code
+- report output path for `run`
+
+## Boundaries
+
+`internal/adapters/scriptorium` owns Scriptorium command construction and
+subprocess execution. It does not choose report types, build prompt input,
+fetch weather data, decide workflow order, or persist workflow metadata.
+
+The adapter exposes request and result structs for render and run operations.
+State persistence uses a state-owned preflight artifact shape; app
+orchestration converts render results before saving.
+
+## Config Fields Used
+
+- `scriptorium.binary`
+- `scriptorium.config_path`
+- `scriptorium.profile`
+- `scriptorium.timeout`
+- `scriptorium.extra_args`
+
+## Commands
+
+Render preflight argv starts with:
+
+```text
+scriptorium render --prompt <prompt_id> --input data_package=<path> --format json
+```
+
+Report generation argv starts with:
+
+```text
+scriptorium run --prompt <prompt_id> --input data_package=<path> --out <path>
+```
+
+Configured `--config` and `--profile` flags are inserted after the subcommand
+and before prompt-specific arguments. Extra arguments are appended after the
+built-in arguments.
+
+## Execution Behavior
+
+The adapter runs commands without shell interpolation. The same private
+execution path is used by render and run after command-specific request
+validation and argv construction.
+
+When `scriptorium.timeout` is greater than zero, each subprocess call uses a
+context with that timeout. Stdout and stderr are captured separately, capped at
+1 MiB each, and marked as truncated when the cap is reached.
+
+## Failure Behavior
+
+- Missing prompt ID or data package path returns an error before subprocess
+  execution.
+- Missing run output path returns an error before subprocess execution.
+- Subprocess start errors, context cancellation, and timeouts are wrapped with
+  operation context by the caller-facing method.
+- Nonzero render and run exits return the captured result plus an error
+  containing the exit code and stderr.
+
+## Tests
+
+Inspect:
+
+- `internal/adapters/scriptorium/runner_test.go`
+- `internal/app/app_test.go`
+- `internal/cli/root_test.go`
+
+## Invariants
+
+- No shell interpolation is used.
+- The Scriptorium input name is `data_package`.
+- The file at the data package path is YAML produced by `internal/promptinput`.
+- Render and run preserve command-specific result structs.
+- Scriptorium-specific flags stay inside adapter and config boundaries.

docs/internal/state.md

@@ -0,0 +1,124 @@
+# State Internals
+
+This document describes filesystem state in `internal/state`.
+
+## Purpose
+
+`internal/state` owns managed workspace paths, atomic JSON writes, persisted
+metadata, prior snapshot lookup, and read-only artifact inspection helpers.
+
+## Inputs And Outputs
+
+Inputs:
+
+- workspace configuration
+- resolved report definition and valid period
+- module snapshot
+- prompt input data package
+- preflight artifact
+- rendered report path preparation request
+- RunID for inspection lookups
+
+Outputs:
+
+- module snapshot JSON path
+- prompt input data package YAML path
+- render preflight JSON path
+- managed Markdown report path
+- metadata JSON path
+- prior comparable snapshot metadata
+- loaded module snapshot or data package
+- recent report records for inspection
+
+## Boundaries
+
+`internal/state` owns local filesystem layout, path validation, durable writes,
+metadata reads, prior lookup, and report listing. It does not fetch weather
+data, derive forecasts, build prompt input content, compare module contents,
+invoke Scriptorium, import adapter result types, or parse CLI flags.
+
+Preflight persistence uses the state-owned `PreflightArtifact` shape. The app
+converts adapter render results into that shape before saving.
+
+## Config Fields Used
+
+- `workspace.root`
+- `workspace.snapshots_dir`
+- `workspace.reports_dir`
+- `workspace.data_packages_dir`
+- `workspace.preflight_dir`
+- `workspace.notifications_dir`
+
+Workspace subdirectories must be relative paths that stay under
+`workspace.root`.
+
+## Managed Layout
+
+Paths are derived from the resolved report definition's artifact group, the
+valid-period start date for dated artifacts, and the RunID.
+
+```text
+<workspace.root>/
+  snapshots/<artifact_group>/<YYYY-MM-DD>/<run_id>.modules.json
+  snapshots/<artifact_group>/<YYYY-MM-DD>/<run_id>.metadata.json
+  data-packages/<artifact_group>/<YYYY-MM-DD>/<run_id>.data_package.yaml
+  preflight/<artifact_group>/<YYYY-MM-DD>/<run_id>.render.json
+  notifications/<artifact_group>/<YYYY-MM-DD>/<run_id>.distributor.json
+  reports/<artifact_group>/<run_id>.md
+```
+
+Metadata is stored beside module snapshots and links the module snapshot, data
+package, preflight, report paths, notification path when attempted, and
+configured prompt location. Report listing walks metadata files under the
+snapshots directory.
+
+## Prior Lookup
+
+Prior snapshot lookup reads stored metadata through the shared lookup path and
+selects the latest earlier snapshot whose report ID is compatible with the
+current report definition.
+
+- Daily Today and Daily Tomorrow are compatible with each other for the same
+  valid local date.
+- 3-Day Outlook compares with prior 3-Day snapshots for the same valid local
+  date.
+- Weekend Outlook compares with prior Weekend snapshots for the same weekend
+  window.
+- Storm Report has no prior lookup because explicit event-window comparison is
+  not searched by the filesystem store.
+
+## Writes And Inspection
+
+Durable JSON writes use shared atomic file helpers. Managed Markdown reports are
+prepared by creating their parent directory; Scriptorium writes the report body
+to the prepared path. Extra Markdown copies are handled by app orchestration.
+Distributor notification debug artifacts are written atomically when
+notification is attempted and include rendered distributor pipeline ID, bundle
+ID, idempotency key, bundle paths, upload status, latest run status, and
+redacted errors.
+
+Inspection helpers read existing metadata, module snapshot, and data package
+files. Missing metadata directories return no inspection records or no prior
+snapshot rather than creating state.
+
+## Failure Behavior
+
+- Invalid workspace paths return validation errors.
+- Missing required metadata fields prevent metadata writes.
+- JSON writes use a temporary file followed by rename where practical.
+- Read and decode failures include path context.
+- Unknown RunIDs produce an actionable lookup error.
+
+## Tests
+
+Inspect:
+
+- `internal/state/filesystem_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Managed paths stay under the configured workspace root.
+- Artifact grouping comes from report definitions.
+- Metadata links artifacts produced for a run.
+- Prior lookup is based on structured metadata, not rendered report text.

docs/internal/weather-data.md

@@ -0,0 +1,88 @@
+# Weather Data Internals
+
+This document describes Weather API ingestion into `weatherdata.Bundle`.
+
+## Purpose
+
+`internal/adapters/weatherapi` fetches normalized weather data from one
+configured Weather API endpoint and assembles the bundle consumed by forecast
+derivation and module builders. Module builders expose normalized current
+conditions and weather story context when those sources are available.
+
+## Inputs And Outputs
+
+Inputs:
+
+- `config.Config` with Weather API URL, timeout, format, units, timezone,
+  precision, and missing-source policy
+- HTTP responses using the Weather API `data` envelope
+
+Outputs:
+
+- `weatherdata.Bundle` with observation, current conditions, hourly forecast,
+  narrative forecast, active alerts, discussion, latest weather story, source
+  records, and source warnings
+- optional saved bundle JSON through app fetch helpers
+
+## Boundaries
+
+- The adapter owns HTTP calls, response-envelope handling, source hashing, and
+  decoding into internal bundle types.
+- It does not derive dayparts, resolve report periods, build module values, compare
+  snapshots, write report state, or invoke Scriptorium.
+
+## Config Fields Used
+
+- `weather_api.base_url`
+- `weather_api.timeout`
+- `weather_api.format`
+- `weather_api.units`
+- `weather_api.timezone`
+- `weather_api.precision`
+- `missing_source.default`
+- `missing_source.sources`
+
+## External Adapters Used
+
+- Weather API HTTP service
+
+See [Weather API integration](../integrations/weatherapi.md) for the external
+contract used by this project.
+
+## State Or Manifest Behavior
+
+The adapter records source name, endpoint, query, fetch time, source timestamps
+when available, SHA-256 hash over compact raw `data` JSON, missing status, and
+source warnings. Successful `data: null` responses from `/alerts/active`
+represent a checked empty active-alert list, not a missing source.
+`app.FetchAndSaveBundle` can write bundle JSON atomically for inspection.
+
+## Skip And Resume Behavior
+
+No resume behavior. Optional missing or malformed sources may be omitted,
+warned, or treated as errors according to missing-source policy. Hourly forecast
+data is required and cannot be skipped.
+
+## Failure Behavior
+
+- Missing or invalid `weather_api.base_url` prevents client construction.
+- HTTP errors, response read failures, and envelope decode failures include
+  endpoint context.
+- Missing hourly data or hourly forecasts with no periods fail bundle fetch.
+- Optional sources follow missing-source policy.
+- Explicit `data: null` from `/alerts/active` produces an empty, non-missing
+  alert run.
+
+## Tests
+
+Inspect:
+
+- `internal/adapters/weatherapi/client_test.go`
+- `internal/app/app_test.go`
+
+## Invariants
+
+- Weather facts come from normalized source data.
+- Full hourly and narrative products are fetched; Go owns report-period
+  selection.
+- Source provenance and warnings remain inspectable downstream.

docs/operations.md

@@ -0,0 +1,257 @@
+# Weatherreporter Operations
+
+This guide covers normal operation, generated artifacts, inspection, recovery,
+and operational caveats. For symptom-specific diagnosis, see
+[Troubleshooting](troubleshooting.md).
+
+## Normal Workflow
+
+Generation commands:
+
+```text
+weatherreporter generate daily --date 2026-05-29
+weatherreporter generate tomorrow
+weatherreporter generate three-day
+weatherreporter generate weekend
+weatherreporter generate storm --start 2026-05-29T18:00 --end 2026-05-30T06:00
+```
+
+Each command resolves a report period, fetches a Weather API bundle, builds a
+JSON module snapshot, builds a YAML prompt input data package, runs
+`scriptorium render`, runs `scriptorium run`, and writes managed artifacts under
+the configured workspace.
+When distributor notification is enabled, weatherreporter uploads the managed
+Markdown report after `scriptorium run` succeeds and final metadata is saved.
+`--out PATH` writes an extra Markdown copy for the current generated report; it
+is not used as the distributor upload source.
+
+Batch commands:
+
+```text
+weatherreporter run morning
+weatherreporter run evening
+```
+
+`run morning` generates Daily Today and the 3-Day Outlook, plus Weekend Outlook
+except on Sunday. `run evening` generates the Tomorrow Planning Brief. Batch
+commands print a JSON summary to stdout, write compact per-report status lines
+to stderr, continue independent reports after one report fails, and return
+nonzero when any report failed. When notification is configured, the summary and
+status lines include notification status, accepted distributor run ID, or
+notification error fields for each attempted report. `--out-dir PATH` writes
+extra Markdown copies using report default filenames such as `daily.md`,
+`three-day.md`, `weekend.md`, and `tomorrow.md`; these copies are not used as
+distributor upload sources.
+
+## Filesystem Layout
+
+The default workspace root is `workspace`.
+
+```text
+workspace/
+  snapshots/
+    daily/
+      YYYY-MM-DD/
+        <run_id>.modules.json
+        <run_id>.metadata.json
+    three-day/
+      YYYY-MM-DD/
+        <run_id>.modules.json
+        <run_id>.metadata.json
+    weekend/
+      YYYY-MM-DD/
+        <run_id>.modules.json
+        <run_id>.metadata.json
+    storm/
+      YYYY-MM-DD/
+        <run_id>.modules.json
+        <run_id>.metadata.json
+  data-packages/
+    daily/
+      YYYY-MM-DD/
+        <run_id>.data_package.yaml
+    three-day/
+      YYYY-MM-DD/
+        <run_id>.data_package.yaml
+    weekend/
+      YYYY-MM-DD/
+        <run_id>.data_package.yaml
+    storm/
+      YYYY-MM-DD/
+        <run_id>.data_package.yaml
+  preflight/
+    daily/
+      YYYY-MM-DD/
+        <run_id>.render.json
+    three-day/
+      YYYY-MM-DD/
+        <run_id>.render.json
+    weekend/
+      YYYY-MM-DD/
+        <run_id>.render.json
+    storm/
+      YYYY-MM-DD/
+        <run_id>.render.json
+  notifications/
+    daily/
+      YYYY-MM-DD/
+        <run_id>.distributor.json
+    three-day/
+      YYYY-MM-DD/
+        <run_id>.distributor.json
+    weekend/
+      YYYY-MM-DD/
+        <run_id>.distributor.json
+    storm/
+      YYYY-MM-DD/
+        <run_id>.distributor.json
+  reports/
+    daily/
+      <run_id>.md
+    three-day/
+      <run_id>.md
+    weekend/
+      <run_id>.md
+    storm/
+      <run_id>.md
+```
+
+Managed artifact filenames use the RunID, so repeated runs for the same valid
+period do not overwrite each other.
+
+## RunID And Metadata
+
+RunIDs are based on generation time plus report ID:
+
+```text
+20260529T100000.123456789Z_daily_today
+```
+
+Each generated report writes metadata that links:
+
+- RunID, report ID, variant, and prompt ID
+- generation time, timezone, and valid period
+- source location, source hashes, and source warnings
+- module snapshot path
+- prompt input data package path
+- preflight output path
+- managed Markdown report path
+- distributor notification debug artifact path, when notification is attempted
+
+Batch summaries include report status, error text when applicable, notification
+outcome when attempted, valid period, and known artifact paths for each
+attempted report. Notification fields are `notificationStatus`,
+`notificationRunId`, and `notificationError`.
+
+## Distributor Notification
+
+Distributor notification is configured with `notify.distributor` and is
+disabled by default. When enabled, weatherreporter uploads the managed Markdown
+report path recorded in the report result and metadata. That single source file
+can be mapped to one or more configured bundle paths. By default, it is mapped
+to one dated report path. Extra copies written by `--out` or `--out-dir` are
+operator conveniences only.
+
+The rendered pipeline ID selects the configured distributor `http_upload`
+workflow. The default bundle ID is a stable logical source identity derived from
+producer name, location ID, and report ID:
+
+```text
+weatherreporter.{location_id}.{report_id}
+```
+
+The default idempotency key appends RunID to the rendered bundle ID so each
+report generation has a distinct retry identity. The default bundle path uses
+the valid-period start date, artifact group, and RunID. Distributor owns
+destination merge, retention, and derived snapshot behavior such as `latest`.
+
+Notification happens after final metadata save. Weather API, module snapshot,
+data-package, render preflight, Scriptorium run, and metadata-save failures do
+not trigger notification. A notification failure fails that report.
+In a batch, other reports continue, the failed report includes notification
+fields in the JSON summary, and the batch returns nonzero.
+
+Each notification attempt writes a debug artifact under `notifications/`. The
+artifact records the rendered pipeline ID, bundle ID, idempotency key, managed
+source path, bundle-relative paths, bundle created timestamp, accepted upload
+response, and the latest distributor run status response when available.
+Weatherreporter polls status until distributor reports `succeeded` or `failed`,
+or until the configured notification timeout expires. The run status includes
+the distributor status, error text, and raw run report JSON, which can show
+actions such as `replace_older`, `skip_same`, `skip_destination_newer`, or
+`failed`. Token values are not written.
+
+Weatherreporter is responsible for selecting the managed Markdown report,
+constructing a source bundle, and submitting it to the configured distributor
+HTTP endpoint. Distributor remains responsible for destination routing,
+publication, and any downstream Markdown-to-HTML transformation. Distributor
+leaves destination files alone when they are not tracked by a newly uploaded
+bundle, so existing uploaded dated report paths can remain available.
+
+## Inspection
+
+Inspection commands read existing workspace artifacts and emit JSON to stdout.
+They do not fetch weather data or run `scriptorium`.
+
+```text
+weatherreporter inspect reports --limit 10
+weatherreporter inspect metadata RUN_ID
+weatherreporter inspect modules RUN_ID
+weatherreporter inspect data-package RUN_ID
+weatherreporter inspect prior RUN_ID
+weatherreporter inspect sources RUN_ID
+```
+
+Use `inspect reports` to find RunIDs and artifact paths. Use
+`inspect metadata` to see the artifact links recorded for a run. Use
+`inspect modules` to review the persisted ordered module snapshot, and
+`inspect data-package` to review the structured prompt package used for
+rendering. Use `inspect prior` to see the prior comparable snapshot selected for
+Recent Changes, or `null` when none exists. Use `inspect sources` to review
+source provenance and warnings without dumping full weather payloads.
+
+## Recent Changes
+
+Recent Changes are computed from structured module snapshots, not rendered
+Markdown or YAML text.
+
+Daily Today and Daily Tomorrow can compare with each other when they cover the
+same valid local date. 3-Day Outlook compares with prior compatible 3-Day
+snapshots for the same valid local date. Weekend Outlook compares with prior
+compatible Weekend snapshots for the same weekend window. Storm Report leaves
+Recent Changes empty.
+
+When no prior comparable snapshot exists, or no configured threshold is crossed,
+`recentChanges.items` is empty.
+
+## Recovery
+
+A failed generation run may still leave useful artifacts:
+
+- If `scriptorium render` returns a result with a nonzero exit code, the
+  preflight JSON and metadata are written for inspection.
+- If `scriptorium run` exits nonzero after writing a report, the managed report
+  and metadata remain available.
+- If distributor notification fails, report artifacts and final metadata remain
+  available, but the report or batch command returns nonzero.
+- For batch commands, inspect the stdout JSON summary first, then inspect the
+  artifact paths for each failed report.
+
+For a bad report, start with:
+
+```text
+weatherreporter inspect metadata RUN_ID
+weatherreporter inspect sources RUN_ID
+weatherreporter inspect modules RUN_ID
+weatherreporter inspect data-package RUN_ID
+weatherreporter inspect prior RUN_ID
+```
+
+## Operational Caveats
+
+- The application uses one configured Weather API endpoint.
+- The application writes local filesystem state only.
+- The application does not implement resume, cleanup, archive, remote storage,
+  daemon operation, or automatic storm monitoring.
+- Generated reports and Scriptorium stderr can contain sensitive operational
+  context. Store workspace artifacts with appropriate filesystem permissions.

docs/policy/architecture.md

@@ -3,16 +3,22 @@
 This document defines the development principles for this Go project. It is inward-facing: developers and LLM coding agents should use it to preserve the project’s shape, boundaries, and invariants as the code evolves.
 
 ## weatherreporter
-`weatherreporter` is a deterministic weather briefing and report-preparation application. It consumes normalized weather data from the internal weatherfeeder-backed API, derives report-specific briefing packages, compares those packages against prior snapshots, and invokes an external prompt runner to produce human-facing reports.
+`weatherreporter` is a deterministic weather briefing and report-preparation application. It consumes normalized weather data from the internal weatherfeeder-backed API, derives report-specific module snapshots and prompt packages, compares module snapshots against prior runs, and invokes an external prompt runner to produce human-facing reports.
 
-The application should keep meteorological data selection, daypart grouping, threshold detection, forecast-period resolution, and recent-change comparison inside Go domain packages. LLM prompts should receive curated briefing packages rather than raw unbounded source payloads wherever practical.
+The application should keep meteorological data selection, daypart grouping, threshold detection, forecast-period resolution, and recent-change comparison inside Go domain packages. LLM prompts should receive curated module-based prompt packages rather than raw unbounded source payloads wherever practical.
 
-Report types must be defined through a registry or equivalent mechanism. Each report definition should declare its report ID, prompt ID, valid-period resolver, briefing builder, comparison strategy, and output naming behavior. Avoid scattering report-type conditionals across CLI and orchestration code.
+Report types must be defined through a registry or equivalent mechanism. Each report definition should declare its report ID, prompt ID, valid-period resolver, module composition, comparison strategy, and output naming behavior. Avoid scattering report-type conditionals across CLI and orchestration code.
 
-Generated reports must be associated with explicit metadata, including report type, location, generation time, valid period, source product timestamps or hashes, briefing snapshot path, and output path. Recent Changes must be based on structured snapshot comparison rather than comparison of rendered Markdown report text.
+Generated reports must be associated with explicit metadata, including report type, location, generation time, valid period, source product timestamps or hashes, module snapshot path, and output path. Recent Changes must be based on structured snapshot comparison rather than comparison of rendered Markdown report text.
 
 `scriptorium` is an external adapter, not domain logic. Subprocess execution must be isolated under `internal/adapters/scriptorium`, use context-aware execution, avoid shell interpolation, capture actionable stderr, and keep scriptorium-specific flags from leaking into domain packages.
 
+`distributor` is also an external adapter. Upload behavior must be isolated
+under `internal/adapters/distributor`, dependency types from the distributor
+module must not leak outside that adapter, and the selected upload source must
+be the managed Markdown report rather than optional output copies or broad
+workspace scans.
+
 ## Project Shape
 
 Default to a small, explicit, dependency-light Go application. Keep the design modular enough to test and change safely, but do not add abstraction unless it protects a real boundary or enables a real extension point.
@@ -46,16 +52,15 @@ Centralize configuration loading, processing, precedence, defaults, and validati
 
 The goal is to make configuration discoverable and avoid implicit or hidden operational values. User-visible defaults and cross-package operational defaults should be defined in `internal/config/defaults.go`.
 
-Unless documented otherwise, precedence is:
+Configuration precedence is:
 
 1. CLI flags
-2. environment variables
-3. configuration file
-4. built-in defaults
+2. configuration file
+3. built-in defaults
 
 Prefer YAML configuration unless the project has a strong reason to use another format. Config files should be discovered at `/usr/local/etc/<app_name>/config.yml`, with a CLI override via `--config`.
 
-Configuration files should not contain raw secrets unless the application is explicitly designed for that. Prefer environment variables or secret files for secrets.
+Configuration files should not contain raw secrets unless the application is explicitly designed for that. Prefer environment variables or secret files for secrets. File-backed secrets are loaded through `secrets.directory`; secret values must not be logged, persisted, or included in user-facing output.
 
 ## Adapters and External Integrations
 
@@ -65,13 +70,17 @@ External adapters belong under `internal/adapters/<name>`. If an adapter uses an
 
 Adapters should be thin. Domain decisions belong in application/domain packages, not inside adapter glue.
 
-## Modules, Stages, and Registries
+## Components and Registries
 
-When the application has stages or modules, each major stage/module should live in its own package and have an explicit input/output contract.
+When the application has major workflow components, each component should live
+near the package that owns its contract and have explicit inputs and outputs.
 
-The orchestrator should be able to compose, skip, resume, or run individual stages/modules when their prerequisites are satisfied. Ordering should be explicit: use a default sequence, dependency graph, or documented orchestration rule.
+The orchestrator should compose components in an explicit order using a default
+sequence, dependency graph, or documented orchestration rule.
 
-If users can select modules, stages, validators, renderers, or adapters, selection should go through a registry or equivalent mechanism rather than scattered conditionals.
+If users can select components, validators, renderers, or adapters, selection
+should go through a registry or equivalent mechanism rather than scattered
+conditionals.
 
 ## Embedded Assets
 
@@ -87,11 +96,15 @@ Use structured logging where practical. Logs should describe operations, paths,
 
 ## Context, Timeouts, and Cancellation
 
-Long-running operations should accept `context.Context`. External calls, subprocesses, HTTP requests, storage operations, and multi-stage workflows should respect cancellation and timeouts.
+Long-running operations should accept `context.Context`. External calls,
+subprocesses, HTTP requests, storage operations, and multi-step workflows should
+respect cancellation and timeouts.
 
 ## State, Files, and Safety
 
-If the application writes durable state, writes should be atomic where practical. Multi-step workflows should preserve enough state to support inspection, retry, or resume after failure.
+If the application writes durable state, writes should be atomic where
+practical. Multi-step workflows should preserve enough state to support
+inspection and retry diagnosis after failure.
 
 Code that deletes, moves, or overwrites files must use narrow, explicit paths. Avoid broad parent-directory operations. Cleanup that can cause data loss must be opt-in.
 
@@ -99,11 +112,14 @@ Code that deletes, moves, or overwrites files must use narrow, explicit paths. A
 
 Core logic should be testable without real external services. Use fakes, fixtures, or local test doubles for adapters where practical.
 
-Config examples should be load-tested. Important CLI workflows should have parser or command tests. Stage/module contracts should have focused tests that do not require running the full application unless end-to-end coverage is intentional.
+Config examples should be load-tested. Important CLI workflows should have
+parser or command tests. Component contracts should have focused tests that do
+not require running the full application unless end-to-end coverage is
+intentional.
 
 ## Documentation
 
 Documentation should follow the project documentation policy. Keep user docs focused on implemented behavior. Put future, planned, or aspirational work only under `docs/roadmap/`.
 
-When changing architecture, config, CLI behavior, adapters, or stage/module contracts, update the relevant docs and examples in the same change.
-
+When changing architecture, config, CLI behavior, adapters, or component
+contracts, update the relevant docs and examples in the same change.

docs/policy/development.md

@@ -1,691 +1,204 @@
-# Weatherreporter Package Layout
+# Development Policy
 
-This document defines the proposed package layout for `weatherreporter`, a Go application that prepares human-facing weather reports from normalized weather data collected by `weatherfeeder` and rendered through `scriptorium`.
+This document is the contributor workflow policy for `weatherreporter`.
+Developers and LLM coding agents should use it with
+`docs/policy/architecture.md` and `docs/policy/documentation.md`.
 
-The application should remain a small, explicit, dependency-light Go program. Domain logic should live outside CLI, transport, and external-adapter packages. External systems should be isolated behind narrow adapters. Report-specific behavior should be selected through a registry or equivalent mechanism rather than scattered conditionals.
+## Repository Layout
 
-## Architectural Summary
+- `cmd/weatherreporter`: binary entry point.
+- `internal/app`: orchestration for generation, batches, fetch helpers, and
+  inspection.
+- `internal/cli`: command parsing, flag handling, help text, and JSON output.
+- `internal/config`: configuration structs, defaults, loading, overrides, and
+  validation.
+- `internal/fileutil`: shared atomic filesystem write and copy helpers.
+- `internal/adapters/distributor`: Distributor upload adapter.
+- `internal/adapters/weatherapi`: Weather API HTTP adapter.
+- `internal/adapters/scriptorium`: Scriptorium subprocess adapter.
+- `internal/weatherdata`: normalized weather source facts, source metadata, and
+  source warnings.
+- `internal/forecast`: deterministic forecast derivation.
+- `internal/facts`: collected and derived report fact contracts.
+- `internal/module`: module IDs, config items, output envelopes, and snapshots.
+- `internal/report`: report definitions, valid periods, batches, output names,
+  and comparison declarations.
+- `internal/briefing`: prompt-facing module value builders and module registry.
+- `internal/changes`: structured Recent Changes comparison.
+- `internal/promptinput`: Scriptorium `data_package` construction and
+  validation.
+- `internal/state`: filesystem paths, atomic JSON writes, metadata, lookup, and
+  inspection support.
+- `internal/timeutil`: clock, date, timezone, and period helpers.
+- `docs`: user, operator, developer, integration, internal, policy, and roadmap
+  documentation.
+- `examples`: maintained copyable examples.
 
-`weatherreporter` is a deterministic weather briefing and report-preparation application. It should:
+## Local Validation
 
-1. Fetch normalized weather data from a single configured internal weather API endpoint backed by `weatherfeeder`.
-2. Derive report-specific briefing packages from the normalized forecast bundle.
-3. Compare current briefing snapshots against prior comparable snapshots to produce optional Recent Changes.
-4. Build structured prompt input data packages for a specific report type.
-5. Invoke `scriptorium` as an external prompt runner.
-6. Persist the rendered Markdown report, briefing snapshot, prompt input package, and generation metadata.
+Use focused checks while editing and broader checks before committing:
 
-The preferred data flow is:
-
-```text
-weatherfeeder-backed internal API
-    -> weather API adapter
-    -> forecast bundle
-    -> report-specific briefing builder
-    -> recent-change comparison
-    -> prompt input data package
-    -> scriptorium subprocess adapter
-    -> Markdown report + metadata + stored snapshot
+```bash
+go test ./...
+go run ./cmd/weatherreporter --help
+git diff --check
 ```
 
-The application should not treat the LLM as the source of weather facts. The Go code should select the relevant data, compute daypart and period summaries, attach alerts and NWS context, identify meaningful changes, and send the LLM a curated briefing package. The LLM should synthesize and phrase the report for humans.
+Useful focused checks:
 
-## Proposed Directory Layout
-
-```text
-cmd/weatherreporter/
-  main.go
-
-internal/app/
-  generate.go
-  scheduled.go
-  storm.go
-
-internal/cli/
-  root.go
-  generate.go
-  run.go
-  inspect.go
-
-internal/config/
-  config.go
-  defaults.go
-  load.go
-  validate.go
-
-internal/adapters/weatherapi/
-  client.go
-  types.go
-
-internal/adapters/scriptorium/
-  runner.go
-  types.go
-
-internal/forecast/
-  bundle.go
-  dayparts.go
-  derive.go
-  select.go
-  thresholds.go
-
-internal/report/
-  definition.go
-  registry.go
-  period.go
-  daily.go
-  tomorrow.go
-  three_day.go
-  weekend.go
-  storm.go
-
-internal/briefing/
-  package.go
-  daily.go
-  tomorrow.go
-  three_day.go
-  weekend.go
-  storm.go
-
-internal/changes/
-  compare.go
-  thresholds.go
-  summary.go
-
-internal/state/
-  store.go
-  filesystem.go
-  metadata.go
-
-internal/promptinput/
-  build.go
-  schema.go
-
-internal/timeutil/
-  clock.go
-  periods.go
+```bash
+go test ./internal/cli ./internal/config
+go test ./internal/app ./internal/state
+go test ./internal/adapters/distributor ./internal/adapters/weatherapi ./internal/adapters/scriptorium
+go test ./internal/forecast ./internal/report ./internal/briefing ./internal/changes ./internal/promptinput
 ```
 
-This layout can be simplified during early prototyping if a package has only one file, but the package boundaries should remain conceptually stable.
+Run `gofmt -w` on changed Go files before committing.
 
-## Dependency Direction
+## Coding Conventions
 
-The intended dependency direction is:
+- Keep domain logic out of `cmd`, `internal/cli`, and adapter packages.
+- Prefer small explicit structs and functions over broad framework-style
+  abstractions.
+- Keep package APIs narrow and named around implemented behavior.
+- Return errors with operation, path, endpoint, report, or RunID context.
+- Do not log or expose secrets.
+- Use `context.Context` for external calls, subprocesses, and orchestrated
+  workflows that may be canceled.
+- Use atomic writes for durable JSON artifacts where practical.
+- Keep report selection and prompt IDs centralized in `internal/report`.
+- Keep Scriptorium argv construction inside `internal/adapters/scriptorium`.
+- Keep distributor package types and upload-client construction inside
+  `internal/adapters/distributor`.
+- Keep Weather API transport and envelope handling inside
+  `internal/adapters/weatherapi`.
 
-```text
-cmd/weatherreporter
-    -> internal/cli
-    -> internal/app
-    -> internal/config
-    -> internal/report
-    -> internal/briefing
-    -> internal/forecast
-    -> internal/changes
-    -> internal/state
-    -> internal/adapters/*
-```
+## Dependency Policy
 
-Rules:
+Prefer the Go standard library. Add dependencies only when they materially
+improve correctness, interoperability, security, or maintainability.
 
-- `cmd/weatherreporter` should only bootstrap the CLI.
-- `internal/cli` should parse commands and flags, then call `internal/app`.
-- `internal/app` should orchestrate workflows but avoid embedding detailed forecast logic.
-- `internal/adapters/*` should not contain domain policy.
-- `internal/forecast`, `internal/report`, `internal/briefing`, and `internal/changes` should be testable without real external services.
-- `internal/state` should expose a storage interface so filesystem state can later be replaced or supplemented.
-- `scriptorium` details should not leak outside `internal/adapters/scriptorium`.
+Current external dependencies:
 
-## Package Responsibilities
+- `gitea.maximumdirect.net/eric/distributor` for distributor source bundle
+  construction and HTTP upload client behavior.
+- `gopkg.in/yaml.v3` for YAML configuration parsing.
 
-### `cmd/weatherreporter`
+When adding a dependency:
 
-Entry point for the compiled binary.
+- explain why the standard library is not enough;
+- keep dependency types from leaking across unrelated package boundaries;
+- add tests for the behavior the dependency supports;
+- update this policy if the dependency becomes part of contributor workflow.
 
-Responsibilities:
+## Configuration Changes
 
-- Construct the root command from `internal/cli`.
-- Execute the command.
-- Handle final process exit behavior.
+Configuration is owned by `internal/config`.
 
-Non-responsibilities:
+When adding or changing a field:
 
-- No configuration loading details.
-- No forecast logic.
-- No direct calls to weather APIs, state stores, or `scriptorium`.
+- update `Config` and the nested config struct in `config.go`;
+- add or adjust defaults in `defaults.go` when the field has a safe default;
+- update loading or CLI override behavior in `load.go` only when needed;
+- validate required values and accepted ranges in `validate.go`;
+- add or update config tests;
+- update `docs/config.md` and maintained examples when the field is user
+  visible;
+- keep secrets out of example config files.
 
-### `internal/cli`
+Configuration precedence is:
 
-Defines the user-facing command tree, flags, arguments, and command wiring.
+1. CLI overrides supported by `config.LoadOptions`;
+2. configuration file values;
+3. built-in defaults.
 
-Responsibilities:
+The default config path is `/usr/local/etc/weatherreporter/config.yml`.
 
-- Define commands such as:
-  - `weatherreporter generate daily`
-  - `weatherreporter generate tomorrow`
-  - `weatherreporter generate three-day`
-  - `weatherreporter generate weekend`
-  - `weatherreporter generate storm`
-  - `weatherreporter run morning`
-  - `weatherreporter run evening`
-  - `weatherreporter inspect snapshot`
-- Use the Go standard library for CLI parsing unless future complexity justifies a dependency.
-- Parse flags such as `--config`, `--units`, `--tz`, `--out`, optional Daily `--date`, and storm `--start`/`--end`, then convert them into app-layer request structs.
-- Load configuration through `internal/config`.
-- Present concise user-facing errors.
+## CLI Changes
 
-Non-responsibilities:
+The CLI is owned by `internal/cli`.
 
-- No report-building logic.
-- No direct subprocess execution.
-- No direct weather API calls.
-- No state comparison logic.
+When adding or changing a command or flag:
 
-Suggested command shape:
+- update help text and parser behavior together;
+- convert parsed values into app-layer request structs;
+- keep domain decisions in `internal/app` or domain packages;
+- add parser or command tests in `internal/cli`;
+- update `docs/cli.md`;
+- update `docs/operations.md` or `docs/troubleshooting.md` when behavior affects
+  operators.
 
-```text
-weatherreporter generate daily --date 2026-05-29 --out ./daily.md
-weatherreporter generate tomorrow --out ./tomorrow.md
-weatherreporter generate three-day --out ./three_day.md
-weatherreporter generate weekend --out ./weekend.md
-weatherreporter generate storm --start 2026-05-29T18:00 --end 2026-05-30T06:00 --out ./storm.md
-weatherreporter run morning
-weatherreporter run evening
-```
+CLI commands should return concise actionable errors and avoid printing partial
+JSON when command construction fails.
 
-The MVP should not expose location selection. Source `locationId` and `locationName` values returned by the weather API may be retained as provenance.
+## Components And Adapters
 
-For `generate daily`, `--date` is optional. When provided, it must use `YYYY-MM-DD`; when omitted, it resolves to the current local date in the configured timezone.
+Use existing package boundaries before adding a package.
 
-### `internal/config`
+Add a new internal component only when it owns a distinct implemented contract.
+Define its inputs, outputs, state behavior, failure behavior, tests, and
+invariants in `docs/internal/`.
 
-Owns configuration structures, defaults, loading, precedence, and validation.
+Adapters should stay thin:
 
-Responsibilities:
+- HTTP adapters own transport, request construction, envelope handling, and
+  decode boundaries.
+- subprocess adapters own argv construction, timeout handling, stdout/stderr
+  capture, and exit-code interpretation.
+- adapter packages should not own report selection, forecast summarization,
+  Recent Changes, or prompt input schema decisions.
 
-- Define application configuration structs.
-- Provide built-in defaults in `defaults.go`.
-- Load YAML configuration from `/usr/local/etc/weatherreporter/config.yml` or a CLI-supplied path.
-- Use `gopkg.in/yaml.v3` for YAML parsing.
-- Apply precedence rules.
-- Validate required settings.
-- Normalize paths, durations, report settings, weather API units/timezone, missing-source policy, and daypart definitions.
+When an external contract changes, update the matching file under
+`docs/integrations/`.
 
-Suggested configuration areas:
+## Tests
 
-- Weather API base URL, timeout, units, timezone, precision, and missing-source policy.
-- `scriptorium` binary, config path, profile, timeout, and optional extra arguments.
-- Workspace and output directories.
-- Report enablement and output naming.
-- Daypart definitions.
-- Recent-change thresholds.
+Core tests must not require live Weather API, Scriptorium, or distributor
+services.
 
-Initial defaults:
+Preferred test patterns:
 
-- Weather API units: `us`.
-- Weather API timezone: `Chicago`.
-- Weather API format: `json`.
-- Missing-source policy: `warn`.
+- fake command runners for subprocess behavior;
+- `httptest.Server` for Weather API behavior;
+- fake distributor upload clients for notification behavior;
+- filesystem temp directories for state behavior;
+- deterministic clocks for report periods and RunIDs;
+- table tests for config validation, CLI parsing, period resolution, and
+  threshold behavior.
 
-Missing-source policy should support a global default and per-source overrides. Valid policy values are `error`, `warn`, and `none`.
+Add focused tests near the package that owns the behavior. Use app-level tests
+for workflow ordering, persistence, and cross-package contracts.
 
-Non-responsibilities:
+## Examples
 
-- No command execution.
-- No HTTP calls.
-- No report-building logic.
+Examples under `examples/` must be real, maintained, and free of secrets.
 
-### `internal/app`
+When updating examples:
 
-Application orchestration and top-level use cases.
+- use implemented config fields only;
+- avoid private endpoints and credentials;
+- keep comments short and operationally useful;
+- add or update validation coverage when a new example file is introduced;
+- link maintained examples from `docs/config.md`.
 
-Responsibilities:
+Do not add generated report examples unless they can be kept current without
+live external services.
 
-- Implement use cases such as:
-  - Generate one report.
-  - Run the morning batch.
-  - Run the evening batch.
-  - Generate a manual storm report.
-- Coordinate config, weather API adapter, report registry, briefing builders, state store, change comparison, prompt input builder, and `scriptorium` runner.
-- Enforce workflow order.
-- Ensure each generation run persists enough artifacts for inspection and future comparison.
+## Documentation Checklist
 
-The core generation workflow should be approximately:
+Documentation updates are part of behavior changes.
 
-```text
-resolve report definition
-resolve valid period
-fetch current weather bundle
-build current briefing package
-load prior comparable briefing snapshot
-compute recent changes
-build prompt input data package
-write data package
-run scriptorium render preflight
-invoke scriptorium run
-persist report metadata, briefing snapshot, data package, preflight output, and rendered report
-```
+Update:
 
-Non-responsibilities:
+- `README.md` for project orientation or quickstart changes;
+- `docs/cli.md` for command and flag changes;
+- `docs/config.md` for config fields, defaults, and precedence changes;
+- `docs/operations.md` for state, artifact, batch, inspection, and recovery
+  behavior;
+- `docs/troubleshooting.md` for recurring operator-facing failure modes;
+- `docs/internal/` for component contracts and invariants;
+- `docs/integrations/` for external Weather API, Scriptorium, or distributor
+  contract changes;
+- `docs/roadmap/` only for unimplemented or deferred work.
 
-- No detailed daypart calculations.
-- No direct parsing of NWS text unless delegated to domain packages.
-- No direct shell command construction outside the `scriptorium` adapter.
-
-### `internal/adapters/weatherapi`
-
-HTTP adapter for the internal weather API backed by `weatherfeeder`.
-
-Responsibilities:
-
-- Fetch normalized weather data from the configured API base URL.
-- Fan out to multiple weather API endpoints and assemble one internal `forecast.Bundle`.
-- Decode API responses into adapter-owned DTOs or directly into stable internal types if those types are intentionally owned by `weatherreporter`.
-- Apply request timeouts and context cancellation.
-- Apply configured query defaults, including `format=json`, `units=us`, and `tz=Chicago` unless overridden.
-- Fetch full `/forecast/hourly` and `/forecast/narrative` products, not day-slice endpoints, so Go domain code owns report-period selection.
-- Record per-source provenance: endpoint, query, fetch time, issued/updated time when available, SHA-256 over canonical/minified raw `data` JSON, warnings, and missing-source status.
-- Represent source warnings as first-class records with source name, code, severity, message, endpoint, and completeness impact.
-- Require hourly forecast data for normal scheduled reports.
-- Apply missing-source policy for `data:null`, malformed non-required sections, or unavailable upstream products.
-- Return actionable errors containing endpoint and operation context.
-
-Initial data categories:
-
-- Latest observation.
-- Current conditions.
-- Hourly forecast data.
-- NWS narrative forecast periods.
-- NWS alerts.
-- NWS forecast discussion.
-
-Stubbed source slots until upstream support exists:
-
-- Daily forecast data.
-- NWS weather story.
-
-Non-responsibilities:
-
-- No daypart grouping.
-- No Recent Changes comparison.
-- No prompt input construction.
-- No `scriptorium` calls.
-
-### `internal/adapters/scriptorium`
-
-Subprocess adapter for invoking `scriptorium`.
-
-Responsibilities:
-
-- Provide a narrow runner interface, such as:
-
-```go
-type Runner interface {
-    Render(ctx context.Context, req RenderRequest) (*RenderResult, error)
-    Run(ctx context.Context, req RunRequest) (*RunResult, error)
-}
-```
-
-- Execute `scriptorium render` for preflight/debug output without LLM generation.
-- Execute `scriptorium run` for report generation.
-- Run `scriptorium render` as an always-on preflight before `scriptorium run` for MVP generated reports.
-- Pass arguments as an argv slice, not through a shell.
-- Pass large prompt input as `--input data_package=<path>`.
-- Capture stdout/stderr with reasonable size limits.
-- Treat nonzero exits as actionable errors, including exit code `2` from `run`, which may still produce output.
-- Keep all `scriptorium`-specific flag details inside the adapter.
-
-Suggested command forms:
-
-```text
-scriptorium render \
-  --prompt weather.daily_report \
-  --input data_package=./workspace/data-packages/daily/2026-05-29T050000-0500.data_package.json \
-  --format json
-
-scriptorium run \
-  --prompt weather.daily_report \
-  --input data_package=./workspace/data-packages/daily/2026-05-29T050000-0500.data_package.json \
-  --out ./workspace/reports/daily/2026-05-29T050000-0500.md
-```
-
-Non-responsibilities:
-
-- No weather logic.
-- No report registry logic.
-- No decision about which prompt to run.
-
-Future note:
-
-- A native LLM client can later replace or supplement this adapter behind a similar interface.
-
-### `internal/forecast`
-
-Core forecast-domain processing.
-
-Responsibilities:
-
-- Define the normalized `Bundle` consumed by report builders.
-- Group hourly forecast data into configured dayparts.
-- Compute derived facts, including:
-  - Temperature ranges.
-  - Apparent-temperature ranges, if available.
-  - Max precipitation probability.
-  - Peak wind and wind gusts.
-  - Precipitation windows.
-  - Thunder mentions.
-  - Snow/ice/freezing risk indicators.
-  - Alert overlap with relevant periods.
-- Select forecast elements relevant to a report period.
-- Provide threshold helpers for impact detection.
-
-Non-responsibilities:
-
-- No CLI behavior.
-- No external API calls.
-- No rendered prose.
-- No direct `scriptorium` calls.
-
-### `internal/report`
-
-Report definitions, registry, period resolution, and report-level contracts.
-
-Responsibilities:
-
-- Define report IDs and report definition contracts.
-- Register report types and variants.
-- Resolve valid periods for each report.
-- Associate report types with prompt IDs.
-- Define comparison strategies and output naming behavior.
-
-Suggested report definitions:
-
-```text
-daily_today       -> prompt weather.daily_report
-daily_tomorrow    -> prompt weather.daily_report
-three_day         -> prompt weather.three_day_outlook
-weekend           -> prompt weather.weekend_outlook
-storm             -> prompt weather.storm_report
-```
-
-`weather.daily_report` should be the standard prompt for one local civil day, regardless of whether that day is today or tomorrow.
-
-A report definition should describe:
-
-- Report ID.
-- Human-readable name.
-- Prompt ID.
-- Valid-period resolver.
-- Briefing builder ID or function.
-- Recent-change comparison strategy.
-- Default output naming pattern.
-- Whether the report participates in morning or evening scheduled batches.
-
-Non-responsibilities:
-
-- No detailed forecast computation.
-- No state storage.
-- No subprocess execution.
-
-### `internal/briefing`
-
-Builds report-specific briefing packages from forecast bundles and report definitions.
-
-Responsibilities:
-
-- Convert a forecast bundle into a report-specific structured briefing package.
-- Keep each report's briefing shape explicit and testable.
-- Attach relevant NWS narrative periods, alerts, forecast discussion context, and weather story context when available.
-- Include metadata such as schema version, configured units/timezone, source warnings, and source provenance.
-- Provide inputs suitable for `scriptorium` data packages.
-
-Report-specific builders should exist for:
-
-- Daily Report.
-- Tomorrow Planning Brief.
-- 3-Day Outlook.
-- Weekend Outlook.
-- Storm Report.
-
-Non-responsibilities:
-
-- No external API fetching.
-- No final prose rendering.
-- No state persistence, except through app orchestration.
-
-Design note:
-
-- This package is the architectural center of the application. A clean briefing package makes `scriptorium` a renderer rather than a source of weather reasoning.
-
-### `internal/changes`
-
-Structured comparison of current and prior briefing snapshots.
-
-Responsibilities:
-
-- Compare current briefing packages against prior comparable snapshots.
-- Apply meaningful-change thresholds.
-- Produce compact structured change summaries for prompt input data packages.
-- Avoid comparison of rendered Markdown report text.
-
-Comparable snapshot matching should be declared by each report definition. Daily Today, Daily Tomorrow, and compatible date slices from multi-day reports may compare by same valid local date when the report registry marks them compatible. Weekend compares by same weekend window. Storm compares by explicit event window.
-
-Meaningful changes may include:
-
-- Temperature changes crossing configured thresholds.
-- Precipitation probability changes by category.
-- Precipitation timing shifts.
-- New, canceled, extended, upgraded, or expanded alerts.
-- Wind gust threshold crossings.
-- Snow/ice/freezing risk changes.
-- Severe-weather wording or risk changes.
-- Confidence or uncertainty changes, if represented in structured briefing data.
-
-Non-responsibilities:
-
-- No fetching prior state directly unless mediated through app/state contracts.
-- No final report prose.
-- No external calls.
-
-### `internal/state`
-
-Durable state store for reports, snapshots, data packages, preflight output, metadata, and comparison lookup.
-
-Responsibilities:
-
-- Persist generated report metadata.
-- Persist briefing snapshots.
-- Persist prompt input data packages.
-- Persist `scriptorium render` preflight output for generated reports.
-- Locate prior comparable snapshots for Recent Changes.
-- Track RunID as generation timestamp plus report ID.
-- Use timestamped managed report names to avoid overwriting prior runs for the same valid period.
-- Use atomic writes where practical.
-- Keep filesystem layout narrow and predictable.
-
-Initial backend:
-
-- Filesystem state.
-
-Potential future backend:
-
-- SQLite or another state database, behind the same store interface.
-
-Suggested state layout:
-
-```text
-workspace/
-  snapshots/
-    daily/
-      2026-05-30/
-        2026-05-29T050000-0500.briefing.json
-        2026-05-29T050000-0500.metadata.json
-    three-day/
-    weekend/
-    storm/
-  reports/
-    daily/
-      2026-05-29T050000-0500.md
-    three-day/
-    weekend/
-    storm/
-  data-packages/
-    daily/
-      2026-05-29T050000-0500.data_package.json
-  preflight/
-    daily/
-      2026-05-29T050000-0500.render.json
-```
-
-Non-responsibilities:
-
-- No weather derivation.
-- No report prose generation.
-- No CLI formatting decisions.
-
-### `internal/promptinput`
-
-Builds the final data package passed to `scriptorium`.
-
-Responsibilities:
-
-- Combine report metadata, briefing package, Recent Changes, selected source context, and source warnings into a prompt input document.
-- Validate required data package fields before invoking `scriptorium`.
-- Keep data package schemas explicit enough to test.
-- Write data package files to the workspace when requested by the app layer.
-
-Non-responsibilities:
-
-- No weather API calls.
-- No forecast derivation.
-- No subprocess execution.
-
-### `internal/timeutil`
-
-Time, clock, and period helpers.
-
-Responsibilities:
-
-- Provide an injectable clock for deterministic tests.
-- Resolve local dates using the configured report timezone.
-- Handle daypart spans, including overnight windows.
-- Normalize valid periods.
-- Provide helpers for recurring scheduled batches.
-
-Non-responsibilities:
-
-- No report-specific forecast logic unless delegated by `internal/report`.
-- No external calls.
-
-## Report Types and Valid-Period Identity
-
-Each generated report must be associated with explicit metadata:
-
-- RunID.
-- Report type.
-- Report variant, if applicable.
-- Generation time.
-- Configured report timezone.
-- Valid period start.
-- Valid period end.
-- Source location ID/name when provided by upstream.
-- Source product timestamps and/or SHA-256 hashes.
-- Source warnings.
-- Briefing snapshot path.
-- Prompt input data package path.
-- Preflight output path.
-- Rendered report path.
-
-All valid periods should use the configured local timezone, default `Chicago`, and half-open `[start,end)` intervals.
-
-Initial valid-period rules:
-
-- Daily Today: current local civil day, `[00:00, next 00:00)`.
-- Daily Tomorrow: next local civil day.
-- 3-Day Outlook: generation time through local midnight after the second following local civil day.
-- Weekend Outlook: Monday through Thursday covers Saturday 00:00 to Monday 00:00; Friday and Saturday cover `max(generation time, Friday 18:00)` to Monday 00:00; scheduled Sunday morning skips Weekend Outlook.
-- Manual Storm Report: requires explicit `--start` and `--end`; accept `YYYY-MM-DDTHH:MM` interpreted in the configured timezone and RFC3339 timestamps with explicit offsets.
-
-The valid period should identify what weather period the report covers, independent of when the report was generated.
-
-Examples:
-
-- A 5 PM Tomorrow Planning Brief for Saturday and a 5 AM Saturday Daily Report both cover the same valid date.
-- A Saturday Weekend Outlook covers the remaining weekend, while a Friday Weekend Outlook may cover Friday evening through Sunday night.
-- A Storm Report covers an explicit forecast event window, not a fixed calendar day.
-
-This identity is required for reliable Recent Changes behavior.
-
-## Scheduled Batch Semantics
-
-The app should support scheduled batches but should not need to be a daemon in the initial version.
-
-Suggested batches:
-
-```text
-morning:
-  - daily_today
-  - three_day
-  - weekend, except Sunday
-
-evening:
-  - daily_tomorrow
-```
-
-Scheduled batches should continue independent reports after a report failure. The CLI should return nonzero if any report failed and should emit an aggregate run summary.
-
-External scheduling should be handled by systemd timers, cron, or another orchestrator. `weatherreporter` should simply provide deterministic commands that can be scheduled.
-
-## Storm Report Direction
-
-The initial version should support manual Storm Report generation:
-
-```text
-weatherreporter generate storm --start 2026-05-29T18:00 --end 2026-05-30T06:00
-```
-
-Future storm monitoring should use a staged design:
-
-```text
-incoming weather data
-    -> deterministic candidate detector
-    -> LLM event evaluator
-    -> storm lifecycle state
-    -> storm report generation or skip decision
-```
-
-Potential storm lifecycle states:
-
-```text
-none -> monitoring -> active_report -> escalated -> deescalating -> resolved
-```
-
-This future behavior should not be built before the core scheduled reports are stable, but the package layout should leave room for it.
-
-## Testing Expectations
-
-Core tests should not require real external services.
-
-Priority test areas:
-
-- Configuration loading and validation, including defaults for `units=us`, `tz=Chicago`, and missing-source policy `warn`.
-- Standard-library CLI command parsing, including `--units`, `--tz`, and storm `--start`/`--end`.
-- Weather API fan-out, source provenance, `data:null`, and missing-source policy behavior.
-- Daypart grouping, especially overnight periods.
-- Valid-period resolution for each report type.
-- Briefing package construction from fixtures.
-- Recent Changes threshold behavior and compatible snapshot matching.
-- Prior snapshot lookup.
-- `scriptorium` adapter behavior using a fake executable or command runner, including both `render` and `run` with `--input data_package=<path>`.
-- Batch partial-failure behavior and aggregate exit status.
-
-## Design Invariants
-
-Preserve these invariants as the project evolves:
-
-- Weather facts come from normalized source data, not from the LLM.
-- The LLM receives curated briefing packages, not unbounded raw weather payloads.
-- Recent Changes are based on structured snapshot comparison, not Markdown diffing.
-- Report types are registered or otherwise centrally defined.
-- External integrations are thin adapters.
-- CLI code wires workflows but does not own domain logic.
-- The first durable state backend is filesystem-based and inspectable.
-- `scriptorium` is an adapter boundary, not an application dependency that leaks across packages.
+Non-roadmap docs must describe implemented behavior only.

docs/roadmap/future.md

@@ -0,0 +1,148 @@
+# Future Roadmap
+
+This roadmap contains project work that is not implemented. Current behavior is
+documented outside `docs/roadmap/`.
+
+## Automatic Storm Monitoring
+
+Manual Storm Report generation is implemented through
+`weatherreporter generate storm --start TIME --end TIME`. Automatic storm-event
+evaluation remains deferred.
+
+Proposed direction:
+
+1. detect candidate events deterministically from alerts, forecast discussion,
+   weather story context, hourly thresholds, and material forecast changes;
+2. evaluate candidates through Scriptorium or another narrow evaluator adapter;
+3. persist storm lifecycle state;
+4. generate or update Storm Reports only when a meaningful event is present;
+5. suppress ordinary low-impact thunder or rain chances.
+
+Possible lifecycle states:
+
+- `none`
+- `monitoring`
+- `active_report`
+- `escalated`
+- `deescalating`
+- `resolved`
+
+Acceptance criteria before implementation:
+
+- scheduled reports and manual Storm Reports remain stable;
+- candidate detection has fixture coverage;
+- evaluator failures are inspectable and do not create noisy report output;
+- manual Storm Report generation remains available.
+
+## Future Report Types And Modules
+
+The module-based prompt package architecture is implemented. Future work should
+add only modules backed by implemented upstream facts and clear report needs.
+
+Possible future report types:
+
+- `next_6_hours` or another short-fuse planning report;
+- event-specific reports with stable event IDs;
+- storm review or yesterday-style reports using historical observations;
+- archive-focused report variants if generated report history becomes a
+  first-class product.
+
+Possible future modules:
+
+- `hourly_table` for compact valid-period hourly facts;
+- `forecast_delta` if a separate stanza is useful beyond current Recent
+  Changes;
+- `weekend_planning` if weekend-specific planning guidance needs a dedicated
+  deterministic stanza;
+- `storm_window_summary` if manual or automatic Storm Reports need a dedicated
+  prompt-facing storm-window module;
+- separate AFD section aliases, such as `afd_key_messages`,
+  `afd_short_term_text`, and `afd_long_term_text`, if separate stanzas prove
+  more useful than `area_forecast_discussion.options.sections`;
+- SPC, radar, QPF, snow/rain total, or historical-observation modules once
+  upstream sources and report requirements exist.
+
+QPF fields such as `measurable_qpf_total_in` and `max_hourly_qpf_in` should
+remain omitted until a real upstream quantitative precipitation source is
+represented in `CollectedFacts`.
+
+Future module work should preserve these boundaries:
+
+- collect upstream facts once per report run;
+- keep upstream fetching out of modules;
+- keep broad reusable calculations in `DerivedFacts`;
+- keep prompt-facing field shape inside module builders;
+- use typed options for configurable module behavior;
+- keep module snapshots structured and deterministic for Recent Changes.
+
+## Distributor Notification Enhancements
+
+Distributor notification currently uploads one managed Markdown report per
+successful generated report through the configured HTTP upload pipeline.
+
+These enhancements are not current behavior:
+
+- `failure_policy: warn`;
+- uploading metadata, module snapshots, data packages, or preflight artifacts;
+- polling distributor status after upload acceptance;
+- durable upload retry queues;
+- distributor-specific CLI flags;
+- making distributor scan the weatherreporter workspace;
+- handling destination routing, Markdown-to-HTML transformation, public URLs,
+  or nginx layout inside weatherreporter.
+
+Any distributor enhancement should preserve the existing adapter boundary:
+weatherreporter selects explicit generated files and submits source bundles,
+while distributor owns destination routing and publication behavior.
+
+## Alternate Runtime Integrations
+
+These ideas are not current behavior:
+
+- native LLM client inside `weatherreporter`;
+- database-backed state;
+- public HTTP API;
+- multi-location selection;
+- daemon mode;
+- multi-user authorization;
+- plugin system;
+- dynamic module loading;
+- user-defined module code;
+- YAML-defined module schemas;
+- module-owned Weather API fetching.
+
+Each item needs its own design note before implementation. Non-roadmap docs
+must not describe these as available behavior.
+
+## Cleanup Refactors
+
+The initial cleanup pass intentionally left these refactors out because the
+current implementation does not yet make them worth the added abstraction.
+
+Revisit these only when new source types, report types, operational
+requirements, or recurring maintenance costs make the duplication materially
+more expensive:
+
+- Weather API optional-source specification/helper refactor: consider when
+  additional Weather API sources make per-source fan-out, policy handling, and
+  provenance wiring repetitive enough to obscure adapter behavior.
+- Broad briefing weather-signal consolidation: consider when multiple module
+  builders repeatedly derive the same weather signals and tests begin to need
+  coordinated fixture updates.
+- Generic workflow engine: defer unless generation, inspection, recovery, or
+  future background workflows gain enough shared step semantics to justify a
+  declared execution model.
+- Cobra migration: defer while the standard-library CLI remains small,
+  explicit, and covered by parser tests.
+- Manifest, resume, or progress system: defer until operators need resumable
+  runs, checkpoint recovery, or richer audit trails than the current durable
+  artifacts and metadata provide.
+- Global test helper package: defer while package-local helpers keep tests
+  clear; revisit only if setup duplication starts to hide behavior.
+- Logging subsystem: defer until there are recurring operator diagnostics that
+  cannot be handled with current errors, metadata, inspection commands, and
+  artifact output.
+
+Any future implementation should preserve the existing public CLI, artifact
+paths, report identities, module boundaries, and adapter boundaries unless a
+separate roadmap explicitly changes them.

docs/troubleshooting.md

@@ -0,0 +1,340 @@
+# Weatherreporter Troubleshooting
+
+This guide lists recurring failures with likely causes, diagnostics, and safe
+fixes. See [CLI reference](cli.md), [Configuration reference](config.md), and
+[Operations guide](operations.md) for normal usage.
+
+## `weather_api.base_url is required`
+
+Symptom: a generation command fails before fetching weather data.
+
+Likely cause: no Weather API base URL is configured.
+
+Diagnostic:
+
+```sh
+weatherreporter generate daily --config ./config.yml --date 2026-05-29
+```
+
+Safe fix: add `weather_api.base_url` to the config file, or pass the intended
+config path with `--config`.
+
+Relevant docs: [Configuration reference](config.md).
+
+## `weather_api.base_url must be an absolute URL`
+
+Symptom: config loading fails with a base URL validation error.
+
+Likely cause: `weather_api.base_url` is missing a scheme or host.
+
+Diagnostic: inspect the configured value in the file passed to `--config`.
+
+Safe fix: use an absolute URL such as `https://weather.api.example.com/`.
+
+Relevant docs: [Configuration reference](config.md).
+
+## Invalid Timezone
+
+Symptom: config loading fails with `weather_api.timezone` context, or a CLI
+timezone override fails.
+
+Likely cause: `weather_api.timezone` or `--tz` is not recognized.
+
+Diagnostic:
+
+```sh
+weatherreporter generate daily --tz America/Chicago --date 2026-05-29
+```
+
+Safe fix: use an accepted timezone value, such as an IANA timezone name,
+`Chicago`, `Stl`, a US timezone abbreviation, or a UTC offset.
+
+Relevant docs: [Configuration reference](config.md).
+
+## Storm Command Rejects Time Bounds
+
+Symptom: `generate storm` fails with `requires --start`, `requires --end`, or
+`requires --end after --start`.
+
+Likely cause: the manual event window is missing or invalid.
+
+Diagnostic:
+
+```sh
+weatherreporter generate storm --start 2026-05-29T18:00 --end 2026-05-30T06:00
+```
+
+Safe fix: provide both bounds. Use `YYYY-MM-DDTHH:MM` in the configured
+timezone, or RFC3339 timestamps with explicit offsets.
+
+Relevant docs: [CLI reference](cli.md).
+
+## Weather API Fetch Fails
+
+Symptom: generation fails with `fetch /...`, an HTTP status, or request context.
+
+Likely cause: the configured Weather API endpoint is unreachable, returned a
+non-2xx response, or returned an invalid response envelope.
+
+Diagnostic:
+
+```sh
+weatherreporter generate daily --config ./config.yml --date 2026-05-29
+```
+
+Safe fix: verify `weather_api.base_url`, network access, and the Weather API
+service response. The adapter fetches `/observations`, `/conditions/current`,
+`/forecast/hourly`, `/forecast/narrative`, `/alerts/active`, and `/discussion`.
+
+Relevant docs: [Configuration reference](config.md).
+
+## Hourly Forecast Is Missing
+
+Symptom: generation fails with hourly forecast context, such as missing hourly
+data or an hourly forecast containing no periods.
+
+Likely cause: hourly forecast data is required for generated reports.
+
+Diagnostic: check the Weather API response for `/forecast/hourly`.
+
+Safe fix: restore hourly forecast data at the Weather API. Missing-source
+policy cannot make hourly optional.
+
+Relevant docs: [Configuration reference](config.md), [Operations guide](operations.md).
+
+## Source Warnings Appear
+
+Symptom: generation succeeds, but metadata or `inspect sources` shows source
+warnings.
+
+Likely cause: an optional source was missing or malformed under a warning
+missing-source policy.
+
+Diagnostic:
+
+```sh
+weatherreporter inspect sources RUN_ID
+weatherreporter inspect metadata RUN_ID
+```
+
+Safe fix: inspect the warning `source`, `code`, `message`, and `endpoint`. Fix
+the upstream optional source, or intentionally change the relevant
+`missing_source` policy.
+
+Relevant docs: [Configuration reference](config.md), [Operations guide](operations.md).
+
+## `scriptorium` Is Not Found Or Cannot Start
+
+Symptom: generation fails with `run scriptorium render` or `run scriptorium`
+and an executable or OS error.
+
+Likely cause: the configured Scriptorium binary is unavailable or not
+executable.
+
+Diagnostic: check `scriptorium.binary` in config and run the same binary outside
+`weatherreporter`.
+
+Safe fix: install Scriptorium, update `scriptorium.binary`, or fix executable
+permissions.
+
+Relevant docs: [Configuration reference](config.md),
+[Scriptorium integration](integrations/scriptorium.md).
+
+## Render Preflight Fails
+
+Symptom: generation fails with `scriptorium render exited with code ...`.
+
+Likely cause: Scriptorium rejected the prompt, config, profile, or
+`data_package` input before report generation.
+
+Diagnostic:
+
+```sh
+weatherreporter inspect metadata RUN_ID
+weatherreporter inspect data-package RUN_ID
+```
+
+Then read the preflight path from metadata. It contains captured stdout, stderr,
+exit code, and command.
+
+Safe fix: fix the Scriptorium configuration, prompt ID, profile, or data package
+input indicated by stderr.
+
+Relevant docs: [Operations guide](operations.md),
+[Scriptorium integration](integrations/scriptorium.md).
+
+## Scriptorium Run Fails
+
+Symptom: generation fails with `scriptorium run exited with code ...`.
+
+Likely cause: Scriptorium failed during report generation or validation.
+
+Diagnostic:
+
+```sh
+weatherreporter inspect metadata RUN_ID
+weatherreporter inspect data-package RUN_ID
+```
+
+If metadata includes a rendered report path, inspect that report as well. A
+nonzero run can still leave a managed report artifact.
+
+Safe fix: use the captured stderr and data package to fix the Scriptorium
+prompt, profile, model configuration, or validation issue.
+
+Relevant docs: [Operations guide](operations.md),
+[Scriptorium integration](integrations/scriptorium.md).
+
+## Batch Command Returns Nonzero
+
+Symptom: `run morning` or `run evening` returns nonzero.
+
+Likely cause: at least one report in the batch failed.
+
+Diagnostic: inspect stdout for the JSON summary and stderr for compact status
+lines.
+
+Safe fix: use the failed report's artifact paths from the summary, then inspect
+metadata, sources, module snapshot, and data package for that RunID.
+
+Relevant docs: [CLI reference](cli.md), [Operations guide](operations.md).
+
+## Invalid Secrets Directory
+
+Symptom: config loading fails with `read secrets directory`, `secret file`, or
+environment variable name context.
+
+Likely cause: `secrets.directory` points to a missing directory or contains an
+invalid entry. Secret entries must be regular files directly under the
+configured directory, and file basenames must match
+`[A-Za-z_][A-Za-z0-9_]*`.
+
+Diagnostic: list the configured directory and inspect entry names and file
+types. Do not print secret file contents.
+
+Safe fix: create the directory, remove subdirectories or symlinks, fix invalid
+filenames, and ensure the weatherreporter process can read each secret file.
+
+Relevant docs: [Configuration reference](config.md).
+
+## Distributor Token Is Missing
+
+Symptom: notification fails with a message that the distributor token
+environment variable is not set.
+
+Likely cause: `notify.distributor.enabled` is true, but the environment
+variable named by `notify.distributor.token_env` was not populated directly or
+through `secrets.directory`.
+
+Diagnostic: check `notify.distributor.token_env`, then verify a matching secret
+file exists under `secrets.directory` or that the process environment includes
+the variable. Do not print the token value.
+
+Safe fix: create a readable secret file whose basename matches `token_env`, or
+set the environment variable through the service manager.
+
+Relevant docs: [Configuration reference](config.md),
+[Operations guide](operations.md).
+
+## Distributor Upload Conflict
+
+Symptom: notification fails with idempotency conflict context.
+
+Likely cause: the same idempotency key was reused for different bundle content
+within the same distributor token and pipeline. By default the bundle ID is a
+stable report-stream identity and the idempotency key appends RunID.
+
+Diagnostic: inspect the failed batch JSON or stderr line for pipeline, bundle,
+and idempotency context. Compare the configured templates with the report RunID
+and report path.
+
+Also inspect the notification artifact linked from metadata. It records the
+rendered pipeline ID, bundle ID, idempotency key, upload result, distributor run
+status, status error, and raw run report JSON when available.
+
+Safe fix: keep idempotency templates stable for retries of the same generated
+report, but do not reuse the same rendered key for different generated report
+content.
+
+Relevant docs: [Operations guide](operations.md),
+[Distributor adapter internals](internal/distributor-adapter.md).
+
+## Distributor Upload Rejected
+
+Symptom: notification fails with distributor upload rejection, HTTP status, or
+bundle validation context.
+
+Likely cause: the distributor endpoint rejected the token, pipeline ID, bundle
+ID, idempotency key, source file, or one of the rendered bundle paths.
+
+Diagnostic: inspect stdout JSON or stderr status lines for
+`notificationError`. Confirm `notify.distributor.endpoint`,
+`notify.distributor.pipeline_id_template`,
+`notify.distributor.report_path_templates`, and token configuration. Token
+values are redacted from weatherreporter errors.
+
+If the upload was accepted but destination output did not change, inspect the
+notification artifact's `runStatus.report`. Distributor actions such as
+`replace_older`, `skip_same`, `skip_destination_newer`, or `failed` explain how
+the destination handled the uploaded bundle.
+
+Safe fix: fix the endpoint, token, templates, or distributor-side upload
+configuration. The weatherreporter upload source is the managed Markdown report,
+not `--out` or `--out-dir` copies.
+
+Relevant docs: [Configuration reference](config.md),
+[Operations guide](operations.md),
+[Distributor adapter internals](internal/distributor-adapter.md).
+
+## Distributor Unavailable
+
+Symptom: notification fails with network, timeout, or service unavailable
+context.
+
+Likely cause: the configured distributor endpoint is unreachable, slow, or
+temporarily unavailable.
+
+Diagnostic: check network access from the weatherreporter host to
+`notify.distributor.endpoint`. For batch runs, inspect which reports have
+`notificationStatus: "failed"`.
+
+Safe fix: restore distributor service availability and rerun the affected
+report or batch. Stable idempotency keys make retrying the same generated report
+safe unless the distributor reports a conflict.
+
+Relevant docs: [Operations guide](operations.md).
+
+## Unknown RunID
+
+Symptom: an inspect command fails with `metadata for run id ... was not found`.
+
+Likely cause: the RunID is mistyped or the command is reading a different
+workspace.
+
+Diagnostic:
+
+```sh
+weatherreporter inspect reports --config ./config.yml --limit 20
+```
+
+Safe fix: copy a RunID from `inspect reports`, or use the same `--config` and
+workspace that generated the report.
+
+Relevant docs: [Operations guide](operations.md).
+
+## Workspace Path Error
+
+Symptom: startup or inspection fails with workspace path validation or
+filesystem read/write context.
+
+Likely cause: a workspace subdirectory is absolute, escapes `workspace.root`, or
+the process cannot read or write the configured path.
+
+Diagnostic: review `workspace.root`, `workspace.snapshots_dir`,
+`workspace.reports_dir`, `workspace.data_packages_dir`, and
+`workspace.preflight_dir`.
+
+Safe fix: keep workspace subdirectories relative to `workspace.root`, and grant
+the process appropriate filesystem permissions.
+
+Relevant docs: [Configuration reference](config.md), [Operations guide](operations.md).

examples/config.yml

@@ -0,0 +1,89 @@
+weather_api:
+  base_url: https://weather.api.rakestrawhome.com/
+  timeout: 15s
+  precision: 1
+  units: us
+  timezone: "America/Chicago"
+  format: json
+
+location:
+  id: home
+  name: Brentwood
+  region: St. Louis Metro
+
+secrets:
+  directory: ""
+
+notify:
+  distributor:
+    enabled: false
+    endpoint: https://distributor.example.com
+    token_env: DISTRIBUTOR_UPLOAD_TOKEN
+    timeout: 30s
+    failure_policy: error
+    pipeline_id_template: "weatherreporter.{artifact_group}"
+    bundle_id_template: "weatherreporter.{location_id}.{report_id}"
+    idempotency_key_template: "{bundle_id}.{run_id}"
+    report_path_templates:
+      - "{valid_start_date}/{artifact_group}/{valid_start_date}-{artifact_group}-{run_id}.md"
+
+missing_source:
+  default: warn
+  sources:
+    alerts: none
+
+scriptorium:
+  binary: scriptorium
+  timeout: 2m
+
+workspace:
+  root: workspace
+  snapshots_dir: snapshots
+  reports_dir: reports
+  data_packages_dir: data-packages
+  preflight_dir: preflight
+  notifications_dir: notifications
+
+dayparts:
+  - name: overnight
+    start: "00:00"
+    end: "06:00"
+  - name: morning
+    start: "06:00"
+    end: "10:00"
+  - name: midday
+    start: "10:00"
+    end: "15:00"
+  - name: afternoon
+    start: "15:00"
+    end: "17:00"
+  - name: evening
+    start: "17:00"
+    end: "24:00"
+
+recent_change:
+  temperature_degrees: 5
+  precip_probability_points: 20
+  wind_gust_miles_per_hour: 10
+  precip_timing_shift_minutes: 120
+
+reports:
+  daily:
+    deterministic_modules:
+      - metadata
+      - current_conditions
+      - narrative_forecast
+      - derived_daily_summary
+      - derived_daypart_summaries
+      - precip_timing
+      - alert_digest
+      - id: area_forecast_discussion
+        options:
+          sections:
+            - product
+            - key_messages
+            - short_term
+            - long_term
+      - weather_story
+      - outdoor_windows
+      - hourly_forecast

examples/minimal-config.yml

@@ -0,0 +1,2 @@
+weather_api:
+  base_url: https://weather.api.example.com/

go.mod

@@ -0,0 +1,7 @@
+module gitea.maximumdirect.net/eric/weatherreporter
+
+go 1.26
+
+require gopkg.in/yaml.v3 v3.0.1
+
+require gitea.maximumdirect.net/eric/distributor v0.5.0

go.sum

@@ -0,0 +1,52 @@
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internal/adapters/distributor/client.go

@@ -0,0 +1,371 @@
+// Package distributor adapts weatherreporter report artifacts to distributor uploads.
+package distributor
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+
+	distributorbundle "gitea.maximumdirect.net/eric/distributor/pkg/bundle"
+	distributorupload "gitea.maximumdirect.net/eric/distributor/pkg/upload"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+)
+
+type Client struct {
+	Endpoint        string
+	TokenEnv        string
+	Timeout         time.Duration
+	newUploadClient uploadClientFactory
+}
+
+type UploadRequest struct {
+	PipelineID     string
+	BundleID       string
+	IdempotencyKey string
+	Files          []UploadFile
+	CreatedAt      time.Time
+}
+
+type UploadFile struct {
+	SourcePath string
+	BundlePath string
+}
+
+type UploadResult struct {
+	RunID        string
+	Status       string
+	UploadStatus string
+	StatusError  string
+	RunStatus    *RunStatus
+}
+
+type RunStatus struct {
+	RunID      string
+	PipelineID string
+	Status     string
+	AcceptedAt time.Time
+	StartedAt  *time.Time
+	FinishedAt *time.Time
+	Report     json.RawMessage
+	Error      string
+}
+
+type IdempotencyConflictError struct {
+	Err error
+}
+
+func (e *IdempotencyConflictError) Error() string {
+	if e == nil || e.Err == nil {
+		return "distributor idempotency conflict"
+	}
+	return e.Err.Error()
+}
+
+func (e *IdempotencyConflictError) Unwrap() error {
+	if e == nil {
+		return nil
+	}
+	return e.Err
+}
+
+type uploadClientFactory func(endpoint, token string, timeout time.Duration) (uploadClient, error)
+
+type uploadClient interface {
+	UploadFiles(ctx context.Context, opts uploadFilesOptions) (uploadFilesResult, error)
+	Status(ctx context.Context, runID string) (runStatus, error)
+}
+
+type uploadFilesOptions struct {
+	PipelineID     string
+	BundleID       string
+	IdempotencyKey string
+	Files          []UploadFile
+	CreatedAt      time.Time
+}
+
+type uploadFilesResult struct {
+	RunID  string
+	Status string
+}
+
+type runStatus struct {
+	RunID      string
+	PipelineID string
+	Status     string
+	AcceptedAt time.Time
+	StartedAt  *time.Time
+	FinishedAt *time.Time
+	Report     json.RawMessage
+	Error      string
+}
+
+const statusPollInterval = 250 * time.Millisecond
+
+func New(cfg config.DistributorNotifyConfig) *Client {
+	return newClient(cfg, newDistributorUploadClient)
+}
+
+func newClient(cfg config.DistributorNotifyConfig, factory uploadClientFactory) *Client {
+	if factory == nil {
+		factory = newDistributorUploadClient
+	}
+	return &Client{
+		Endpoint:        cfg.Endpoint,
+		TokenEnv:        cfg.TokenEnv,
+		Timeout:         cfg.Timeout,
+		newUploadClient: factory,
+	}
+}
+
+func (c *Client) Upload(ctx context.Context, req UploadRequest) (UploadResult, error) {
+	if c == nil {
+		return UploadResult{}, fmt.Errorf("distributor client is nil")
+	}
+	if c.Endpoint == "" {
+		return UploadResult{}, fmt.Errorf("distributor endpoint is required")
+	}
+	if c.TokenEnv == "" {
+		return UploadResult{}, fmt.Errorf("distributor token environment variable is required")
+	}
+	if req.PipelineID == "" {
+		return UploadResult{}, fmt.Errorf("distributor pipeline id is required")
+	}
+	if req.BundleID == "" {
+		return UploadResult{}, fmt.Errorf("distributor bundle id is required")
+	}
+	if req.IdempotencyKey == "" {
+		return UploadResult{}, fmt.Errorf("distributor idempotency key is required for bundle %q", req.BundleID)
+	}
+	if len(req.Files) == 0 {
+		return UploadResult{}, fmt.Errorf("distributor upload files are required for bundle %q", req.BundleID)
+	}
+	for i, file := range req.Files {
+		if file.SourcePath == "" {
+			return UploadResult{}, fmt.Errorf("distributor source path is required for bundle %q file %d", req.BundleID, i)
+		}
+		if file.BundlePath == "" {
+			return UploadResult{}, fmt.Errorf("distributor bundle path is required for bundle %q file %d", req.BundleID, i)
+		}
+	}
+	if c.newUploadClient == nil {
+		return UploadResult{}, fmt.Errorf("distributor upload client factory is required for endpoint %q", c.Endpoint)
+	}
+
+	token := os.Getenv(c.TokenEnv)
+	if token == "" {
+		return UploadResult{}, fmt.Errorf("distributor token environment variable %q is not set", c.TokenEnv)
+	}
+
+	uploadClient, err := c.newUploadClient(c.Endpoint, token, c.Timeout)
+	if err != nil {
+		return UploadResult{}, fmt.Errorf("create distributor upload client for endpoint %q: %w", c.Endpoint, redactToken(err, token))
+	}
+
+	runCtx := ctx
+	if runCtx == nil {
+		runCtx = context.Background()
+	}
+	cancel := func() {}
+	if c.Timeout > 0 {
+		runCtx, cancel = context.WithTimeout(runCtx, c.Timeout)
+	}
+	defer cancel()
+
+	result, err := uploadClient.UploadFiles(runCtx, uploadFilesOptions{
+		PipelineID:     req.PipelineID,
+		BundleID:       req.BundleID,
+		IdempotencyKey: req.IdempotencyKey,
+		Files:          append([]UploadFile(nil), req.Files...),
+		CreatedAt:      req.CreatedAt,
+	})
+	if err != nil {
+		return UploadResult{}, wrapUploadError(err, uploadErrorContext{
+			Endpoint:       c.Endpoint,
+			PipelineID:     req.PipelineID,
+			BundleID:       req.BundleID,
+			IdempotencyKey: req.IdempotencyKey,
+			SourcePaths:    uploadSourcePaths(req.Files),
+			BundlePaths:    uploadBundlePaths(req.Files),
+			Token:          token,
+		})
+	}
+
+	uploadResult := UploadResult{
+		RunID:        result.RunID,
+		Status:       result.Status,
+		UploadStatus: result.Status,
+	}
+	status, statusErr := waitForRunStatus(runCtx, uploadClient, result.RunID, c.Timeout > 0)
+	if status.RunID != "" || status.Status != "" {
+		uploadResult.RunStatus = &RunStatus{
+			RunID:      status.RunID,
+			PipelineID: status.PipelineID,
+			Status:     status.Status,
+			AcceptedAt: status.AcceptedAt,
+			StartedAt:  status.StartedAt,
+			FinishedAt: status.FinishedAt,
+			Report:     append(json.RawMessage(nil), status.Report...),
+			Error:      redactTokenString(status.Error, token),
+		}
+		if status.Status != "" {
+			uploadResult.Status = status.Status
+		}
+	}
+	if statusErr != nil {
+		uploadResult.StatusError = redactTokenString(statusErr.Error(), token)
+		return uploadResult, nil
+	}
+	if status.Status == "failed" {
+		return uploadResult, fmt.Errorf("distributor run %q failed: %s", status.RunID, uploadResult.RunStatus.Error)
+	}
+	return uploadResult, nil
+}
+
+func waitForRunStatus(ctx context.Context, client uploadClient, runID string, poll bool) (runStatus, error) {
+	status, err := client.Status(ctx, runID)
+	if err != nil || terminalRunStatus(status.Status) || !poll {
+		return status, err
+	}
+
+	for {
+		timer := time.NewTimer(statusPollInterval)
+		select {
+		case <-ctx.Done():
+			timer.Stop()
+			return status, fmt.Errorf("distributor run %q did not reach terminal status before timeout: %w", runID, ctx.Err())
+		case <-timer.C:
+		}
+
+		next, err := client.Status(ctx, runID)
+		if err != nil {
+			return status, err
+		}
+		status = next
+		if terminalRunStatus(status.Status) {
+			return status, nil
+		}
+	}
+}
+
+func terminalRunStatus(status string) bool {
+	return status == "succeeded" || status == "failed"
+}
+
+type distributorUploadClient struct {
+	client *distributorupload.Client
+}
+
+func newDistributorUploadClient(endpoint, token string, timeout time.Duration) (uploadClient, error) {
+	httpClient := (*http.Client)(nil)
+	if timeout > 0 {
+		httpClient = &http.Client{Timeout: timeout}
+	}
+	client, err := distributorupload.NewClient(distributorupload.ClientOptions{
+		Endpoint:   endpoint,
+		Token:      token,
+		HTTPClient: httpClient,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return distributorUploadClient{client: client}, nil
+}
+
+func (c distributorUploadClient) UploadFiles(ctx context.Context, opts uploadFilesOptions) (uploadFilesResult, error) {
+	files := make([]distributorbundle.BundleFile, 0, len(opts.Files))
+	for _, file := range opts.Files {
+		files = append(files, distributorbundle.BundleFile{
+			SourcePath: file.SourcePath,
+			Path:       file.BundlePath,
+		})
+	}
+	result, err := c.client.UploadFiles(ctx, distributorupload.UploadFilesOptions{
+		PipelineID:     opts.PipelineID,
+		ID:             opts.BundleID,
+		Created:        opts.CreatedAt,
+		IdempotencyKey: opts.IdempotencyKey,
+		Files:          files,
+	})
+	if err != nil {
+		return uploadFilesResult{}, err
+	}
+	return uploadFilesResult{
+		RunID:  result.RunID,
+		Status: result.Status,
+	}, nil
+}
+
+func (c distributorUploadClient) Status(ctx context.Context, runID string) (runStatus, error) {
+	status, err := c.client.Status(ctx, runID)
+	if err != nil {
+		return runStatus{}, err
+	}
+	return runStatus{
+		RunID:      status.RunID,
+		PipelineID: status.PipelineID,
+		Status:     status.Status,
+		AcceptedAt: status.AcceptedAt,
+		StartedAt:  status.StartedAt,
+		FinishedAt: status.FinishedAt,
+		Report:     append(json.RawMessage(nil), status.Report...),
+		Error:      status.Error,
+	}, nil
+}
+
+type uploadErrorContext struct {
+	Endpoint       string
+	PipelineID     string
+	BundleID       string
+	IdempotencyKey string
+	SourcePaths    []string
+	BundlePaths    []string
+	Token          string
+}
+
+func wrapUploadError(err error, ctx uploadErrorContext) error {
+	var conflict *distributorupload.IdempotencyConflictError
+	isConflict := errors.As(err, &conflict)
+	err = redactToken(err, ctx.Token)
+	if isConflict {
+		return &IdempotencyConflictError{
+			Err: fmt.Errorf("upload distributor bundle %q to pipeline %q at endpoint %q with idempotency key %q from sources %q as bundle paths %q: idempotency conflict: %w", ctx.BundleID, ctx.PipelineID, ctx.Endpoint, ctx.IdempotencyKey, ctx.SourcePaths, ctx.BundlePaths, err),
+		}
+	}
+	return fmt.Errorf("upload distributor bundle %q to pipeline %q at endpoint %q with idempotency key %q from sources %q as bundle paths %q: %w", ctx.BundleID, ctx.PipelineID, ctx.Endpoint, ctx.IdempotencyKey, ctx.SourcePaths, ctx.BundlePaths, err)
+}
+
+func uploadSourcePaths(files []UploadFile) []string {
+	paths := make([]string, 0, len(files))
+	for _, file := range files {
+		paths = append(paths, file.SourcePath)
+	}
+	return paths
+}
+
+func uploadBundlePaths(files []UploadFile) []string {
+	paths := make([]string, 0, len(files))
+	for _, file := range files {
+		paths = append(paths, file.BundlePath)
+	}
+	return paths
+}
+
+func redactToken(err error, token string) error {
+	if err == nil || token == "" {
+		return err
+	}
+	return errors.New(redactTokenString(err.Error(), token))
+}
+
+func redactTokenString(value, token string) string {
+	if token == "" {
+		return value
+	}
+	return strings.ReplaceAll(value, token, "[redacted]")
+}

internal/adapters/distributor/client_test.go

@@ -0,0 +1,406 @@
+package distributor
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	distributorupload "gitea.maximumdirect.net/eric/distributor/pkg/upload"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+)
+
+func TestUploadUsesConfiguredClientAndFiles(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	cfg.TokenEnv = "DISTRIBUTOR_UPLOAD_TOKEN"
+	cfg.Timeout = 15 * time.Second
+	t.Setenv(cfg.TokenEnv, "secret-token")
+
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			result: uploadFilesResult{RunID: "run-123", Status: "accepted"},
+			status: runStatus{RunID: "run-123", PipelineID: "reports", Status: "succeeded", Report: json.RawMessage(`{"actions":[{"action":"replace_older"}]}`)},
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	result, err := client.Upload(context.Background(), UploadRequest{
+		PipelineID:     "weatherreporter.daily",
+		BundleID:       "weatherreporter.home.daily.run",
+		IdempotencyKey: "weatherreporter.home.daily.run",
+		Files: []UploadFile{
+			{SourcePath: "/tmp/report.md", BundlePath: "2026-06-07/daily/report.md"},
+			{SourcePath: "/tmp/report.md", BundlePath: "2026-06-07/daily/latest.md"},
+		},
+		CreatedAt: time.Date(2026, 6, 7, 12, 0, 0, 123, time.UTC),
+	})
+	if err != nil {
+		t.Fatalf("Upload() error = %v", err)
+	}
+	if result.RunID != "run-123" || result.Status != "succeeded" || result.UploadStatus != "accepted" {
+		t.Fatalf("result = %#v, want accepted run", result)
+	}
+	if result.RunStatus == nil || result.RunStatus.PipelineID != "reports" || !strings.Contains(string(result.RunStatus.Report), "replace_older") {
+		t.Fatalf("RunStatus = %#v, want parsed run report", result.RunStatus)
+	}
+	if factory.endpoint != cfg.Endpoint {
+		t.Fatalf("factory endpoint = %q, want %q", factory.endpoint, cfg.Endpoint)
+	}
+	if factory.token != "secret-token" {
+		t.Fatalf("factory token = %q, want secret-token", factory.token)
+	}
+	if factory.timeout != 15*time.Second {
+		t.Fatalf("factory timeout = %s, want 15s", factory.timeout)
+	}
+	got := factory.client.opts
+	if got.PipelineID != "weatherreporter.daily" {
+		t.Fatalf("PipelineID = %q, want weatherreporter.daily", got.PipelineID)
+	}
+	if got.BundleID != "weatherreporter.home.daily.run" {
+		t.Fatalf("BundleID = %q, want weatherreporter.home.daily.run", got.BundleID)
+	}
+	if got.IdempotencyKey != "weatherreporter.home.daily.run" {
+		t.Fatalf("IdempotencyKey = %q, want weatherreporter.home.daily.run", got.IdempotencyKey)
+	}
+	if len(got.Files) != 2 {
+		t.Fatalf("files = %#v, want two mappings", got.Files)
+	}
+	if got.Files[0].SourcePath != "/tmp/report.md" || got.Files[0].BundlePath != "2026-06-07/daily/report.md" {
+		t.Fatalf("first file = %#v, want archive mapping", got.Files[0])
+	}
+	if got.Files[1].SourcePath != "/tmp/report.md" || got.Files[1].BundlePath != "2026-06-07/daily/latest.md" {
+		t.Fatalf("second file = %#v, want latest mapping", got.Files[1])
+	}
+	if got.CreatedAt.IsZero() {
+		t.Fatal("CreatedAt is zero, want generated report timestamp")
+	}
+	if factory.client.statusRunID != "run-123" {
+		t.Fatalf("Status runID = %q, want run-123", factory.client.statusRunID)
+	}
+}
+
+func TestUploadRejectsMissingInputs(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	t.Setenv(cfg.TokenEnv, "secret-token")
+
+	tests := []struct {
+		name    string
+		mutate  func(*Client, *UploadRequest)
+		wantErr string
+	}{
+		{
+			name: "Token",
+			mutate: func(c *Client, req *UploadRequest) {
+				t.Setenv(c.TokenEnv, "")
+			},
+			wantErr: "token environment variable",
+		},
+		{
+			name: "PipelineID",
+			mutate: func(c *Client, req *UploadRequest) {
+				req.PipelineID = ""
+			},
+			wantErr: "pipeline id is required",
+		},
+		{
+			name: "Files",
+			mutate: func(c *Client, req *UploadRequest) {
+				req.Files = nil
+			},
+			wantErr: "upload files are required",
+		},
+		{
+			name: "SourcePath",
+			mutate: func(c *Client, req *UploadRequest) {
+				req.Files[0].SourcePath = ""
+			},
+			wantErr: "source path is required",
+		},
+		{
+			name: "BundlePath",
+			mutate: func(c *Client, req *UploadRequest) {
+				req.Files[0].BundlePath = ""
+			},
+			wantErr: "bundle path is required",
+		},
+		{
+			name: "UploadClientFactory",
+			mutate: func(c *Client, req *UploadRequest) {
+				c.newUploadClient = nil
+			},
+			wantErr: "upload client factory is required",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Setenv(cfg.TokenEnv, "secret-token")
+			client := newClient(cfg, (&fakeUploadFactory{client: &fakeUploadClient{}}).newClient)
+			req := validUploadRequest()
+			tt.mutate(client, &req)
+
+			_, err := client.Upload(context.Background(), req)
+			if err == nil {
+				t.Fatal("Upload() error = nil, want error")
+			}
+			if !strings.Contains(err.Error(), tt.wantErr) {
+				t.Fatalf("error = %q, want %q", err.Error(), tt.wantErr)
+			}
+			if strings.Contains(err.Error(), "secret-token") {
+				t.Fatalf("error = %q, want no token value", err.Error())
+			}
+		})
+	}
+}
+
+func TestUploadWrapsFactoryErrorWithoutToken(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		err: fmt.Errorf("factory failed with secret-token"),
+	}
+	client := newClient(cfg, factory.newClient)
+
+	_, err := client.Upload(context.Background(), validUploadRequest())
+	if err == nil {
+		t.Fatal("Upload() error = nil, want error")
+	}
+	if strings.Contains(err.Error(), "secret-token") {
+		t.Fatalf("error = %q, want no token value", err.Error())
+	}
+	if !strings.Contains(err.Error(), cfg.Endpoint) {
+		t.Fatalf("error = %q, want endpoint context", err.Error())
+	}
+}
+
+func TestUploadWrapsUploadFailureWithContextWithoutToken(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{err: fmt.Errorf("server rejected secret-token")},
+	}
+	client := newClient(cfg, factory.newClient)
+	req := validUploadRequest()
+
+	_, err := client.Upload(context.Background(), req)
+	if err == nil {
+		t.Fatal("Upload() error = nil, want error")
+	}
+	for _, want := range []string{cfg.Endpoint, req.PipelineID, req.BundleID, req.IdempotencyKey, req.Files[0].SourcePath, req.Files[0].BundlePath, req.Files[1].BundlePath} {
+		if !strings.Contains(err.Error(), want) {
+			t.Fatalf("error = %q, want context %q", err.Error(), want)
+		}
+	}
+	if strings.Contains(err.Error(), "secret-token") {
+		t.Fatalf("error = %q, want no token value", err.Error())
+	}
+}
+
+func TestUploadReturnsAcceptedWhenStatusLookupFails(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			result:    uploadFilesResult{RunID: "run-123", Status: "accepted"},
+			statusErr: fmt.Errorf("status rejected secret-token"),
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	result, err := client.Upload(context.Background(), validUploadRequest())
+	if err != nil {
+		t.Fatalf("Upload() error = %v, want accepted upload despite status lookup failure", err)
+	}
+	if result.Status != "accepted" || result.StatusError == "" {
+		t.Fatalf("result = %#v, want accepted status with status error", result)
+	}
+	if strings.Contains(result.StatusError, "secret-token") {
+		t.Fatalf("StatusError = %q, want token redacted", result.StatusError)
+	}
+}
+
+func TestUploadPollsUntilTerminalStatus(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	cfg.Timeout = 2 * time.Second
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			result: uploadFilesResult{RunID: "run-123", Status: "accepted"},
+			statuses: []runStatus{
+				{RunID: "run-123", Status: "accepted"},
+				{RunID: "run-123", Status: "succeeded", Report: json.RawMessage(`{"actions":[{"action":"replace_older"}]}`)},
+			},
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	result, err := client.Upload(context.Background(), validUploadRequest())
+	if err != nil {
+		t.Fatalf("Upload() error = %v", err)
+	}
+	if result.Status != "succeeded" || result.RunStatus == nil || !strings.Contains(string(result.RunStatus.Report), "replace_older") {
+		t.Fatalf("result = %#v, want terminal succeeded status with run report", result)
+	}
+	if factory.client.statusCalls != 2 {
+		t.Fatalf("status calls = %d, want 2", factory.client.statusCalls)
+	}
+}
+
+func TestUploadReturnsLatestStatusWhenPollingTimesOut(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	cfg.Timeout = time.Millisecond
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			result: uploadFilesResult{RunID: "run-123", Status: "accepted"},
+			status: runStatus{RunID: "run-123", Status: "running"},
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	result, err := client.Upload(context.Background(), validUploadRequest())
+	if err != nil {
+		t.Fatalf("Upload() error = %v, want accepted upload with status timeout recorded", err)
+	}
+	if result.Status != "running" || result.StatusError == "" {
+		t.Fatalf("result = %#v, want latest status and status timeout", result)
+	}
+}
+
+func TestUploadFailsWhenDistributorRunFailed(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			result: uploadFilesResult{RunID: "run-123", Status: "accepted"},
+			status: runStatus{
+				RunID:  "run-123",
+				Status: "failed",
+				Error:  "destination rejected secret-token",
+				Report: json.RawMessage(`{"actions":[{"action":"failed"}]}`),
+			},
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	result, err := client.Upload(context.Background(), validUploadRequest())
+	if err == nil {
+		t.Fatal("Upload() error = nil, want failed distributor run error")
+	}
+	if result.RunStatus == nil || result.RunStatus.Status != "failed" || !strings.Contains(string(result.RunStatus.Report), "failed") {
+		t.Fatalf("result = %#v, want failed run status report", result)
+	}
+	if strings.Contains(err.Error(), "secret-token") || strings.Contains(result.RunStatus.Error, "secret-token") {
+		t.Fatalf("error/result leaked token: err=%q result=%#v", err.Error(), result)
+	}
+}
+
+func TestUploadPreservesIdempotencyConflictDiagnosis(t *testing.T) {
+	cfg := config.Defaults().Notify.Distributor
+	cfg.Endpoint = "https://distributor.example.test"
+	t.Setenv(cfg.TokenEnv, "secret-token")
+	factory := &fakeUploadFactory{
+		client: &fakeUploadClient{
+			err: &distributorupload.IdempotencyConflictError{
+				HTTPError: distributorupload.HTTPError{
+					StatusCode: 409,
+					Status:     "409 Conflict",
+					Message:    "conflicting upload for secret-token",
+				},
+			},
+		},
+	}
+	client := newClient(cfg, factory.newClient)
+
+	_, err := client.Upload(context.Background(), validUploadRequest())
+	if err == nil {
+		t.Fatal("Upload() error = nil, want error")
+	}
+	var conflict *IdempotencyConflictError
+	if !errors.As(err, &conflict) {
+		t.Fatalf("Upload() error = %T %v, want IdempotencyConflictError", err, err)
+	}
+	if !strings.Contains(err.Error(), "idempotency conflict") {
+		t.Fatalf("error = %q, want idempotency conflict diagnosis", err.Error())
+	}
+	if strings.Contains(err.Error(), "secret-token") {
+		t.Fatalf("error = %q, want no token value", err.Error())
+	}
+}
+
+func validUploadRequest() UploadRequest {
+	return UploadRequest{
+		PipelineID:     "weatherreporter.daily",
+		BundleID:       "weatherreporter.home.daily.run",
+		IdempotencyKey: "weatherreporter.home.daily.run",
+		Files: []UploadFile{
+			{SourcePath: "/tmp/report.md", BundlePath: "2026-06-07/daily/report.md"},
+			{SourcePath: "/tmp/report.md", BundlePath: "2026-06-07/daily/latest.md"},
+		},
+		CreatedAt: time.Date(2026, 6, 7, 12, 0, 0, 123, time.UTC),
+	}
+}
+
+type fakeUploadFactory struct {
+	endpoint string
+	token    string
+	timeout  time.Duration
+	client   *fakeUploadClient
+	err      error
+}
+
+func (f *fakeUploadFactory) newClient(endpoint, token string, timeout time.Duration) (uploadClient, error) {
+	f.endpoint = endpoint
+	f.token = token
+	f.timeout = timeout
+	if f.err != nil {
+		return nil, f.err
+	}
+	return f.client, nil
+}
+
+type fakeUploadClient struct {
+	opts        uploadFilesOptions
+	statusRunID string
+	statusCalls int
+	result      uploadFilesResult
+	status      runStatus
+	statuses    []runStatus
+	err         error
+	statusErr   error
+}
+
+func (c *fakeUploadClient) UploadFiles(ctx context.Context, opts uploadFilesOptions) (uploadFilesResult, error) {
+	c.opts = opts
+	if c.err != nil {
+		return uploadFilesResult{}, c.err
+	}
+	return c.result, nil
+}
+
+func (c *fakeUploadClient) Status(ctx context.Context, runID string) (runStatus, error) {
+	c.statusRunID = runID
+	c.statusCalls++
+	if c.statusErr != nil {
+		return runStatus{}, c.statusErr
+	}
+	if len(c.statuses) > 0 {
+		index := c.statusCalls - 1
+		if index >= len(c.statuses) {
+			index = len(c.statuses) - 1
+		}
+		return c.statuses[index], nil
+	}
+	return c.status, nil
+}

internal/adapters/scriptorium/runner.go

@@ -0,0 +1,248 @@
+// Package scriptorium adapts the external scriptorium CLI.
+package scriptorium
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os/exec"
+	"time"
+)
+
+const maxCapturedOutputBytes = 1024 * 1024
+
+type CommandRunner interface {
+	Run(ctx context.Context, name string, args []string, timeout time.Duration) (CommandResult, error)
+}
+
+type CommandResult struct {
+	Stdout          []byte
+	Stderr          []byte
+	StdoutTruncated bool
+	StderrTruncated bool
+	ExitCode        int
+}
+
+type ExecRunner struct{}
+
+func (ExecRunner) Run(ctx context.Context, name string, args []string, timeout time.Duration) (CommandResult, error) {
+	runCtx := ctx
+	cancel := func() {}
+	if timeout > 0 {
+		runCtx, cancel = context.WithTimeout(ctx, timeout)
+	}
+	defer cancel()
+
+	cmd := exec.CommandContext(runCtx, name, args...)
+	stdout := &limitedBuffer{limit: maxCapturedOutputBytes}
+	stderr := &limitedBuffer{limit: maxCapturedOutputBytes}
+	cmd.Stdout = stdout
+	cmd.Stderr = stderr
+	err := cmd.Run()
+	result := CommandResult{
+		Stdout:          stdout.Bytes(),
+		Stderr:          stderr.Bytes(),
+		StdoutTruncated: stdout.Truncated(),
+		StderrTruncated: stderr.Truncated(),
+		ExitCode:        0,
+	}
+	if err == nil {
+		return result, nil
+	}
+	if runCtx.Err() != nil {
+		return result, runCtx.Err()
+	}
+	if exitErr, ok := err.(*exec.ExitError); ok {
+		result.ExitCode = exitErr.ExitCode()
+		return result, nil
+	}
+	return result, err
+}
+
+type Runner struct {
+	Binary     string
+	ConfigPath string
+	Profile    string
+	Timeout    time.Duration
+	ExtraArgs  []string
+	Commands   CommandRunner
+}
+
+type RenderRequest struct {
+	PromptID        string
+	DataPackagePath string
+}
+
+type RunRequest struct {
+	PromptID        string
+	DataPackagePath string
+	OutputPath      string
+}
+
+type RenderResult struct {
+	Command         []string `json:"command"`
+	Stdout          string   `json:"stdout"`
+	Stderr          string   `json:"stderr"`
+	StdoutTruncated bool     `json:"stdoutTruncated,omitempty"`
+	StderrTruncated bool     `json:"stderrTruncated,omitempty"`
+	ExitCode        int      `json:"exitCode"`
+}
+
+type RunResult struct {
+	Command         []string `json:"command"`
+	Stdout          string   `json:"stdout"`
+	Stderr          string   `json:"stderr"`
+	StdoutTruncated bool     `json:"stdoutTruncated,omitempty"`
+	StderrTruncated bool     `json:"stderrTruncated,omitempty"`
+	ExitCode        int      `json:"exitCode"`
+	OutputPath      string   `json:"outputPath"`
+}
+
+func (r Runner) Render(ctx context.Context, req RenderRequest) (*RenderResult, error) {
+	if req.PromptID == "" {
+		return nil, fmt.Errorf("prompt id is required")
+	}
+	if req.DataPackagePath == "" {
+		return nil, fmt.Errorf("data package path is required")
+	}
+	execution, err := r.execute(ctx, r.renderArgs(req))
+	if err != nil {
+		return nil, fmt.Errorf("run scriptorium render: %w", err)
+	}
+	result := &RenderResult{
+		Command:         execution.argv(),
+		Stdout:          string(execution.result.Stdout),
+		Stderr:          string(execution.result.Stderr),
+		StdoutTruncated: execution.result.StdoutTruncated,
+		StderrTruncated: execution.result.StderrTruncated,
+		ExitCode:        execution.result.ExitCode,
+	}
+	if execution.result.ExitCode != 0 {
+		return result, fmt.Errorf("scriptorium render exited with code %d: %s", execution.result.ExitCode, result.Stderr)
+	}
+	return result, nil
+}
+
+func (r Runner) Run(ctx context.Context, req RunRequest) (*RunResult, error) {
+	if req.PromptID == "" {
+		return nil, fmt.Errorf("prompt id is required")
+	}
+	if req.DataPackagePath == "" {
+		return nil, fmt.Errorf("data package path is required")
+	}
+	if req.OutputPath == "" {
+		return nil, fmt.Errorf("output path is required")
+	}
+	execution, err := r.execute(ctx, r.runArgs(req))
+	if err != nil {
+		return nil, fmt.Errorf("run scriptorium: %w", err)
+	}
+	result := &RunResult{
+		Command:         execution.argv(),
+		Stdout:          string(execution.result.Stdout),
+		Stderr:          string(execution.result.Stderr),
+		StdoutTruncated: execution.result.StdoutTruncated,
+		StderrTruncated: execution.result.StderrTruncated,
+		ExitCode:        execution.result.ExitCode,
+		OutputPath:      req.OutputPath,
+	}
+	if execution.result.ExitCode != 0 {
+		return result, fmt.Errorf("scriptorium run exited with code %d: %s", execution.result.ExitCode, result.Stderr)
+	}
+	return result, nil
+}
+
+type execution struct {
+	binary string
+	args   []string
+	result CommandResult
+}
+
+func (r Runner) execute(ctx context.Context, args []string) (execution, error) {
+	binary := r.Binary
+	if binary == "" {
+		binary = "scriptorium"
+	}
+	commands := r.Commands
+	if commands == nil {
+		commands = ExecRunner{}
+	}
+	result, err := commands.Run(ctx, binary, args, r.Timeout)
+	if err != nil {
+		return execution{}, err
+	}
+	return execution{binary: binary, args: args, result: result}, nil
+}
+
+func (e execution) argv() []string {
+	return append([]string{e.binary}, e.args...)
+}
+
+func (r Runner) renderArgs(req RenderRequest) []string {
+	args := []string{"render"}
+	if r.ConfigPath != "" {
+		args = append(args, "--config", r.ConfigPath)
+	}
+	if r.Profile != "" {
+		args = append(args, "--profile", r.Profile)
+	}
+	args = append(args,
+		"--prompt", req.PromptID,
+		"--input", "data_package="+req.DataPackagePath,
+		"--format", "json",
+	)
+	args = append(args, r.ExtraArgs...)
+	return args
+}
+
+func (r Runner) runArgs(req RunRequest) []string {
+	args := []string{"run"}
+	if r.ConfigPath != "" {
+		args = append(args, "--config", r.ConfigPath)
+	}
+	if r.Profile != "" {
+		args = append(args, "--profile", r.Profile)
+	}
+	args = append(args,
+		"--prompt", req.PromptID,
+		"--input", "data_package="+req.DataPackagePath,
+		"--out", req.OutputPath,
+	)
+	args = append(args, r.ExtraArgs...)
+	return args
+}
+
+type limitedBuffer struct {
+	data      []byte
+	limit     int
+	truncated bool
+}
+
+func (b *limitedBuffer) Write(p []byte) (int, error) {
+	if b.limit <= 0 {
+		b.truncated = true
+		return len(p), nil
+	}
+	remaining := b.limit - len(b.data)
+	if remaining <= 0 {
+		b.truncated = true
+		return len(p), nil
+	}
+	if len(p) > remaining {
+		b.data = append(b.data, p[:remaining]...)
+		b.truncated = true
+		return len(p), nil
+	}
+	b.data = append(b.data, p...)
+	return len(p), nil
+}
+
+func (b *limitedBuffer) Bytes() []byte {
+	return append([]byte{}, b.data...)
+}
+
+func (b *limitedBuffer) Truncated() bool {
+	return b.truncated
+}
+
+var _ io.Writer = (*limitedBuffer)(nil)

internal/adapters/scriptorium/runner_test.go

@@ -0,0 +1,163 @@
+package scriptorium
+
+import (
+	"context"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestRenderConstructsCommand(t *testing.T) {
+	commands := &fakeCommands{result: CommandResult{Stdout: []byte(`{"ok":true}`)}}
+	runner := Runner{
+		Binary:     "/usr/local/bin/scriptorium",
+		ConfigPath: "/etc/scriptorium.yml",
+		Profile:    "weather",
+		Timeout:    time.Minute,
+		Commands:   commands,
+	}
+
+	result, err := runner.Render(context.Background(), RenderRequest{
+		PromptID:        "weather.daily_report",
+		DataPackagePath: "/tmp/data_package.yaml",
+	})
+	if err != nil {
+		t.Fatalf("Render() error = %v", err)
+	}
+
+	wantArgs := []string{
+		"render",
+		"--config", "/etc/scriptorium.yml",
+		"--profile", "weather",
+		"--prompt", "weather.daily_report",
+		"--input", "data_package=/tmp/data_package.yaml",
+		"--format", "json",
+	}
+	if commands.name != "/usr/local/bin/scriptorium" {
+		t.Fatalf("command name = %q, want custom binary", commands.name)
+	}
+	if !reflect.DeepEqual(commands.args, wantArgs) {
+		t.Fatalf("args = %#v, want %#v", commands.args, wantArgs)
+	}
+	if !reflect.DeepEqual(result.Command, append([]string{"/usr/local/bin/scriptorium"}, wantArgs...)) {
+		t.Fatalf("result command = %#v, want full argv", result.Command)
+	}
+}
+
+func TestRenderReturnsResultForNonzeroExit(t *testing.T) {
+	runner := Runner{
+		Commands: &fakeCommands{
+			result: CommandResult{
+				Stderr:   []byte("missing input"),
+				ExitCode: 1,
+			},
+		},
+	}
+
+	result, err := runner.Render(context.Background(), RenderRequest{
+		PromptID:        "weather.daily_report",
+		DataPackagePath: "/tmp/data_package.yaml",
+	})
+	if err == nil {
+		t.Fatal("Render() error = nil, want nonzero exit error")
+	}
+	if result == nil {
+		t.Fatal("Render() result = nil, want captured result")
+	}
+	if result.ExitCode != 1 {
+		t.Fatalf("ExitCode = %d, want 1", result.ExitCode)
+	}
+	if !strings.Contains(err.Error(), "missing input") {
+		t.Fatalf("error = %q, want stderr context", err.Error())
+	}
+}
+
+func TestRunConstructsCommand(t *testing.T) {
+	commands := &fakeCommands{result: CommandResult{Stderr: []byte("wrote report")}}
+	runner := Runner{
+		Binary:     "/usr/local/bin/scriptorium",
+		ConfigPath: "/etc/scriptorium.yml",
+		Profile:    "weather",
+		Timeout:    45 * time.Second,
+		Commands:   commands,
+	}
+
+	result, err := runner.Run(context.Background(), RunRequest{
+		PromptID:        "weather.daily_report",
+		DataPackagePath: "/tmp/data_package.yaml",
+		OutputPath:      "/tmp/daily.md",
+	})
+	if err != nil {
+		t.Fatalf("Run() error = %v", err)
+	}
+
+	wantArgs := []string{
+		"run",
+		"--config", "/etc/scriptorium.yml",
+		"--profile", "weather",
+		"--prompt", "weather.daily_report",
+		"--input", "data_package=/tmp/data_package.yaml",
+		"--out", "/tmp/daily.md",
+	}
+	if commands.name != "/usr/local/bin/scriptorium" {
+		t.Fatalf("command name = %q, want custom binary", commands.name)
+	}
+	if !reflect.DeepEqual(commands.args, wantArgs) {
+		t.Fatalf("args = %#v, want %#v", commands.args, wantArgs)
+	}
+	if commands.timeout != 45*time.Second {
+		t.Fatalf("timeout = %s, want 45s", commands.timeout)
+	}
+	if !reflect.DeepEqual(result.Command, append([]string{"/usr/local/bin/scriptorium"}, wantArgs...)) {
+		t.Fatalf("result command = %#v, want full argv", result.Command)
+	}
+	if result.OutputPath != "/tmp/daily.md" {
+		t.Fatalf("OutputPath = %q, want /tmp/daily.md", result.OutputPath)
+	}
+}
+
+func TestRunReturnsResultForValidationExit(t *testing.T) {
+	runner := Runner{
+		Commands: &fakeCommands{
+			result: CommandResult{
+				Stdout:   []byte("# Daily Report\n"),
+				Stderr:   []byte("validation failed"),
+				ExitCode: 2,
+			},
+		},
+	}
+
+	result, err := runner.Run(context.Background(), RunRequest{
+		PromptID:        "weather.daily_report",
+		DataPackagePath: "/tmp/data_package.yaml",
+		OutputPath:      "/tmp/daily.md",
+	})
+	if err == nil {
+		t.Fatal("Run() error = nil, want nonzero exit error")
+	}
+	if result == nil {
+		t.Fatal("Run() result = nil, want captured result")
+	}
+	if result.ExitCode != 2 {
+		t.Fatalf("ExitCode = %d, want 2", result.ExitCode)
+	}
+	if !strings.Contains(err.Error(), "validation failed") {
+		t.Fatalf("error = %q, want stderr context", err.Error())
+	}
+}
+
+type fakeCommands struct {
+	name    string
+	args    []string
+	timeout time.Duration
+	result  CommandResult
+	err     error
+}
+
+func (f *fakeCommands) Run(_ context.Context, name string, args []string, timeout time.Duration) (CommandResult, error) {
+	f.name = name
+	f.args = append([]string{}, args...)
+	f.timeout = timeout
+	return f.result, f.err
+}

internal/adapters/weatherapi/client.go

@@ -0,0 +1,426 @@
+// Package weatherapi adapts the internal weather API to weather data bundles.
+package weatherapi
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/fileutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type Client struct {
+	baseURL       *url.URL
+	httpClient    *http.Client
+	units         string
+	format        string
+	timezone      string
+	precision     int
+	missingSource config.MissingSourceConfig
+	now           func() time.Time
+}
+
+type Option func(*Client)
+
+func WithHTTPClient(httpClient *http.Client) Option {
+	return func(c *Client) {
+		if httpClient != nil {
+			c.httpClient = httpClient
+		}
+	}
+}
+
+func WithClock(now func() time.Time) Option {
+	return func(c *Client) {
+		if now != nil {
+			c.now = now
+		}
+	}
+}
+
+func New(cfg config.Config, opts ...Option) (*Client, error) {
+	if strings.TrimSpace(cfg.WeatherAPI.BaseURL) == "" {
+		return nil, fmt.Errorf("weather_api.base_url is required")
+	}
+	baseURL, err := url.Parse(cfg.WeatherAPI.BaseURL)
+	if err != nil || baseURL.Scheme == "" || baseURL.Host == "" {
+		return nil, fmt.Errorf("weather_api.base_url must be an absolute URL")
+	}
+
+	timeout := cfg.WeatherAPI.Timeout
+	if timeout <= 0 {
+		timeout = 10 * time.Second
+	}
+
+	client := &Client{
+		baseURL:    baseURL,
+		httpClient: &http.Client{Timeout: timeout},
+		units:      cfg.WeatherAPI.Units,
+		format:     cfg.WeatherAPI.Format,
+		timezone:   cfg.WeatherAPI.Timezone,
+		precision:  cfg.WeatherAPI.Precision,
+		missingSource: config.MissingSourceConfig{
+			Default: cfg.MissingSource.Default,
+			Sources: cfg.MissingSource.Sources,
+		},
+		now: time.Now,
+	}
+	for _, opt := range opts {
+		opt(client)
+	}
+	return client, nil
+}
+
+func (c *Client) FetchBundle(ctx context.Context) (*weatherdata.Bundle, error) {
+	fetchedAt := c.now()
+	builder := bundleBuilder{
+		client:    c,
+		bundle:    &weatherdata.Bundle{FetchedAt: fetchedAt},
+		fetchedAt: fetchedAt,
+	}
+
+	if err := builder.fetchObservation(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchCurrent(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchHourly(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchNarrative(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchAlerts(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchDiscussion(ctx); err != nil {
+		return nil, err
+	}
+	if err := builder.fetchWeatherStory(ctx); err != nil {
+		return nil, err
+	}
+
+	return builder.bundle, nil
+}
+
+type bundleBuilder struct {
+	client    *Client
+	bundle    *weatherdata.Bundle
+	fetchedAt time.Time
+}
+
+func (b *bundleBuilder) fetchObservation(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "observations", "/observations", queryOptions{precision: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "observation data is missing", false)
+	}
+	var observation weatherdata.Observation
+	if err := decodeSource(raw, &observation); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	source.IssuedAt = &observation.Timestamp
+	b.bundle.Observation = &observation
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchCurrent(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "current", "/conditions/current", queryOptions{precision: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "current conditions data is missing", false)
+	}
+	var current weatherdata.Current
+	if err := decodeSource(raw, &current); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	b.bundle.Current = &current
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchHourly(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "hourly", "/forecast/hourly", queryOptions{precision: true, timezone: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "hourly forecast data is missing", true)
+	}
+	var hourly weatherdata.ForecastRun
+	if err := decodeSource(raw, &hourly); err != nil {
+		return fmt.Errorf("decode hourly forecast from %s: %w", source.Endpoint, err)
+	}
+	if len(hourly.Periods) == 0 {
+		return fmt.Errorf("hourly forecast from %s contains no periods", source.Endpoint)
+	}
+	source.IssuedAt = &hourly.IssuedAt
+	source.UpdatedAt = hourly.UpdatedAt
+	b.bundle.Hourly = &hourly
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchNarrative(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "narrative", "/forecast/narrative", queryOptions{precision: true, timezone: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "narrative forecast data is missing", false)
+	}
+	var narrative weatherdata.ForecastRun
+	if err := decodeSource(raw, &narrative); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	source.IssuedAt = &narrative.IssuedAt
+	source.UpdatedAt = narrative.UpdatedAt
+	b.bundle.Narrative = &narrative
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchAlerts(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "alerts", "/alerts/active", queryOptions{allowNull: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "active alerts data is missing", false)
+	}
+	if isJSONNull(raw) {
+		b.bundle.Alerts = &weatherdata.AlertRun{Raw: append(json.RawMessage(nil), raw...)}
+		b.addSource(source)
+		return nil
+	}
+	var alerts weatherdata.AlertRun
+	if err := decodeSource(raw, &alerts); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	alerts.Raw = append(json.RawMessage(nil), raw...)
+	if alerts.AsOf != nil {
+		source.IssuedAt = alerts.AsOf
+	}
+	b.bundle.Alerts = &alerts
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchDiscussion(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "discussion", "/discussion", queryOptions{timezone: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "forecast discussion data is missing", false)
+	}
+	var discussion weatherdata.Discussion
+	if err := decodeSource(raw, &discussion); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	source.IssuedAt = &discussion.IssuedAt
+	source.UpdatedAt = discussion.UpdatedAt
+	b.bundle.Discussion = &discussion
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) fetchWeatherStory(ctx context.Context) error {
+	raw, source, err := b.client.fetch(ctx, "weather_story", "/weatherstories/latest", queryOptions{omitUnits: true})
+	if err != nil {
+		return err
+	}
+	if raw == nil {
+		return b.handleMissing(&source, "NWS weather story data is missing", false)
+	}
+	var story weatherdata.WeatherStory
+	if err := decodeSource(raw, &story); err != nil {
+		return b.handleMalformed(&source, err, false)
+	}
+	if !story.StartTime.IsZero() {
+		source.IssuedAt = &story.StartTime
+	}
+	source.UpdatedAt = story.UpdatedAt
+	b.bundle.WeatherStory = &story
+	b.addSource(source)
+	return nil
+}
+
+func (b *bundleBuilder) handleMissing(source *weatherdata.Source, message string, required bool) error {
+	source.Missing = true
+	if required {
+		return fmt.Errorf("%s from %s is required", message, source.Endpoint)
+	}
+	return b.applyMissingPolicy(source, "missing_source", message)
+}
+
+func (b *bundleBuilder) handleMalformed(source *weatherdata.Source, err error, required bool) error {
+	if required {
+		return fmt.Errorf("decode %s from %s: %w", source.Name, source.Endpoint, err)
+	}
+	source.Missing = true
+	return b.applyMissingPolicy(source, "malformed_source", fmt.Sprintf("malformed %s data: %v", source.Name, err))
+}
+
+func (b *bundleBuilder) applyMissingPolicy(source *weatherdata.Source, code string, message string) error {
+	policy := b.client.policyFor(source.Name)
+	if policy == config.MissingSourceError {
+		return fmt.Errorf("%s: %s", source.Name, message)
+	}
+	if policy == config.MissingSourceWarn {
+		warning := weatherdata.SourceWarning{
+			Source:             source.Name,
+			Code:               code,
+			Severity:           "warning",
+			Message:            message,
+			Endpoint:           source.Endpoint,
+			CompletenessImpact: "source omitted from bundle",
+		}
+		source.Warnings = append(source.Warnings, warning)
+		b.bundle.Warnings = append(b.bundle.Warnings, warning)
+	}
+	b.addSource(*source)
+	return nil
+}
+
+func (b *bundleBuilder) addSource(source weatherdata.Source) {
+	b.bundle.Sources = append(b.bundle.Sources, source)
+}
+
+func (c *Client) policyFor(source string) config.MissingSourcePolicy {
+	if policy, ok := c.missingSource.Sources[source]; ok {
+		return policy
+	}
+	return c.missingSource.Default
+}
+
+type queryOptions struct {
+	precision bool
+	timezone  bool
+	allowNull bool
+	omitUnits bool
+}
+
+type envelope struct {
+	Data json.RawMessage `json:"data"`
+}
+
+func (c *Client) fetch(ctx context.Context, sourceName string, endpoint string, opts queryOptions) (json.RawMessage, weatherdata.Source, error) {
+	reqURL := c.endpointURL(endpoint, opts)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, reqURL.String(), nil)
+	if err != nil {
+		return nil, weatherdata.Source{}, fmt.Errorf("create request for %s: %w", endpoint, err)
+	}
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, weatherdata.Source{}, fmt.Errorf("fetch %s: %w", endpoint, err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 10<<20))
+	if err != nil {
+		return nil, weatherdata.Source{}, fmt.Errorf("read %s response: %w", endpoint, err)
+	}
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return nil, weatherdata.Source{}, fmt.Errorf("fetch %s: unexpected HTTP status %d: %s", endpoint, resp.StatusCode, strings.TrimSpace(string(body)))
+	}
+
+	var env envelope
+	if err := json.Unmarshal(body, &env); err != nil {
+		return nil, weatherdata.Source{}, fmt.Errorf("decode %s envelope: %w", endpoint, err)
+	}
+
+	source := weatherdata.Source{
+		Name:      sourceName,
+		Endpoint:  endpoint,
+		Query:     queryMap(reqURL.Query()),
+		FetchedAt: c.now(),
+	}
+	if len(env.Data) == 0 || (isJSONNull(env.Data) && !opts.allowNull) {
+		source.Missing = true
+		return nil, source, nil
+	}
+	hash, err := sourceHash(env.Data)
+	if err != nil {
+		return env.Data, source, nil
+	}
+	source.DataSHA256 = hash
+	return env.Data, source, nil
+}
+
+func isJSONNull(raw json.RawMessage) bool {
+	return bytes.Equal(bytes.TrimSpace(raw), []byte("null"))
+}
+
+func (c *Client) endpointURL(endpoint string, opts queryOptions) *url.URL {
+	reqURL := *c.baseURL
+	reqURL.Path = path.Join(c.baseURL.Path, endpoint)
+	query := reqURL.Query()
+	query.Set("format", c.format)
+	if !opts.omitUnits {
+		query.Set("units", c.units)
+	}
+	if opts.precision {
+		query.Set("precision", strconv.Itoa(c.precision))
+	}
+	if opts.timezone {
+		query.Set("tz", c.timezone)
+	}
+	reqURL.RawQuery = query.Encode()
+	return &reqURL
+}
+
+func queryMap(values url.Values) map[string]string {
+	if len(values) == 0 {
+		return nil
+	}
+	out := make(map[string]string, len(values))
+	for key, value := range values {
+		if len(value) > 0 {
+			out[key] = value[0]
+		}
+	}
+	return out
+}
+
+func decodeSource(raw json.RawMessage, target any) error {
+	if err := json.Unmarshal(raw, target); err != nil {
+		return err
+	}
+	return nil
+}
+
+func sourceHash(raw json.RawMessage) (string, error) {
+	var compact bytes.Buffer
+	if err := json.Compact(&compact, raw); err != nil {
+		return "", err
+	}
+	sum := sha256.Sum256(compact.Bytes())
+	return hex.EncodeToString(sum[:]), nil
+}
+
+func SaveBundle(path string, bundle *weatherdata.Bundle) error {
+	if err := fileutil.WriteJSONAtomic(path, bundle); err != nil {
+		return fmt.Errorf("save bundle: %w", err)
+	}
+	return nil
+}

internal/adapters/weatherapi/client_test.go

@@ -0,0 +1,452 @@
+package weatherapi
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+func TestFetchBundleFromFixtures(t *testing.T) {
+	var requested []string
+	server := fixtureServer(t, nil, &requested)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+
+	if bundle.Observation == nil || bundle.Observation.StationID != "KSTL" {
+		t.Fatalf("Observation = %#v, want KSTL observation", bundle.Observation)
+	}
+	if bundle.Current == nil || bundle.Current.ConditionText != "Partly cloudy" {
+		t.Fatalf("Current = %#v, want current conditions", bundle.Current)
+	}
+	if bundle.Hourly == nil || len(bundle.Hourly.Periods) != 1 {
+		t.Fatalf("Hourly = %#v, want one hourly period", bundle.Hourly)
+	}
+	if bundle.Narrative == nil || bundle.Narrative.Product != "narrative" {
+		t.Fatalf("Narrative = %#v, want narrative product", bundle.Narrative)
+	}
+	if bundle.Alerts == nil || bundle.Alerts.AsOf == nil {
+		t.Fatalf("Alerts = %#v, want alert run", bundle.Alerts)
+	}
+	if bundle.Discussion == nil || len(bundle.Discussion.KeyMessages) != 2 {
+		t.Fatalf("Discussion = %#v, want key messages", bundle.Discussion)
+	}
+	if bundle.Discussion.ShortTerm == nil || bundle.Discussion.ShortTerm.Text != "A weak boundary may trigger isolated showers." {
+		t.Fatalf("Discussion.ShortTerm = %#v, want short-term AFD text", bundle.Discussion.ShortTerm)
+	}
+	if bundle.Discussion.LongTerm == nil || bundle.Discussion.LongTerm.Text != "Warmer temperatures and periodic rain chances continue into the weekend." {
+		t.Fatalf("Discussion.LongTerm = %#v, want long-term AFD text", bundle.Discussion.LongTerm)
+	}
+	if bundle.WeatherStory == nil || bundle.WeatherStory.Title != "Several Chances for Rain Through Monday" {
+		t.Fatalf("WeatherStory = %#v, want latest weather story", bundle.WeatherStory)
+	}
+	if bundle.WeatherStory.UpdatedAt == nil {
+		t.Fatalf("WeatherStory.UpdatedAt = nil, want update timestamp")
+	}
+	if len(bundle.Sources) != 7 {
+		t.Fatalf("Sources length = %d, want 7", len(bundle.Sources))
+	}
+	if len(bundle.Warnings) != 0 {
+		t.Fatalf("Warnings length = %d, want no warnings", len(bundle.Warnings))
+	}
+	if !containsPath(requested, "/forecast/hourly") || containsPath(requested, "/forecast/hourly/today") {
+		t.Fatalf("requested paths = %v, want full hourly endpoint only", requested)
+	}
+	if !containsPath(requested, "/forecast/narrative") || containsPath(requested, "/forecast/narrative/today") {
+		t.Fatalf("requested paths = %v, want full narrative endpoint only", requested)
+	}
+	if !containsPath(requested, "/weatherstories/latest") {
+		t.Fatalf("requested paths = %v, want weather story endpoint", requested)
+	}
+}
+
+func TestFetchBundleBuildsExpectedQueries(t *testing.T) {
+	var requested []string
+	server := fixtureServer(t, nil, &requested)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	_, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+
+	for _, rawURL := range requested {
+		if !strings.Contains(rawURL, "format=json") {
+			t.Fatalf("request %q missing format=json", rawURL)
+		}
+		if strings.HasPrefix(rawURL, "/weatherstories/") {
+			if strings.Contains(rawURL, "units=") || strings.Contains(rawURL, "precision=") || strings.Contains(rawURL, "tz=") {
+				t.Fatalf("weather story request %q should use format only", rawURL)
+			}
+			continue
+		}
+		if !strings.Contains(rawURL, "units=us") {
+			t.Fatalf("request %q missing units=us", rawURL)
+		}
+		if strings.HasPrefix(rawURL, "/forecast/") {
+			if !strings.Contains(rawURL, "precision=1") || !strings.Contains(rawURL, "tz=America%2FChicago") {
+				t.Fatalf("forecast request %q missing precision or tz", rawURL)
+			}
+		}
+	}
+}
+
+func TestFetchBundleRecordsSourceHash(t *testing.T) {
+	server := fixtureServer(t, nil, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+
+	observation := sourceByName(t, bundle.Sources, "observations")
+	want := hashFixtureData(t, "observations.json")
+	if observation.DataSHA256 != want {
+		t.Fatalf("DataSHA256 = %q, want %q", observation.DataSHA256, want)
+	}
+	story := sourceByName(t, bundle.Sources, "weather_story")
+	if story.Endpoint != "/weatherstories/latest" {
+		t.Fatalf("weather story endpoint = %q, want /weatherstories/latest", story.Endpoint)
+	}
+	if story.DataSHA256 != hashFixtureData(t, "weather_story.json") {
+		t.Fatalf("weather story DataSHA256 = %q, want fixture hash", story.DataSHA256)
+	}
+	if story.IssuedAt == nil || story.UpdatedAt == nil {
+		t.Fatalf("weather story source timestamps = issued %#v updated %#v, want both", story.IssuedAt, story.UpdatedAt)
+	}
+}
+
+func TestHTTPErrorIsActionable(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/conditions/current": {status: http.StatusBadGateway, body: `upstream failed`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	_, err := client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want HTTP error")
+	}
+	if !strings.Contains(err.Error(), "/conditions/current") || !strings.Contains(err.Error(), "502") {
+		t.Fatalf("error = %q, want endpoint and status", err.Error())
+	}
+}
+
+func TestRequiredHourlyForecast(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/forecast/hourly": {status: http.StatusOK, body: `{"data": null}`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	_, err := client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want required hourly error")
+	}
+	if !strings.Contains(err.Error(), "hourly forecast data") {
+		t.Fatalf("error = %q, want hourly context", err.Error())
+	}
+}
+
+func TestNullAlertsMeansNoActiveAlerts(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/alerts/active": {status: http.StatusOK, body: `{"data": null}`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+	if bundle.Alerts == nil {
+		t.Fatal("Alerts = nil, want checked empty alert run")
+	}
+	if len(bundle.Alerts.Alerts) != 0 {
+		t.Fatalf("Alerts length = %d, want no active alerts", len(bundle.Alerts.Alerts))
+	}
+	source := sourceByName(t, bundle.Sources, "alerts")
+	if source.Missing {
+		t.Fatalf("alerts source Missing = true, want false")
+	}
+	if source.DataSHA256 == "" {
+		t.Fatal("alerts DataSHA256 is empty, want hash for explicit null payload")
+	}
+	for _, warning := range bundle.Warnings {
+		if warning.Source == "alerts" {
+			t.Fatalf("warnings = %#v, want no alerts warning", bundle.Warnings)
+		}
+	}
+}
+
+func TestMissingSourcePolicyWarnNoneError(t *testing.T) {
+	tests := []struct {
+		name       string
+		policy     config.MissingSourcePolicy
+		wantErr    bool
+		wantWarns  int
+		wantSource bool
+	}{
+		{name: "warn", policy: config.MissingSourceWarn, wantWarns: 1, wantSource: true},
+		{name: "none", policy: config.MissingSourceNone, wantWarns: 0, wantSource: true},
+		{name: "error", policy: config.MissingSourceError, wantErr: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := fixtureServer(t, map[string]handlerOverride{
+				"/observations": {status: http.StatusOK, body: `{"data": null}`},
+			}, nil)
+			cfg := testConfig(server.URL + "/")
+			cfg.MissingSource.Default = tt.policy
+			cfg.MissingSource.Sources = map[string]config.MissingSourcePolicy{
+				"hourly": tt.policy,
+			}
+			client, err := New(cfg, WithClock(fixedNow))
+			if err != nil {
+				t.Fatalf("New() error = %v", err)
+			}
+
+			bundle, err := client.FetchBundle(context.Background())
+			if tt.wantErr {
+				if err == nil {
+					t.Fatal("FetchBundle() error = nil, want policy error")
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("FetchBundle() error = %v", err)
+			}
+			if len(bundle.Warnings) != tt.wantWarns {
+				t.Fatalf("Warnings length = %d, want %d", len(bundle.Warnings), tt.wantWarns)
+			}
+			if tt.wantSource {
+				source := sourceByName(t, bundle.Sources, "observations")
+				if !source.Missing {
+					t.Fatalf("observations source Missing = false, want true")
+				}
+			}
+		})
+	}
+}
+
+func TestMalformedNonRequiredSourceUsesPolicy(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/conditions/current": {status: http.StatusOK, body: `{"data": {"temperatureF": "hot"}}`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", map[string]config.MissingSourcePolicy{
+		"current": config.MissingSourceWarn,
+	})
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+	source := sourceByName(t, bundle.Sources, "current")
+	if !source.Missing || len(source.Warnings) != 1 {
+		t.Fatalf("current source = %#v, want missing source warning", source)
+	}
+}
+
+func TestMissingWeatherStoryUsesPolicy(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/weatherstories/latest": {status: http.StatusOK, body: `{"data": null}`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", map[string]config.MissingSourcePolicy{
+		"weather_story": config.MissingSourceWarn,
+	})
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+	if bundle.WeatherStory != nil {
+		t.Fatalf("WeatherStory = %#v, want nil for missing source", bundle.WeatherStory)
+	}
+	source := sourceByName(t, bundle.Sources, "weather_story")
+	if !source.Missing || len(source.Warnings) != 1 {
+		t.Fatalf("weather_story source = %#v, want missing source warning", source)
+	}
+}
+
+func TestMalformedWeatherStoryUsesPolicy(t *testing.T) {
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/weatherstories/latest": {status: http.StatusOK, body: `{"data": {"startTime": 123}}`},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", map[string]config.MissingSourcePolicy{
+		"weather_story": config.MissingSourceWarn,
+	})
+
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+	source := sourceByName(t, bundle.Sources, "weather_story")
+	if !source.Missing || len(source.Warnings) != 1 || source.Warnings[0].Code != "malformed_source" {
+		t.Fatalf("weather_story source = %#v, want malformed source warning", source)
+	}
+}
+
+func TestContextCancellation(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		<-r.Context().Done()
+	}))
+	defer server.Close()
+	client := newTestClient(t, server.URL+"/", nil)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	_, err := client.FetchBundle(ctx)
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want cancellation error")
+	}
+}
+
+func TestHTTPTimeout(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(50 * time.Millisecond)
+	}))
+	defer server.Close()
+
+	cfg := testConfig(server.URL + "/")
+	cfg.WeatherAPI.Timeout = time.Nanosecond
+	client, err := New(cfg, WithClock(fixedNow))
+	if err != nil {
+		t.Fatalf("New() error = %v", err)
+	}
+
+	_, err = client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want timeout error")
+	}
+	if !strings.Contains(err.Error(), "/observations") {
+		t.Fatalf("error = %q, want endpoint context", err.Error())
+	}
+}
+
+func TestSaveBundle(t *testing.T) {
+	server := fixtureServer(t, nil, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+	bundle, err := client.FetchBundle(context.Background())
+	if err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+
+	path := filepath.Join(t.TempDir(), "nested", "bundle.json")
+	if err := SaveBundle(path, bundle); err != nil {
+		t.Fatalf("SaveBundle() error = %v", err)
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("read saved bundle: %v", err)
+	}
+	if !strings.Contains(string(data), `"hourly"`) {
+		t.Fatalf("saved bundle missing hourly source:\n%s", string(data))
+	}
+}
+
+type handlerOverride struct {
+	status int
+	body   string
+}
+
+func fixtureServer(t *testing.T, overrides map[string]handlerOverride, requested *[]string) *httptest.Server {
+	t.Helper()
+	fixtures := map[string]string{
+		"/observations":          "observations.json",
+		"/conditions/current":    "current.json",
+		"/forecast/hourly":       "hourly.json",
+		"/forecast/narrative":    "narrative.json",
+		"/alerts/active":         "alerts.json",
+		"/discussion":            "discussion.json",
+		"/weatherstories/latest": "weather_story.json",
+	}
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if requested != nil {
+			*requested = append(*requested, r.URL.String())
+		}
+		if override, ok := overrides[r.URL.Path]; ok {
+			w.WriteHeader(override.status)
+			_, _ = w.Write([]byte(override.body))
+			return
+		}
+		name, ok := fixtures[r.URL.Path]
+		if !ok {
+			http.NotFound(w, r)
+			return
+		}
+		http.ServeFile(w, r, filepath.Join("testdata", name))
+	}))
+	t.Cleanup(server.Close)
+	return server
+}
+
+func newTestClient(t *testing.T, baseURL string, sourcePolicies map[string]config.MissingSourcePolicy) *Client {
+	t.Helper()
+	cfg := testConfig(baseURL)
+	for source, policy := range sourcePolicies {
+		cfg.MissingSource.Sources[source] = policy
+	}
+	client, err := New(cfg, WithClock(fixedNow))
+	if err != nil {
+		t.Fatalf("New() error = %v", err)
+	}
+	return client
+}
+
+func testConfig(baseURL string) config.Config {
+	cfg := config.Defaults()
+	cfg.WeatherAPI.BaseURL = baseURL
+	return cfg
+}
+
+func fixedNow() time.Time {
+	return time.Date(2026, 5, 29, 15, 0, 0, 0, time.UTC)
+}
+
+func containsPath(requested []string, path string) bool {
+	for _, rawURL := range requested {
+		if strings.HasPrefix(rawURL, path+"?") || rawURL == path {
+			return true
+		}
+	}
+	return false
+}
+
+func sourceByName(t *testing.T, sources []weatherdata.Source, name string) weatherdata.Source {
+	t.Helper()
+	for _, source := range sources {
+		if source.Name == name {
+			return source
+		}
+	}
+	t.Fatalf("source %q not found in %#v", name, sources)
+	return weatherdata.Source{}
+}
+
+func hashFixtureData(t *testing.T, fixture string) string {
+	t.Helper()
+	data, err := os.ReadFile(filepath.Join("testdata", fixture))
+	if err != nil {
+		t.Fatalf("read fixture: %v", err)
+	}
+	var env envelope
+	if err := json.Unmarshal(data, &env); err != nil {
+		t.Fatalf("decode fixture envelope: %v", err)
+	}
+	hash, err := sourceHash(env.Data)
+	if err != nil {
+		t.Fatalf("hash fixture data: %v", err)
+	}
+	return hash
+}

internal/adapters/weatherapi/testdata/alerts.json

@@ -0,0 +1,6 @@
+{
+  "data": {
+    "asOf": "2026-05-29T14:00:00Z",
+    "alerts": []
+  }
+}

internal/adapters/weatherapi/testdata/current.json

@@ -0,0 +1,10 @@
+{
+  "data": {
+    "conditionText": "Partly cloudy",
+    "isDay": true,
+    "temperatureF": 75.9,
+    "apparentTemperatureF": 76.1,
+    "windSpeedMph": 10.7,
+    "relativeHumidityPercent": 56
+  }
+}

internal/adapters/weatherapi/testdata/discussion.json

@@ -0,0 +1,20 @@
+{
+  "data": {
+    "officeId": "LSX",
+    "officeName": "St. Louis",
+    "product": "discussion",
+    "issuedAt": "2026-05-29T09:25:00-05:00",
+    "keyMessages": [
+      "Scattered showers possible this evening.",
+      "Warmer temperatures this weekend."
+    ],
+    "shortTerm": {
+      "qualifier": "(Through This Evening)",
+      "text": "A weak boundary may trigger isolated showers."
+    },
+    "longTerm": {
+      "qualifier": "(This Weekend)",
+      "text": "Warmer temperatures and periodic rain chances continue into the weekend."
+    }
+  }
+}

internal/adapters/weatherapi/testdata/hourly.json

@@ -0,0 +1,25 @@
+{
+  "data": {
+    "locationId": "nws-lsx-grid-90-74",
+    "locationName": "St. Louis, MO",
+    "issuedAt": "2026-05-29T10:30:00-05:00",
+    "updatedAt": "2026-05-29T10:45:00-05:00",
+    "product": "hourly",
+    "latitude": 38.63,
+    "longitude": -90.2,
+    "elevationFeet": 466,
+    "periods": [
+      {
+        "startTime": "2026-05-29T13:00:00-05:00",
+        "endTime": "2026-05-29T14:00:00-05:00",
+        "isDay": true,
+        "conditionCode": 3,
+        "textDescription": "Partly sunny",
+        "temperatureF": 81,
+        "windSpeedMph": 12,
+        "windGustMph": 20,
+        "probabilityOfPrecipitationPercent": 10
+      }
+    ]
+  }
+}

internal/adapters/weatherapi/testdata/narrative.json

@@ -0,0 +1,20 @@
+{
+  "data": {
+    "locationId": "nws-lsx-grid-90-74",
+    "locationName": "St. Louis, MO",
+    "issuedAt": "2026-05-29T10:30:00-05:00",
+    "product": "narrative",
+    "periods": [
+      {
+        "startTime": "2026-05-29T13:00:00-05:00",
+        "endTime": "2026-05-29T19:00:00-05:00",
+        "name": "Today",
+        "isDay": true,
+        "textDescription": "Partly sunny, with a high near 81.",
+        "temperatureF": 81,
+        "windSpeedMph": 12,
+        "probabilityOfPrecipitationPercent": 10
+      }
+    ]
+  }
+}

internal/adapters/weatherapi/testdata/observations.json

@@ -0,0 +1,13 @@
+{
+  "data": {
+    "stationId": "KSTL",
+    "stationName": "St. Louis",
+    "timestamp": "2026-05-29T14:00:00Z",
+    "conditionCode": 3,
+    "isDay": true,
+    "textDescription": "Partly cloudy",
+    "temperatureF": 75.9,
+    "windSpeedMph": 10.7,
+    "relativeHumidityPercent": 56
+  }
+}

internal/adapters/weatherapi/testdata/weather_story.json

@@ -0,0 +1,14 @@
+{
+  "data": {
+    "officeId": "LSX",
+    "startTime": "2026-05-30T08:46:00Z",
+    "endTime": "2026-05-31T11:00:00Z",
+    "updatedAt": "2026-05-30T09:00:34Z",
+    "title": "Several Chances for Rain Through Monday",
+    "description": "A stagnant weather pattern with low pressure over the Great Plains and high pressure over the Great Lakes will continue to produce scattered showers and thunderstorms, for areas mainly along and west of the Mississippi River today and Sunday.",
+    "altText": "This slide shows the forecast for today through Tuesday with icons for showers and thunderstorms and a picture of a cumulonimbus cloud on the right side.",
+    "priority": false,
+    "order": 1,
+    "downloadUrl": "https://api.weather.gov/offices/LSX/weatherstories/download/3228e499-2aae-45a8-9ff9-1c060311026f"
+  }
+}

internal/app/app.go

@@ -0,0 +1,937 @@
+// Package app owns application orchestration and top-level use cases.
+package app
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"path/filepath"
+	"time"
+
+	distributoradapter "gitea.maximumdirect.net/eric/weatherreporter/internal/adapters/distributor"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/adapters/scriptorium"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/adapters/weatherapi"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/briefing"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/changes"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/fileutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/promptinput"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/state"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type ReportKind string
+
+const (
+	ReportDaily    ReportKind = "daily"
+	ReportTomorrow ReportKind = "tomorrow"
+	ReportThreeDay ReportKind = "three-day"
+	ReportWeekend  ReportKind = "weekend"
+	ReportStorm    ReportKind = "storm"
+)
+
+type BatchKind string
+
+const (
+	BatchMorning BatchKind = "morning"
+	BatchEvening BatchKind = "evening"
+)
+
+type GenerateRequest struct {
+	Config     config.Config
+	Report     ReportKind
+	OutputPath string
+	Now        time.Time
+	Date       time.Time
+	StormStart time.Time
+	StormEnd   time.Time
+	Notifier   Notifier
+}
+
+type BatchRequest struct {
+	Config    config.Config
+	Batch     BatchKind
+	Now       time.Time
+	OutputDir string
+	Renderer  Renderer
+	Store     state.Store
+	Notifier  Notifier
+}
+
+type FetchBundleRequest struct {
+	Config     config.Config
+	OutputPath string
+}
+
+type ModuleSnapshotRequest struct {
+	Config   config.Config
+	Resolved report.Resolved
+}
+
+type ReportFacts struct {
+	Collected facts.CollectedFacts
+	Derived   facts.DerivedFacts
+}
+
+type ReportRequest struct {
+	Config     config.Config
+	Resolved   report.Resolved
+	OutputPath string
+	Renderer   Renderer
+	Store      state.Store
+	Notifier   Notifier
+}
+
+type ReportResult struct {
+	ModuleSnapshot     module.Snapshot
+	ModuleSnapshotPath string
+	DataPackage        promptinput.Package
+	DataPackagePath    string
+	PreflightPath      string
+	ReportPath         string
+	OutputPath         string
+	NotificationPath   string
+	Metadata           state.Metadata
+	MetadataPath       string
+	PriorSnapshot      *state.PriorSnapshot
+	RecentChanges      []changes.Change
+	RenderResult       *scriptorium.RenderResult
+	RunResult          *scriptorium.RunResult
+	Notification       *NotificationResult
+}
+
+type BatchResult struct {
+	Batch      BatchKind           `json:"batch"`
+	StartedAt  time.Time           `json:"startedAt"`
+	FinishedAt time.Time           `json:"finishedAt"`
+	Total      int                 `json:"total"`
+	Succeeded  int                 `json:"succeeded"`
+	Failed     int                 `json:"failed"`
+	Reports    []BatchReportResult `json:"reports"`
+}
+
+type BatchReportResult struct {
+	ReportID               report.ID       `json:"reportId"`
+	ReportName             string          `json:"reportName"`
+	PromptID               string          `json:"promptId"`
+	RunID                  string          `json:"runId"`
+	Status                 string          `json:"status"`
+	Error                  string          `json:"error,omitempty"`
+	NotificationStatus     string          `json:"notificationStatus,omitempty"`
+	NotificationRunID      string          `json:"notificationRunId,omitempty"`
+	NotificationPipelineID string          `json:"notificationPipelineId,omitempty"`
+	NotificationError      string          `json:"notificationError,omitempty"`
+	NotificationPath       string          `json:"notificationPath,omitempty"`
+	GeneratedAt            time.Time       `json:"generatedAt"`
+	ValidPeriod            timeutil.Period `json:"validPeriod"`
+	DataPackagePath        string          `json:"dataPackagePath,omitempty"`
+	PreflightPath          string          `json:"preflightPath,omitempty"`
+	ReportPath             string          `json:"reportPath,omitempty"`
+	OutputPath             string          `json:"outputPath,omitempty"`
+	MetadataPath           string          `json:"metadataPath,omitempty"`
+}
+
+type BatchError struct {
+	Result *BatchResult
+}
+
+func (e BatchError) Error() string {
+	if e.Result == nil {
+		return "batch failed"
+	}
+	return fmt.Sprintf("batch %s failed: %d of %d reports failed", e.Result.Batch, e.Result.Failed, e.Result.Total)
+}
+
+type Renderer interface {
+	Render(context.Context, scriptorium.RenderRequest) (*scriptorium.RenderResult, error)
+	Run(context.Context, scriptorium.RunRequest) (*scriptorium.RunResult, error)
+}
+
+type Notifier interface {
+	Notify(context.Context, NotificationRequest) (*NotificationResult, error)
+}
+
+type NotificationRequest struct {
+	ReportID       report.ID
+	RunID          string
+	PipelineID     string
+	BundleID       string
+	IdempotencyKey string
+	ReportPath     string
+	BundlePaths    []string
+	CreatedAt      time.Time
+}
+
+type NotificationResult struct {
+	BundleID       string
+	IdempotencyKey string
+	RunID          string
+	Status         string
+	UploadStatus   string
+	StatusError    string
+	PipelineID     string
+	AcceptedAt     time.Time
+	StartedAt      *time.Time
+	FinishedAt     *time.Time
+	Report         []byte
+	Error          string
+}
+
+type NotificationError struct {
+	Request NotificationRequest
+	Err     error
+}
+
+func (e *NotificationError) Error() string {
+	if e == nil || e.Err == nil {
+		return "notification failed"
+	}
+	return e.Err.Error()
+}
+
+func (e *NotificationError) Unwrap() error {
+	if e == nil {
+		return nil
+	}
+	return e.Err
+}
+
+func Generate(ctx context.Context, req GenerateRequest) error {
+	now := req.Now
+	if now.IsZero() {
+		now = time.Now()
+	}
+	resolved, err := ResolveGenerate(req, now)
+	if err != nil {
+		return err
+	}
+	if resolved.Definition.Generated {
+		_, err := GenerateReport(ctx, ReportRequest{
+			Config:     req.Config,
+			Resolved:   resolved,
+			OutputPath: req.OutputPath,
+			Notifier:   req.Notifier,
+		})
+		return err
+	}
+	return fmt.Errorf("generate is not implemented")
+}
+
+func RunBatch(ctx context.Context, req BatchRequest) error {
+	result, err := RunBatchDetailed(ctx, req)
+	if err != nil {
+		return err
+	}
+	if result.Failed > 0 {
+		return BatchError{Result: result}
+	}
+	return nil
+}
+
+func RunBatchDetailed(ctx context.Context, req BatchRequest) (*BatchResult, error) {
+	now := req.Now
+	if now.IsZero() {
+		now = time.Now()
+	}
+	resolvedReports, err := ResolveBatch(req, now)
+	if err != nil {
+		return nil, err
+	}
+	if req.Batch == BatchEvening || req.Batch == BatchMorning {
+		store := req.Store
+		if store == nil {
+			defaultStore, err := defaultStore(req.Config)
+			if err != nil {
+				return nil, err
+			}
+			store = defaultStore
+		}
+		startedAt := now
+		result := &BatchResult{Batch: req.Batch, StartedAt: startedAt}
+		for _, resolved := range resolvedReports {
+			if !resolved.Definition.Generated {
+				return nil, fmt.Errorf("run is not implemented")
+			}
+		}
+		for _, resolved := range resolvedReports {
+			item := batchReportResult(resolved)
+			if paths, err := store.Paths(resolved); err == nil {
+				item.DataPackagePath = paths.DataPackage
+				item.PreflightPath = paths.Preflight
+				item.ReportPath = paths.RenderedReport
+				item.MetadataPath = paths.Metadata
+			}
+			outputPath := batchOutputPath(req.OutputDir, resolved.Definition)
+			reportResult, err := GenerateReport(ctx, ReportRequest{
+				Config:     req.Config,
+				Resolved:   resolved,
+				OutputPath: outputPath,
+				Renderer:   req.Renderer,
+				Store:      store,
+				Notifier:   req.Notifier,
+			})
+			if err != nil {
+				item.Status = "failed"
+				item.Error = err.Error()
+				var notificationErr *NotificationError
+				if errors.As(err, &notificationErr) {
+					item.NotificationStatus = "failed"
+					item.NotificationError = notificationErr.Error()
+					item.NotificationPipelineID = notificationErr.Request.PipelineID
+					if paths, pathErr := store.Paths(resolved); pathErr == nil {
+						item.NotificationPath = paths.Notification
+					}
+				}
+				result.Failed++
+			} else {
+				item.Status = "succeeded"
+				item.DataPackagePath = reportResult.DataPackagePath
+				item.PreflightPath = reportResult.PreflightPath
+				item.ReportPath = reportResult.ReportPath
+				item.OutputPath = reportResult.OutputPath
+				item.MetadataPath = reportResult.MetadataPath
+				item.NotificationPath = reportResult.NotificationPath
+				if reportResult.Notification != nil {
+					item.NotificationStatus = reportResult.Notification.Status
+					item.NotificationRunID = reportResult.Notification.RunID
+					item.NotificationPipelineID = reportResult.Notification.PipelineID
+				}
+				result.Succeeded++
+			}
+			result.Reports = append(result.Reports, item)
+		}
+		result.Total = len(result.Reports)
+		result.FinishedAt = time.Now()
+		return result, nil
+	}
+	return nil, fmt.Errorf("run is not implemented")
+}
+
+func batchReportResult(resolved report.Resolved) BatchReportResult {
+	metadata := resolved.Metadata()
+	return BatchReportResult{
+		ReportID:    resolved.Definition.ID,
+		ReportName:  resolved.Definition.Name,
+		PromptID:    resolved.Definition.PromptID,
+		RunID:       metadata.RunID,
+		GeneratedAt: metadata.GeneratedAt,
+		ValidPeriod: metadata.ValidPeriod,
+	}
+}
+
+func batchOutputPath(outputDir string, definition report.Definition) string {
+	if outputDir == "" || definition.BatchOutputName == "" {
+		return ""
+	}
+	return filepath.Join(outputDir, definition.BatchOutputName)
+}
+
+func ResolveGenerate(req GenerateRequest, now time.Time) (report.Resolved, error) {
+	location, err := timeutil.LoadLocation(req.Config.WeatherAPI.Timezone)
+	if err != nil {
+		return report.Resolved{}, err
+	}
+	id, err := reportIDForCommand(req.Report)
+	if err != nil {
+		return report.Resolved{}, err
+	}
+	registry, err := reportRegistry(req.Config)
+	if err != nil {
+		return report.Resolved{}, err
+	}
+	return registry.Resolve(id, report.ResolveRequest{
+		Now:        now,
+		Location:   location,
+		Date:       req.Date,
+		StormStart: req.StormStart,
+		StormEnd:   req.StormEnd,
+	})
+}
+
+func ResolveBatch(req BatchRequest, now time.Time) ([]report.Resolved, error) {
+	location, err := timeutil.LoadLocation(req.Config.WeatherAPI.Timezone)
+	if err != nil {
+		return nil, err
+	}
+	batch, err := reportBatchForCommand(req.Batch)
+	if err != nil {
+		return nil, err
+	}
+	registry, err := reportRegistry(req.Config)
+	if err != nil {
+		return nil, err
+	}
+	return registry.BatchReports(batch, report.ResolveRequest{
+		Now:      now,
+		Location: location,
+	})
+}
+
+func reportRegistry(cfg config.Config) (report.Registry, error) {
+	registry, err := report.DefaultRegistry().WithModuleOverrides(cfg.ReportModuleOverrides())
+	if err != nil {
+		return report.Registry{}, err
+	}
+	return registry, nil
+}
+
+func reportIDForCommand(kind ReportKind) (report.ID, error) {
+	switch kind {
+	case ReportDaily:
+		return report.DailyToday, nil
+	case ReportTomorrow:
+		return report.DailyTomorrow, nil
+	case ReportThreeDay:
+		return report.ThreeDay, nil
+	case ReportWeekend:
+		return report.Weekend, nil
+	case ReportStorm:
+		return report.Storm, nil
+	default:
+		return "", fmt.Errorf("unknown report command %q", kind)
+	}
+}
+
+func reportBatchForCommand(kind BatchKind) (report.Batch, error) {
+	switch kind {
+	case BatchMorning:
+		return report.Morning, nil
+	case BatchEvening:
+		return report.Evening, nil
+	default:
+		return "", fmt.Errorf("unknown batch command %q", kind)
+	}
+}
+
+func FetchBundle(ctx context.Context, req FetchBundleRequest) (*weatherdata.Bundle, error) {
+	client, err := weatherapi.New(req.Config)
+	if err != nil {
+		return nil, err
+	}
+	bundle, err := client.FetchBundle(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return bundle, nil
+}
+
+func FetchAndSaveBundle(ctx context.Context, req FetchBundleRequest) (*weatherdata.Bundle, error) {
+	if req.OutputPath == "" {
+		return nil, fmt.Errorf("output path is required")
+	}
+	bundle, err := FetchBundle(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+	if err := weatherapi.SaveBundle(req.OutputPath, bundle); err != nil {
+		return nil, err
+	}
+	return bundle, nil
+}
+
+func GenerateReport(ctx context.Context, req ReportRequest) (*ReportResult, error) {
+	store := req.Store
+	if store == nil {
+		defaultStore, err := defaultStore(req.Config)
+		if err != nil {
+			return nil, err
+		}
+		store = defaultStore
+	}
+	paths, err := store.Paths(req.Resolved)
+	if err != nil {
+		return nil, err
+	}
+	priorSnapshot, err := store.FindPriorSnapshot(ctx, req.Resolved)
+	if err != nil {
+		return nil, err
+	}
+
+	bundle, err := FetchBundle(ctx, FetchBundleRequest{Config: req.Config})
+	if err != nil {
+		return nil, err
+	}
+	reportFacts, err := BuildReportFacts(ModuleSnapshotRequest{
+		Config:   req.Config,
+		Resolved: req.Resolved,
+	}, bundle)
+	if err != nil {
+		return nil, err
+	}
+	moduleSnapshot, err := BuildModuleSnapshotFromFacts(ModuleSnapshotRequest{
+		Config:   req.Config,
+		Resolved: req.Resolved,
+	}, reportFacts)
+	if err != nil {
+		return nil, err
+	}
+
+	moduleSnapshotPath, err := store.SaveModuleSnapshot(ctx, req.Resolved, moduleSnapshot)
+	if err != nil {
+		return nil, err
+	}
+
+	recentChanges, err := recentChanges(ctx, store, priorSnapshot, req.Resolved.Definition.ID, moduleSnapshot, req.Config.RecentChange)
+	if err != nil {
+		return nil, err
+	}
+	briefingMetadata := briefing.BuildMetadata(briefingBuildContext(req.Config, req.Resolved, reportFacts.Collected))
+	metadata := state.BuildMetadataFromBriefingMetadata(req.Resolved, briefingMetadata, state.ArtifactPaths{
+		ModuleSnapshot: moduleSnapshotPath,
+		Metadata:       paths.Metadata,
+		DataPackage:    paths.DataPackage,
+		Preflight:      paths.Preflight,
+		RenderedReport: paths.RenderedReport,
+	})
+	dataPackage, err := promptinput.Build(promptinput.BuildRequest{
+		Metadata:      promptMetadata(metadata),
+		Modules:       moduleSnapshot,
+		RecentChanges: recentChanges,
+	})
+	if err != nil {
+		return nil, err
+	}
+	dataPackagePath, err := store.SaveDataPackage(ctx, req.Resolved, dataPackage)
+	if err != nil {
+		return nil, err
+	}
+	metadata.DataPackagePath = dataPackagePath
+
+	renderer := req.Renderer
+	if renderer == nil {
+		renderer = scriptorium.Runner{
+			Binary:     req.Config.Scriptorium.Binary,
+			ConfigPath: req.Config.Scriptorium.ConfigPath,
+			Profile:    req.Config.Scriptorium.Profile,
+			Timeout:    req.Config.Scriptorium.Timeout,
+			ExtraArgs:  req.Config.Scriptorium.ExtraArgs,
+		}
+	}
+	renderResult, renderErr := renderer.Render(ctx, scriptorium.RenderRequest{
+		PromptID:        req.Resolved.Definition.PromptID,
+		DataPackagePath: dataPackagePath,
+	})
+
+	preflightPath := paths.Preflight
+	if renderResult != nil {
+		var err error
+		preflightPath, err = store.SavePreflight(ctx, req.Resolved, preflightArtifact(renderResult))
+		if err != nil {
+			return nil, err
+		}
+	}
+	metadata.PreflightPath = preflightPath
+	metadataPath, metadataErr := store.SaveMetadata(ctx, metadata)
+	if metadataErr != nil {
+		return nil, metadataErr
+	}
+	if renderErr != nil {
+		return nil, renderErr
+	}
+
+	reportPath, err := store.PrepareRenderedReport(ctx, req.Resolved)
+	if err != nil {
+		return nil, err
+	}
+	runResult, runErr := renderer.Run(ctx, scriptorium.RunRequest{
+		PromptID:        req.Resolved.Definition.PromptID,
+		DataPackagePath: dataPackagePath,
+		OutputPath:      reportPath,
+	})
+	if runErr == nil && req.OutputPath != "" && req.OutputPath != reportPath {
+		if err := fileutil.CopyFileAtomic(reportPath, req.OutputPath); err != nil {
+			return nil, err
+		}
+	}
+	outputPath := reportPath
+	if req.OutputPath != "" {
+		outputPath = req.OutputPath
+	}
+	metadata.RenderedReportPath = reportPath
+	metadataPath, metadataErr = store.SaveMetadata(ctx, metadata)
+	if metadataErr != nil {
+		return nil, metadataErr
+	}
+	if runErr != nil {
+		return nil, runErr
+	}
+
+	notification, notificationPath, err := notifyReport(ctx, req.Config, req.Resolved, reportPath, metadata, req.Notifier, store)
+	if notificationPath != "" {
+		metadata.NotificationPath = notificationPath
+		metadataPath, metadataErr = store.SaveMetadata(ctx, metadata)
+		if metadataErr != nil {
+			return nil, metadataErr
+		}
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return &ReportResult{
+		ModuleSnapshot:     moduleSnapshot,
+		ModuleSnapshotPath: moduleSnapshotPath,
+		DataPackage:        dataPackage,
+		DataPackagePath:    dataPackagePath,
+		PreflightPath:      preflightPath,
+		ReportPath:         reportPath,
+		OutputPath:         outputPath,
+		NotificationPath:   notificationPath,
+		Metadata:           metadata,
+		MetadataPath:       metadataPath,
+		PriorSnapshot:      priorSnapshot,
+		RecentChanges:      recentChanges,
+		RenderResult:       renderResult,
+		RunResult:          runResult,
+		Notification:       notification,
+	}, nil
+}
+
+func notifyReport(ctx context.Context, cfg config.Config, resolved report.Resolved, reportPath string, metadata state.Metadata, notifier Notifier, store state.Store) (*NotificationResult, string, error) {
+	notifier, enabled := reportNotifier(cfg, notifier)
+	if !enabled {
+		return nil, "", nil
+	}
+	notificationRequest, err := buildNotificationRequest(cfg, resolved, reportPath, metadata)
+	if err != nil {
+		notificationPath, saveErr := saveNotificationArtifact(ctx, store, resolved, cfg, metadata, NotificationRequest{}, nil, err)
+		if saveErr != nil {
+			return nil, "", saveErr
+		}
+		return nil, notificationPath, err
+	}
+	result, err := notifier.Notify(ctx, notificationRequest)
+	notificationPath, saveErr := saveNotificationArtifact(ctx, store, resolved, cfg, metadata, notificationRequest, result, err)
+	if saveErr != nil {
+		return nil, "", saveErr
+	}
+	if err != nil {
+		return result, notificationPath, &NotificationError{
+			Request: notificationRequest,
+			Err:     fmt.Errorf("notify report %q run %q from managed report %q: %w", resolved.Definition.ID, metadata.RunID, reportPath, err),
+		}
+	}
+	return result, notificationPath, nil
+}
+
+func reportNotifier(cfg config.Config, notifier Notifier) (Notifier, bool) {
+	if !cfg.Notify.Distributor.Enabled {
+		return noopNotifier{}, false
+	}
+	if notifier != nil {
+		return notifier, true
+	}
+	return distributorNotifier{
+		client: distributoradapter.New(cfg.Notify.Distributor),
+	}, true
+}
+
+func buildNotificationRequest(cfg config.Config, resolved report.Resolved, reportPath string, metadata state.Metadata) (NotificationRequest, error) {
+	values := config.DistributorTemplateValues{
+		LocationID:      cfg.Location.ID,
+		ReportID:        string(resolved.Definition.ID),
+		RunID:           metadata.RunID,
+		ArtifactGroup:   resolved.Definition.ArtifactGroup,
+		BatchOutputName: resolved.Definition.BatchOutputName,
+	}
+	if err := addDistributorValidPeriodValues(&values, resolved.ValidPeriod, cfg.WeatherAPI.Timezone); err != nil {
+		return NotificationRequest{}, err
+	}
+	bundleID, err := config.RenderDistributorBundleID(cfg.Notify.Distributor.BundleIDTemplate, values)
+	if err != nil {
+		return NotificationRequest{}, err
+	}
+	values.BundleID = bundleID
+	pipelineID, err := config.RenderDistributorPipelineID(cfg.Notify.Distributor.PipelineIDTemplate, values)
+	if err != nil {
+		return NotificationRequest{}, err
+	}
+	idempotencyKey, err := config.RenderDistributorIdempotencyKey(cfg.Notify.Distributor.IdempotencyKeyTemplate, values)
+	if err != nil {
+		return NotificationRequest{}, err
+	}
+	bundlePaths, err := config.RenderDistributorReportPaths(cfg.Notify.Distributor.ReportPathTemplates, values)
+	if err != nil {
+		return NotificationRequest{}, err
+	}
+	return NotificationRequest{
+		ReportID:       resolved.Definition.ID,
+		RunID:          metadata.RunID,
+		PipelineID:     pipelineID,
+		BundleID:       bundleID,
+		IdempotencyKey: idempotencyKey,
+		ReportPath:     reportPath,
+		BundlePaths:    bundlePaths,
+		CreatedAt:      metadata.GeneratedAt,
+	}, nil
+}
+
+func addDistributorValidPeriodValues(values *config.DistributorTemplateValues, period timeutil.Period, timezone string) error {
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		return err
+	}
+	start := period.Start.In(location)
+	end := period.End.In(location)
+	values.ValidStartDate = start.Format(timeutil.DateLayout)
+	values.ValidEndDate = end.Format(timeutil.DateLayout)
+	values.ValidStartTime = start.Format("1504")
+	values.ValidEndTime = end.Format("1504")
+	values.ValidStartStamp = start.Format("2006-01-02T1504")
+	values.ValidEndStamp = end.Format("2006-01-02T1504")
+	return nil
+}
+
+func saveNotificationArtifact(ctx context.Context, store state.Store, resolved report.Resolved, cfg config.Config, metadata state.Metadata, req NotificationRequest, result *NotificationResult, notifyErr error) (string, error) {
+	if store == nil {
+		return "", fmt.Errorf("state store is required")
+	}
+	artifact := state.DistributorNotificationArtifact{
+		SchemaVersion:  state.DistributorNotificationSchemaVersion,
+		RunID:          metadata.RunID,
+		ReportID:       resolved.Definition.ID,
+		AttemptedAt:    time.Now(),
+		Endpoint:       cfg.Notify.Distributor.Endpoint,
+		PipelineID:     req.PipelineID,
+		BundleID:       req.BundleID,
+		IdempotencyKey: req.IdempotencyKey,
+		SourcePath:     req.ReportPath,
+		BundlePaths:    append([]string(nil), req.BundlePaths...),
+		BundleCreated:  req.CreatedAt,
+		Status:         "attempted",
+	}
+	if result != nil {
+		artifact.Status = result.Status
+		artifact.Upload = &state.DistributorUploadResult{
+			RunID:  result.RunID,
+			Status: result.UploadStatus,
+		}
+		if result.PipelineID != "" || !result.AcceptedAt.IsZero() || result.StartedAt != nil || result.FinishedAt != nil || len(result.Report) > 0 || result.Error != "" {
+			artifact.RunStatus = &state.DistributorRunStatus{
+				RunID:      result.RunID,
+				PipelineID: result.PipelineID,
+				Status:     result.Status,
+				AcceptedAt: result.AcceptedAt,
+				StartedAt:  result.StartedAt,
+				FinishedAt: result.FinishedAt,
+				Report:     append([]byte(nil), result.Report...),
+				Error:      result.Error,
+			}
+		}
+		artifact.StatusError = result.StatusError
+	}
+	if notifyErr != nil {
+		artifact.Status = "failed"
+		artifact.Error = notifyErr.Error()
+	}
+	if artifact.Status == "" {
+		artifact.Status = "unknown"
+	}
+	return store.SaveDistributorNotification(ctx, resolved, artifact)
+}
+
+type noopNotifier struct{}
+
+func (noopNotifier) Notify(context.Context, NotificationRequest) (*NotificationResult, error) {
+	return nil, nil
+}
+
+type distributorNotifier struct {
+	client *distributoradapter.Client
+}
+
+func (n distributorNotifier) Notify(ctx context.Context, req NotificationRequest) (*NotificationResult, error) {
+	result, err := n.client.Upload(ctx, distributoradapter.UploadRequest{
+		PipelineID:     req.PipelineID,
+		BundleID:       req.BundleID,
+		IdempotencyKey: req.IdempotencyKey,
+		Files:          distributorUploadFiles(req.ReportPath, req.BundlePaths),
+		CreatedAt:      req.CreatedAt,
+	})
+	notification := &NotificationResult{
+		PipelineID:     req.PipelineID,
+		BundleID:       req.BundleID,
+		IdempotencyKey: req.IdempotencyKey,
+		RunID:          result.RunID,
+		Status:         result.Status,
+		UploadStatus:   result.UploadStatus,
+		StatusError:    result.StatusError,
+	}
+	if result.RunStatus != nil {
+		if result.RunStatus.PipelineID != "" {
+			notification.PipelineID = result.RunStatus.PipelineID
+		}
+		notification.AcceptedAt = result.RunStatus.AcceptedAt
+		notification.StartedAt = result.RunStatus.StartedAt
+		notification.FinishedAt = result.RunStatus.FinishedAt
+		notification.Report = append([]byte(nil), result.RunStatus.Report...)
+		notification.Error = result.RunStatus.Error
+	}
+	if err != nil {
+		return notification, err
+	}
+	return notification, nil
+}
+
+func distributorUploadFiles(sourcePath string, bundlePaths []string) []distributoradapter.UploadFile {
+	files := make([]distributoradapter.UploadFile, 0, len(bundlePaths))
+	for _, bundlePath := range bundlePaths {
+		files = append(files, distributoradapter.UploadFile{
+			SourcePath: sourcePath,
+			BundlePath: bundlePath,
+		})
+	}
+	return files
+}
+
+func BuildModuleSnapshot(req ModuleSnapshotRequest, bundle *weatherdata.Bundle) (module.Snapshot, error) {
+	reportFacts, err := BuildReportFacts(req, bundle)
+	if err != nil {
+		return module.Snapshot{}, err
+	}
+	return BuildModuleSnapshotFromFacts(req, reportFacts)
+}
+
+func BuildReportFacts(req ModuleSnapshotRequest, bundle *weatherdata.Bundle) (ReportFacts, error) {
+	collected := facts.BuildCollected(bundle)
+	derived, err := buildDerivedFacts(req.Config, req.Resolved, collected)
+	if err != nil {
+		return ReportFacts{}, err
+	}
+	return ReportFacts{
+		Collected: collected,
+		Derived:   derived,
+	}, nil
+}
+
+func BuildModuleSnapshotFromFacts(req ModuleSnapshotRequest, reportFacts ReportFacts) (module.Snapshot, error) {
+	if !req.Resolved.ValidPeriod.IsValid() {
+		return module.Snapshot{}, fmt.Errorf("resolved valid period is required")
+	}
+	registry, err := briefing.DefaultModuleRegistry()
+	if err != nil {
+		return module.Snapshot{}, err
+	}
+	moduleContext := briefing.ModuleContext{
+		Resolved:  req.Resolved,
+		Collected: reportFacts.Collected,
+		Derived:   reportFacts.Derived,
+		Units:     req.Config.WeatherAPI.Units,
+		Timezone:  req.Config.WeatherAPI.Timezone,
+		Location:  briefingLocation(req.Config),
+	}
+	var outputs []module.Output
+	for _, item := range req.Resolved.Definition.Modules {
+		output, err := registry.BuildModule(moduleContext, item)
+		if err != nil {
+			return module.Snapshot{}, err
+		}
+		if output == nil {
+			continue
+		}
+		outputs = append(outputs, *output)
+	}
+	return module.NewSnapshot(outputs)
+}
+
+func briefingBuildContext(cfg config.Config, resolved report.Resolved, collected facts.CollectedFacts) briefing.BuildContext {
+	return briefing.BuildContext{
+		Resolved: resolved,
+		Bundle:   collected.Bundle(),
+		Units:    cfg.WeatherAPI.Units,
+		Timezone: cfg.WeatherAPI.Timezone,
+		Location: briefingLocation(cfg),
+	}
+}
+
+func promptMetadata(metadata state.Metadata) promptinput.Metadata {
+	return promptinput.Metadata{
+		RunID:          metadata.RunID,
+		ReportID:       metadata.ReportID,
+		Variant:        metadata.Variant,
+		PromptID:       metadata.PromptID,
+		GeneratedAt:    metadata.GeneratedAt,
+		Timezone:       metadata.Timezone,
+		ValidPeriod:    metadata.ValidPeriod,
+		SourceWarnings: metadata.SourceWarnings,
+	}
+}
+
+func buildDerivedFacts(cfg config.Config, resolved report.Resolved, collected facts.CollectedFacts) (facts.DerivedFacts, error) {
+	dayparts := make([]forecast.DaypartDefinition, 0, len(cfg.Dayparts))
+	for _, daypart := range cfg.Dayparts {
+		dayparts = append(dayparts, forecast.DaypartDefinition{
+			Name:  daypart.Name,
+			Start: daypart.Start,
+			End:   daypart.End,
+		})
+	}
+	return facts.BuildDerived(facts.BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  cfg.WeatherAPI.Timezone,
+		Dayparts:  dayparts,
+		Collected: collected,
+	})
+}
+
+func briefingLocation(cfg config.Config) *briefing.LocationContext {
+	location := briefing.LocationContext{
+		ID:       cfg.Location.ID,
+		Name:     cfg.Location.Name,
+		Region:   cfg.Location.Region,
+		Timezone: cfg.WeatherAPI.Timezone,
+	}
+	if location.ID == "" && location.Name == "" && location.Region == "" && location.Timezone == "" {
+		return nil
+	}
+	return &location
+}
+
+func defaultStore(cfg config.Config) (*state.FilesystemStore, error) {
+	return state.NewFilesystemStore(cfg.Workspace)
+}
+
+func recentChanges(ctx context.Context, store state.Store, priorSnapshot *state.PriorSnapshot, reportID report.ID, current module.Snapshot, cfg config.RecentChangeConfig) ([]changes.Change, error) {
+	if priorSnapshot == nil {
+		return nil, nil
+	}
+	previous, err := store.LoadModuleSnapshot(ctx, priorSnapshot.ModuleSnapshotPath)
+	if err != nil {
+		return nil, err
+	}
+	thresholds := changes.Thresholds{
+		TemperatureDegrees:       cfg.TemperatureDegrees,
+		PrecipProbabilityPoints:  cfg.PrecipProbabilityPoints,
+		WindGustMilesPerHour:     cfg.WindGustMilesPerHour,
+		PrecipTimingShiftMinutes: cfg.PrecipTimingShiftMinutes,
+	}
+	switch reportID {
+	case report.DailyToday, report.DailyTomorrow:
+		return changes.CompareDaily(previous, current, thresholds)
+	case report.ThreeDay:
+		return changes.CompareThreeDay(previous, current, thresholds)
+	case report.Weekend:
+		return changes.CompareWeekend(previous, current, thresholds)
+	default:
+		return nil, nil
+	}
+}
+
+func preflightArtifact(result *scriptorium.RenderResult) state.PreflightArtifact {
+	if result == nil {
+		return state.PreflightArtifact{}
+	}
+	return state.PreflightArtifact{
+		Command:         append([]string(nil), result.Command...),
+		Stdout:          result.Stdout,
+		Stderr:          result.Stderr,
+		StdoutTruncated: result.StdoutTruncated,
+		StderrTruncated: result.StderrTruncated,
+		ExitCode:        result.ExitCode,
+	}
+}

internal/app/inspect.go

@@ -0,0 +1,126 @@
+package app
+
+import (
+	"context"
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/briefing"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/promptinput"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/state"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type InspectReportsRequest struct {
+	Config config.Config
+	Limit  int
+}
+
+type InspectRunRequest struct {
+	Config config.Config
+	RunID  string
+}
+
+type SourceInspection struct {
+	RunID          string                      `json:"runId"`
+	ReportID       report.ID                   `json:"reportId"`
+	SourceLocation string                      `json:"sourceLocation,omitempty"`
+	Sources        []briefing.SourceMetadata   `json:"sources,omitempty"`
+	Warnings       []weatherdata.SourceWarning `json:"warnings,omitempty"`
+}
+
+func InspectReports(ctx context.Context, req InspectReportsRequest) ([]state.ReportRecord, error) {
+	store, err := defaultStore(req.Config)
+	if err != nil {
+		return nil, err
+	}
+	return store.ListReports(ctx, req.Limit)
+}
+
+func InspectMetadata(ctx context.Context, req InspectRunRequest) (state.Metadata, error) {
+	inspection, err := inspectRun(ctx, req)
+	return inspection.metadata, err
+}
+
+func InspectModules(ctx context.Context, req InspectRunRequest) (module.Snapshot, error) {
+	inspection, err := inspectRun(ctx, req)
+	if err != nil {
+		return module.Snapshot{}, err
+	}
+	return inspection.store.LoadModuleSnapshot(ctx, inspection.metadata.ModuleSnapshotPath)
+}
+
+func InspectDataPackage(ctx context.Context, req InspectRunRequest) (promptinput.Package, error) {
+	inspection, err := inspectRun(ctx, req)
+	if err != nil {
+		return promptinput.Package{}, err
+	}
+	return inspection.store.LoadDataPackage(ctx, inspection.metadata.DataPackagePath)
+}
+
+func InspectPriorSnapshot(ctx context.Context, req InspectRunRequest) (*state.PriorSnapshot, error) {
+	inspection, err := inspectRun(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+	resolved, err := resolvedFromMetadata(inspection.metadata)
+	if err != nil {
+		return nil, err
+	}
+	return inspection.store.FindPriorSnapshot(ctx, resolved)
+}
+
+func InspectSources(ctx context.Context, req InspectRunRequest) (SourceInspection, error) {
+	inspection, err := inspectRun(ctx, req)
+	if err != nil {
+		return SourceInspection{}, err
+	}
+	metadata := inspection.metadata
+	return SourceInspection{
+		RunID:          metadata.RunID,
+		ReportID:       metadata.ReportID,
+		SourceLocation: metadata.SourceLocation,
+		Sources:        metadata.Sources,
+		Warnings:       metadata.SourceWarnings,
+	}, nil
+}
+
+type runInspection struct {
+	store    *state.FilesystemStore
+	metadata state.Metadata
+}
+
+func inspectRun(ctx context.Context, req InspectRunRequest) (runInspection, error) {
+	store, err := defaultStore(req.Config)
+	if err != nil {
+		return runInspection{}, err
+	}
+	metadata, _, err := store.LoadMetadataByRunID(ctx, req.RunID)
+	if err != nil {
+		return runInspection{}, err
+	}
+	return runInspection{store: store, metadata: metadata}, nil
+}
+
+func resolvedFromMetadata(metadata state.Metadata) (report.Resolved, error) {
+	definition, err := report.DefaultRegistry().Lookup(metadata.ReportID)
+	if err != nil {
+		return report.Resolved{}, err
+	}
+	location, err := timeutil.LoadLocation(metadata.Timezone)
+	if err != nil {
+		return report.Resolved{}, err
+	}
+	if !metadata.ValidPeriod.IsValid() {
+		return report.Resolved{}, fmt.Errorf("metadata valid period for run id %q is invalid", metadata.RunID)
+	}
+	return report.Resolved{
+		Definition:  definition,
+		GeneratedAt: metadata.GeneratedAt,
+		Timezone:    location.String(),
+		ValidPeriod: metadata.ValidPeriod,
+	}, nil
+}

internal/briefing/alert_digest_module.go

@@ -0,0 +1,60 @@
+package briefing
+
+import (
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type AlertDigestModule struct {
+	Checked       bool           `json:"checked"`
+	ActiveCount   int            `json:"active_count"`
+	RelevantCount int            `json:"relevant_count"`
+	Missing       bool           `json:"missing,omitempty"`
+	Relevant      []AlertSummary `json:"relevant,omitempty"`
+}
+
+type AlertSummary struct {
+	Event    string `json:"event,omitempty"`
+	Headline string `json:"headline,omitempty"`
+	Severity string `json:"severity,omitempty"`
+}
+
+func buildAlertDigestModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	value := alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps)
+	if value == nil {
+		value = &AlertDigestModule{}
+	}
+	return &module.Output{ID: module.AlertDigest, StanzaName: "alert_digest", Value: *value}, nil
+}
+
+func alertDigest(collected facts.CollectedFacts, overlaps []forecast.AlertOverlap) *AlertDigestModule {
+	missing := sourceMissing(collected.SourceProvenance, "alerts")
+	if collected.Alerts == nil && !missing {
+		return nil
+	}
+	value := &AlertDigestModule{Missing: missing}
+	if collected.Alerts != nil {
+		value.Checked = true
+		value.ActiveCount = len(collected.Alerts.Alerts)
+	}
+	value.RelevantCount = len(overlaps)
+	for _, overlap := range overlaps {
+		value.Relevant = append(value.Relevant, AlertSummary{
+			Event:    overlap.Event,
+			Headline: overlap.Headline,
+			Severity: overlap.Severity,
+		})
+	}
+	return value
+}
+
+func sourceMissing(sources []weatherdata.Source, name string) bool {
+	for _, source := range sources {
+		if source.Name == name && source.Missing {
+			return true
+		}
+	}
+	return false
+}

internal/briefing/area_forecast_discussion_module.go

@@ -0,0 +1,67 @@
+package briefing
+
+import (
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+type AreaForecastDiscussionModule struct {
+	Product     string   `json:"product,omitempty"`
+	KeyMessages []string `json:"key_messages,omitempty"`
+	ShortTerm   string   `json:"short_term,omitempty"`
+	LongTerm    string   `json:"long_term,omitempty"`
+}
+
+func buildAreaForecastDiscussionModule(ctx ModuleContext, options any) (*module.Output, error) {
+	discussion := ctx.Collected.Discussion
+	if discussion == nil {
+		return nil, nil
+	}
+	opts, ok := options.(module.AreaForecastDiscussionOptions)
+	if !ok {
+		return nil, fmt.Errorf("area forecast discussion options have type %T", options)
+	}
+	sections, err := areaForecastDiscussionSections(opts)
+	if err != nil {
+		return nil, err
+	}
+	value := AreaForecastDiscussionModule{}
+	if sections["product"] {
+		value.Product = discussion.Product
+	}
+	if sections["key_messages"] {
+		value.KeyMessages = append([]string(nil), discussion.KeyMessages...)
+	}
+	if sections["short_term"] && discussion.ShortTerm != nil {
+		value.ShortTerm = discussion.ShortTerm.Text
+	}
+	if sections["long_term"] && discussion.LongTerm != nil {
+		value.LongTerm = discussion.LongTerm.Text
+	}
+	if value.Product == "" && len(value.KeyMessages) == 0 && value.ShortTerm == "" && value.LongTerm == "" {
+		return nil, nil
+	}
+	return &module.Output{ID: module.AreaForecastDiscussion, StanzaName: "area_forecast_discussion", Value: value}, nil
+}
+
+func areaForecastDiscussionSections(options module.AreaForecastDiscussionOptions) (map[string]bool, error) {
+	if len(options.Sections) == 0 {
+		return map[string]bool{
+			"product":      true,
+			"key_messages": true,
+			"short_term":   true,
+			"long_term":    true,
+		}, nil
+	}
+	sections := map[string]bool{}
+	for _, section := range options.Sections {
+		switch section {
+		case "product", "key_messages", "short_term", "long_term":
+			sections[section] = true
+		default:
+			return nil, fmt.Errorf("area forecast discussion section %q is not supported", section)
+		}
+	}
+	return sections, nil
+}

internal/briefing/base_modules_test.go

@@ -0,0 +1,493 @@
+package briefing
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+func TestBaseModulesBuildAvailableSourceOutputs(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	tests := []struct {
+		id     module.ID
+		stanza string
+	}{
+		{id: module.Metadata, stanza: "metadata"},
+		{id: module.CurrentConditions, stanza: "current_conditions"},
+		{id: module.NarrativeForecast, stanza: "narrative_forecast"},
+		{id: module.HourlyForecast, stanza: "hourly_forecast"},
+		{id: module.AlertDigest, stanza: "alert_digest"},
+		{id: module.AreaForecastDiscussion, stanza: "area_forecast_discussion"},
+		{id: module.WeatherStory, stanza: "weather_story"},
+	}
+	for _, tt := range tests {
+		t.Run(string(tt.id), func(t *testing.T) {
+			output, err := registry.BuildModule(ctx, module.ConfigItem{ID: tt.id})
+			if err != nil {
+				t.Fatalf("BuildModule() error = %v", err)
+			}
+			if output == nil {
+				t.Fatal("BuildModule() output = nil, want stanza")
+			}
+			if output.ID != tt.id || output.StanzaName != tt.stanza {
+				t.Fatalf("output = %#v, want id %q stanza %q", output, tt.id, tt.stanza)
+			}
+		})
+	}
+}
+
+func TestHourlyForecastModuleUsesValidPeriodHourlyPeriods(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.HourlyForecast})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[HourlyForecastModule](t, output)
+	if value.Product != "hourly" || value.SourceLocationID != "test-grid" || len(value.Periods) != 1 {
+		t.Fatalf("HourlyForecast = %#v, want hourly metadata and one valid-period period", value)
+	}
+	period := value.Periods[0]
+	if period.TextDescription != "Showers likely." || period.TemperatureF == nil || *period.TemperatureF != 76 {
+		t.Fatalf("HourlyForecast period = %#v, want hourly period facts", period)
+	}
+	if period.StartTime != "2026-05-29 at 8:00 AM" || period.EndTime != "2026-05-29 at 9:00 AM" {
+		t.Fatalf("HourlyForecast period times = %q/%q, want friendly local time labels", period.StartTime, period.EndTime)
+	}
+	if period.WindDirection != "S" || period.ProbabilityOfPrecipitationPercent == nil || *period.ProbabilityOfPrecipitationPercent != 70 {
+		t.Fatalf("HourlyForecast period = %#v, want compass wind and precip chance", period)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("Marshal hourly forecast: %v", err)
+	}
+	jsonText := string(data)
+	for _, field := range []string{"source_location_id", "text_description", "temperature_f", "wind_direction", "probability_of_precipitation_percent", "relative_humidity_percent"} {
+		if !strings.Contains(jsonText, field) {
+			t.Fatalf("hourly json = %s, want field %s", jsonText, field)
+		}
+	}
+	if strings.Contains(jsonText, "wind_direction_degrees") || strings.Contains(jsonText, "Tomorrow") {
+		t.Fatalf("hourly json = %s, want valid-period prompt fields only", jsonText)
+	}
+	if strings.Contains(jsonText, `"start_time":"2026-05-29T`) || strings.Contains(jsonText, `"end_time":"2026-05-29T`) {
+		t.Fatalf("hourly json = %s, want friendly local start/end times", jsonText)
+	}
+}
+
+func TestHourlyForecastModuleRejectsUnsupportedReports(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+	ctx.Resolved.Definition = report.DefaultRegistry().MustLookup(report.Weekend)
+
+	_, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.HourlyForecast})
+	if err == nil || !strings.Contains(err.Error(), `module "hourly_forecast" is not compatible with report "weekend"`) {
+		t.Fatalf("BuildModule() error = %v, want incompatible report", err)
+	}
+}
+
+func TestNarrativeForecastModuleUsesValidPeriodNarrativePeriods(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.NarrativeForecast})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[NarrativeForecastModule](t, output)
+	if value.Product != "narrative" || value.SourceLocationID != "test-grid" || len(value.Periods) != 1 {
+		t.Fatalf("NarrativeForecast = %#v, want narrative metadata and one valid-period period", value)
+	}
+	period := value.Periods[0]
+	if period.Name != "Today" || period.TextDescription != "Morning storms, then partly sunny." {
+		t.Fatalf("NarrativeForecast period = %#v, want Today narrative", period)
+	}
+	if period.StartTime != "2026-05-29 at 6:00 AM" || period.EndTime != "2026-05-29 at 6:00 PM" {
+		t.Fatalf("NarrativeForecast period times = %q/%q, want friendly local time labels", period.StartTime, period.EndTime)
+	}
+	if period.IsDay == nil || !*period.IsDay || period.TemperatureF == nil || *period.TemperatureF != 81 || period.ProbabilityOfPrecipitationPercent == nil || *period.ProbabilityOfPrecipitationPercent != 60 {
+		t.Fatalf("NarrativeForecast period = %#v, want day, temperature, and precip values", period)
+	}
+	if period.WindDirection != "NE" {
+		t.Fatalf("NarrativeForecast period wind direction = %q, want NE", period.WindDirection)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("Marshal narrative forecast: %v", err)
+	}
+	jsonText := string(data)
+	for _, field := range []string{"source_location_id", "text_description", "temperature_f", "wind_speed_mph", "wind_direction", "probability_of_precipitation_percent"} {
+		if !strings.Contains(jsonText, field) {
+			t.Fatalf("narrative json = %s, want field %s", jsonText, field)
+		}
+	}
+	if strings.Contains(jsonText, "wind_direction_degrees") {
+		t.Fatalf("narrative json = %s, want compass wind_direction without degrees field", jsonText)
+	}
+	if strings.Contains(jsonText, `"start_time":"2026-05-29T`) || strings.Contains(jsonText, `"end_time":"2026-05-29T`) {
+		t.Fatalf("narrative json = %s, want friendly local start/end times", jsonText)
+	}
+	if strings.Contains(jsonText, "Tomorrow night") {
+		t.Fatalf("narrative json = %s, want only valid-period narrative periods", jsonText)
+	}
+}
+
+func TestNarrativeForecastModuleRejectsUnsupportedReports(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+	ctx.Resolved.Definition = report.DefaultRegistry().MustLookup(report.Weekend)
+
+	_, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.NarrativeForecast})
+	if err == nil || !strings.Contains(err.Error(), `module "narrative_forecast" is not compatible with report "weekend"`) {
+		t.Fatalf("BuildModule() error = %v, want incompatible report", err)
+	}
+}
+
+func TestMetadataModuleUsesPromptSafeSourceWarningSummary(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.Metadata})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[MetadataModule](t, output)
+	if value.RunID == "" || value.ReportID != report.DailyToday || value.PromptID != "weather.daily_report" {
+		t.Fatalf("metadata = %#v, want report identity", value)
+	}
+	if value.Location == nil || value.Location.Name != "Brentwood" {
+		t.Fatalf("Location = %#v, want configured location", value.Location)
+	}
+	if len(value.SourceWarnings) != 1 || value.SourceWarnings[0].CompletenessImpact != "source omitted" {
+		t.Fatalf("SourceWarnings = %#v, want warning summary", value.SourceWarnings)
+	}
+	if value.Alerts == nil || !value.Alerts.Checked || value.Alerts.ActiveCount != 1 || value.Alerts.RelevantCount != 1 {
+		t.Fatalf("Alerts = %#v, want checked alert status", value.Alerts)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("Marshal metadata: %v", err)
+	}
+	jsonText := string(data)
+	if !strings.Contains(jsonText, "source_warnings") || strings.Contains(jsonText, "endpoint") || strings.Contains(jsonText, "dataSha256") {
+		t.Fatalf("metadata json = %s, want source warning summary without transport provenance", jsonText)
+	}
+}
+
+func TestCurrentConditionsModuleUsesSnakeCaseUnitFields(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.CurrentConditions})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[CurrentConditionsModule](t, output)
+	if value.ConditionText != "Partly cloudy" || value.TemperatureF == nil || *value.TemperatureF != 74 {
+		t.Fatalf("CurrentConditions = %#v, want current condition facts", value)
+	}
+	if value.WindDirection != "S" {
+		t.Fatalf("WindDirection = %q, want S", value.WindDirection)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("Marshal current conditions: %v", err)
+	}
+	jsonText := string(data)
+	for _, field := range []string{"condition_text", "temperature_f", "apparent_temperature_f", "relative_humidity_percent", "wind_speed_mph", "wind_direction"} {
+		if !strings.Contains(jsonText, field) {
+			t.Fatalf("current json = %s, want field %s", jsonText, field)
+		}
+	}
+	if strings.Contains(jsonText, "wind_direction_degrees") {
+		t.Fatalf("current json = %s, want compass wind_direction without degrees field", jsonText)
+	}
+}
+
+func TestAlertDigestDistinguishesCheckedEmptyAndMissing(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+	ctx.Collected.Alerts = &weatherdata.AlertRun{}
+	ctx.Derived.AlertOverlaps = nil
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.AlertDigest})
+	if err != nil {
+		t.Fatalf("BuildModule(checked empty) error = %v", err)
+	}
+	checked := moduleValue[AlertDigestModule](t, output)
+	if !checked.Checked || checked.ActiveCount != 0 || checked.RelevantCount != 0 || checked.Missing {
+		t.Fatalf("checked empty alert digest = %#v, want checked/no active", checked)
+	}
+
+	ctx.Collected.Alerts = nil
+	ctx.Collected.SourceProvenance = []weatherdata.Source{{Name: "alerts", Missing: true}}
+	output, err = registry.BuildModule(ctx, module.ConfigItem{ID: module.AlertDigest})
+	if err != nil {
+		t.Fatalf("BuildModule(missing) error = %v", err)
+	}
+	missing := moduleValue[AlertDigestModule](t, output)
+	if missing.Checked || !missing.Missing {
+		t.Fatalf("missing alert digest = %#v, want missing unchecked source", missing)
+	}
+}
+
+func TestBaseModulesOmitMissingOptionalOutputs(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+	ctx.Collected.Current = nil
+	ctx.Collected.Narrative = nil
+	ctx.Collected.Hourly = nil
+	ctx.Derived.ValidPeriodNarrativePeriods = nil
+	ctx.Derived.ValidPeriodHourlyPeriods = nil
+	ctx.Collected.Discussion = nil
+	ctx.Collected.WeatherStory = nil
+
+	for _, id := range []module.ID{module.CurrentConditions, module.NarrativeForecast, module.HourlyForecast, module.AreaForecastDiscussion, module.WeatherStory} {
+		output, err := registry.BuildModule(ctx, module.ConfigItem{ID: id})
+		if err != nil {
+			t.Fatalf("BuildModule(%s) error = %v", id, err)
+		}
+		if output != nil {
+			t.Fatalf("BuildModule(%s) output = %#v, want omitted", id, output)
+		}
+	}
+}
+
+func TestAreaForecastDiscussionAndWeatherStoryModules(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	afdOutput, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.AreaForecastDiscussion})
+	if err != nil {
+		t.Fatalf("BuildModule(afd) error = %v", err)
+	}
+	afd := moduleValue[AreaForecastDiscussionModule](t, afdOutput)
+	if len(afd.KeyMessages) != 1 || afd.ShortTerm != "Showers increase this afternoon." || afd.LongTerm != "Periodic rain chances continue." {
+		t.Fatalf("AFD = %#v, want discussion sections", afd)
+	}
+
+	storyOutput, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.WeatherStory})
+	if err != nil {
+		t.Fatalf("BuildModule(weather story) error = %v", err)
+	}
+	story := moduleValue[WeatherStoryModule](t, storyOutput)
+	if !story.Available || story.Title != "Rain Chances" || story.Description != "Scattered showers are possible." {
+		t.Fatalf("WeatherStory = %#v, want structured story fields", story)
+	}
+	data, err := json.Marshal(storyOutput.Value)
+	if err != nil {
+		t.Fatalf("Marshal weather story: %v", err)
+	}
+	if !strings.Contains(string(data), "download_url") {
+		t.Fatalf("weather story json = %s, want snake_case download_url", string(data))
+	}
+}
+
+func TestAreaForecastDiscussionModuleCanSelectSections(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{
+		ID:      module.AreaForecastDiscussion,
+		Options: module.AreaForecastDiscussionOptions{Sections: []string{"short_term"}},
+	})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	afd := moduleValue[AreaForecastDiscussionModule](t, output)
+	if afd.ShortTerm != "Showers increase this afternoon." {
+		t.Fatalf("ShortTerm = %q, want selected short term section", afd.ShortTerm)
+	}
+	if afd.Product != "" || len(afd.KeyMessages) != 0 || afd.LongTerm != "" {
+		t.Fatalf("AFD = %#v, want only short_term section", afd)
+	}
+}
+
+func testModuleContext() ModuleContext {
+	generatedAt := mustParseModuleTime("2026-05-29T08:00:00-05:00")
+	definition := report.DefaultRegistry().MustLookup(report.DailyToday)
+	resolved := report.Resolved{
+		Definition:  definition,
+		GeneratedAt: generatedAt,
+		Timezone:    "America/Chicago",
+		ValidPeriod: timeutil.Period{
+			Start: mustParseModuleTime("2026-05-29T00:00:00-05:00"),
+			End:   mustParseModuleTime("2026-05-30T00:00:00-05:00"),
+		},
+	}
+	isDay := true
+	tempF := 74.0
+	apparentF := 76.0
+	humidity := 71.0
+	windMph := 8.0
+	windDirection := 190.0
+	narrativeTempF := 81.0
+	narrativePop := 60.0
+	narrativeWind := 12.0
+	narrativeWindDirection := 45.0
+	hourlyTempF := 76.0
+	hourlyPop := 70.0
+	hourlyHumidity := 66.0
+	hourlyWindMph := 14.0
+	updatedAt := mustParseModuleTime("2026-05-29T07:30:00-05:00")
+	return ModuleContext{
+		Resolved: resolved,
+		Collected: facts.CollectedFacts{
+			Current: &weatherdata.Current{
+				ConditionText:           "Partly cloudy",
+				IsDay:                   &isDay,
+				TemperatureF:            &tempF,
+				ApparentTemperatureF:    &apparentF,
+				RelativeHumidityPercent: &humidity,
+				WindSpeedMph:            &windMph,
+				WindDirectionDegrees:    &windDirection,
+			},
+			Narrative: &weatherdata.ForecastRun{
+				LocationID:   "test-grid",
+				LocationName: "Testville",
+				IssuedAt:     mustParseModuleTime("2026-05-29T10:30:00-05:00"),
+				UpdatedAt:    &updatedAt,
+				Product:      "narrative",
+				Periods: []weatherdata.ForecastPeriod{
+					{
+						Name:                              "Today",
+						StartTime:                         mustParseModuleTime("2026-05-29T06:00:00-05:00"),
+						EndTime:                           mustParseModuleTime("2026-05-29T18:00:00-05:00"),
+						IsDay:                             &isDay,
+						TextDescription:                   "Morning storms, then partly sunny.",
+						TemperatureF:                      floatPtr(narrativeTempF),
+						WindSpeedMph:                      &narrativeWind,
+						WindDirectionDegrees:              &narrativeWindDirection,
+						ProbabilityOfPrecipitationPercent: &narrativePop,
+					},
+				},
+			},
+			Hourly: &weatherdata.ForecastRun{
+				LocationID:   "test-grid",
+				LocationName: "Testville",
+				IssuedAt:     mustParseModuleTime("2026-05-29T10:30:00-05:00"),
+				UpdatedAt:    &updatedAt,
+				Product:      "hourly",
+				Periods: []weatherdata.ForecastPeriod{
+					{
+						StartTime:                         mustParseModuleTime("2026-05-29T08:00:00-05:00"),
+						EndTime:                           mustParseModuleTime("2026-05-29T09:00:00-05:00"),
+						TextDescription:                   "Showers likely.",
+						TemperatureF:                      &hourlyTempF,
+						WindSpeedMph:                      &hourlyWindMph,
+						WindDirectionDegrees:              &windDirection,
+						ProbabilityOfPrecipitationPercent: &hourlyPop,
+						RelativeHumidityPercent:           &hourlyHumidity,
+					},
+					{
+						StartTime:       mustParseModuleTime("2026-05-30T08:00:00-05:00"),
+						EndTime:         mustParseModuleTime("2026-05-30T09:00:00-05:00"),
+						TextDescription: "Tomorrow showers.",
+					},
+				},
+			},
+			Alerts: &weatherdata.AlertRun{Alerts: []json.RawMessage{
+				json.RawMessage(`{"event":"Flood Watch","headline":"Flooding possible","severity":"Moderate"}`),
+			}},
+			Discussion: &weatherdata.Discussion{
+				Product:     "discussion",
+				KeyMessages: []string{"Scattered showers are possible."},
+				ShortTerm:   &weatherdata.DiscussionSection{Text: "Showers increase this afternoon."},
+				LongTerm:    &weatherdata.DiscussionSection{Text: "Periodic rain chances continue."},
+			},
+			WeatherStory: &weatherdata.WeatherStory{
+				OfficeID:    "LSX",
+				StartTime:   mustParseModuleTime("2026-05-29T06:00:00-05:00"),
+				EndTime:     mustParseModuleTime("2026-05-29T18:00:00-05:00"),
+				UpdatedAt:   &updatedAt,
+				Title:       "Rain Chances",
+				Description: "Scattered showers are possible.",
+				AltText:     "Weather story graphic with rain chances.",
+				Priority:    true,
+				Order:       1,
+				DownloadURL: "https://example.invalid/story.png",
+			},
+			SourceProvenance: []weatherdata.Source{{Name: "alerts", FetchedAt: generatedAt}},
+			SourceWarnings: []weatherdata.SourceWarning{{
+				Source:             "daily",
+				Code:               "missing_source",
+				Severity:           "warning",
+				Message:            "daily source is missing",
+				Endpoint:           "/forecast/daily",
+				CompletenessImpact: "source omitted",
+			}},
+		},
+		Derived: facts.DerivedFacts{
+			ValidPeriodHourlyPeriods: []weatherdata.ForecastPeriod{
+				{
+					StartTime:                         mustParseModuleTime("2026-05-29T08:00:00-05:00"),
+					EndTime:                           mustParseModuleTime("2026-05-29T09:00:00-05:00"),
+					TextDescription:                   "Showers likely.",
+					TemperatureF:                      &hourlyTempF,
+					WindSpeedMph:                      &hourlyWindMph,
+					WindDirectionDegrees:              &windDirection,
+					ProbabilityOfPrecipitationPercent: &hourlyPop,
+					RelativeHumidityPercent:           &hourlyHumidity,
+				},
+			},
+			ValidPeriodNarrativePeriods: []weatherdata.ForecastPeriod{
+				{
+					Name:                              "Today",
+					StartTime:                         mustParseModuleTime("2026-05-29T06:00:00-05:00"),
+					EndTime:                           mustParseModuleTime("2026-05-29T18:00:00-05:00"),
+					IsDay:                             &isDay,
+					TextDescription:                   "Morning storms, then partly sunny.",
+					TemperatureF:                      floatPtr(narrativeTempF),
+					WindSpeedMph:                      &narrativeWind,
+					WindDirectionDegrees:              &narrativeWindDirection,
+					ProbabilityOfPrecipitationPercent: &narrativePop,
+				},
+			},
+			AlertOverlaps: []forecast.AlertOverlap{{
+				Event:    "Flood Watch",
+				Headline: "Flooding possible",
+				Severity: "Moderate",
+			}},
+		},
+		Units:    "us",
+		Timezone: "America/Chicago",
+		Location: &LocationContext{
+			ID:       "home",
+			Name:     "Brentwood",
+			Region:   "St. Louis Metro",
+			Timezone: "America/Chicago",
+		},
+	}
+}
+
+func moduleValue[T any](t *testing.T, output *module.Output) T {
+	t.Helper()
+	var value T
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("marshal module value: %v", err)
+	}
+	if err := json.Unmarshal(data, &value); err != nil {
+		t.Fatalf("decode module value: %v", err)
+	}
+	return value
+}
+
+func mustParseModuleTime(value string) time.Time {
+	parsed, err := time.Parse(time.RFC3339, value)
+	if err != nil {
+		panic(err)
+	}
+	return parsed
+}

internal/briefing/current_conditions_module.go

@@ -0,0 +1,58 @@
+package briefing
+
+import "gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+
+type CurrentConditionsModule struct {
+	ConditionText           string   `json:"condition_text,omitempty"`
+	IsDay                   *bool    `json:"is_day,omitempty"`
+	TemperatureC            *float64 `json:"temperature_c,omitempty"`
+	TemperatureF            *float64 `json:"temperature_f,omitempty"`
+	ApparentTemperatureC    *float64 `json:"apparent_temperature_c,omitempty"`
+	ApparentTemperatureF    *float64 `json:"apparent_temperature_f,omitempty"`
+	DewpointC               *float64 `json:"dewpoint_c,omitempty"`
+	DewpointF               *float64 `json:"dewpoint_f,omitempty"`
+	RelativeHumidityPercent *float64 `json:"relative_humidity_percent,omitempty"`
+	WindSpeedKmh            *float64 `json:"wind_speed_kmh,omitempty"`
+	WindSpeedMph            *float64 `json:"wind_speed_mph,omitempty"`
+	WindDirection           string   `json:"wind_direction,omitempty"`
+}
+
+func buildCurrentConditionsModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	current := ctx.Collected.Current
+	if current == nil {
+		return nil, nil
+	}
+	value := CurrentConditionsModule{
+		ConditionText:           current.ConditionText,
+		IsDay:                   copyBool(current.IsDay),
+		TemperatureC:            copyFloat(current.TemperatureC),
+		TemperatureF:            copyFloat(current.TemperatureF),
+		ApparentTemperatureC:    copyFloat(current.ApparentTemperatureC),
+		ApparentTemperatureF:    copyFloat(current.ApparentTemperatureF),
+		DewpointC:               copyFloat(current.DewpointC),
+		DewpointF:               copyFloat(current.DewpointF),
+		RelativeHumidityPercent: copyFloat(current.RelativeHumidityPercent),
+		WindSpeedKmh:            copyFloat(current.WindSpeedKmh),
+		WindSpeedMph:            copyFloat(current.WindSpeedMph),
+		WindDirection:           windDirectionLabel(current.WindDirectionDegrees),
+	}
+	if value.isEmpty() {
+		return nil, nil
+	}
+	return &module.Output{ID: module.CurrentConditions, StanzaName: "current_conditions", Value: value}, nil
+}
+
+func (v CurrentConditionsModule) isEmpty() bool {
+	return v.ConditionText == "" &&
+		v.IsDay == nil &&
+		v.TemperatureC == nil &&
+		v.TemperatureF == nil &&
+		v.ApparentTemperatureC == nil &&
+		v.ApparentTemperatureF == nil &&
+		v.DewpointC == nil &&
+		v.DewpointF == nil &&
+		v.RelativeHumidityPercent == nil &&
+		v.WindSpeedKmh == nil &&
+		v.WindSpeedMph == nil &&
+		v.WindDirection == ""
+}

internal/briefing/derived_daily_summary_module.go

@@ -0,0 +1,153 @@
+package briefing
+
+import (
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type DerivedDailySummaryModule struct {
+	Date                          string   `json:"date,omitempty"`
+	HighTempF                     *int     `json:"high_temp_f,omitempty"`
+	LowTempF                      *int     `json:"low_temp_f,omitempty"`
+	DailyPrecipitationProbability *int     `json:"daily_precipitation_probability,omitempty"`
+	MostLikelyPrecipitationHour   string   `json:"most_likely_precipitation_hour,omitempty"`
+	ThunderMentioned              bool     `json:"thunder_mentioned"`
+	MaxWindGustMph                *int     `json:"max_wind_gust_mph,omitempty"`
+	HeatIndexMaxF                 *int     `json:"heat_index_max_f,omitempty"`
+	DominantConditions            []string `json:"dominant_conditions,omitempty"`
+	Hazards                       []string `json:"hazards,omitempty"`
+}
+
+func buildDerivedDailySummaryModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	summary := ctx.Derived.FirstDailySummary()
+	if summary == nil {
+		return nil, fmt.Errorf("daily summary facts are required")
+	}
+	value, err := derivedDailySummaryValue(*summary, ctx.Derived.PrecipTiming, ctx.Timezone)
+	if err != nil {
+		return nil, err
+	}
+	return &module.Output{ID: module.DerivedDailySummary, StanzaName: "derived_daily_summary", Value: value}, nil
+}
+
+func derivedDailySummaryValue(summary forecast.DailySummary, timing forecast.PrecipTiming, timezone string) (DerivedDailySummaryModule, error) {
+	value := DerivedDailySummaryModule{
+		Date:             friendlyDateLabel(summary.Date, timezone),
+		ThunderMentioned: timing.ThunderMentioned,
+	}
+	conditions := map[string]struct{}{}
+	hazards := map[string]struct{}{}
+	var temperature forecast.Range
+	var apparent forecast.Range
+	var maxPop *forecast.TimedValue
+	var maxGust *forecast.TimedValue
+	for _, daypart := range summary.Dayparts {
+		addRange(&temperature, daypart.Temperature)
+		addRange(&apparent, daypart.ApparentTemperature)
+		maxTimedValue(&maxPop, daypart.MaxPrecipitationProbability)
+		maxTimedValue(&maxGust, daypart.PeakWindGust)
+		if daypart.DominantCondition != "" {
+			conditions[daypart.DominantCondition] = struct{}{}
+		}
+		for _, hazard := range hazardsForIndicators(daypart.Indicators) {
+			hazards[hazard] = struct{}{}
+		}
+	}
+	for _, alert := range summary.AlertOverlaps {
+		if alert.Event != "" {
+			hazards[alert.Event] = struct{}{}
+		}
+	}
+	narrativeTemperature := narrativeTemperatureRange(summary.NarrativePeriods)
+	if narrativeTemperature.Max != nil {
+		value.HighTempF = roundedInt(narrativeTemperature.Max)
+	} else {
+		value.HighTempF = roundedInt(temperature.Max)
+	}
+	if narrativeTemperature.Min != nil {
+		value.LowTempF = roundedInt(narrativeTemperature.Min)
+	} else {
+		value.LowTempF = roundedInt(temperature.Min)
+	}
+	value.HeatIndexMaxF = roundedInt(apparent.Max)
+	narrativePrecipitation := narrativeMaxPrecipitation(summary.NarrativePeriods)
+	if narrativePrecipitation != nil {
+		value.DailyPrecipitationProbability = roundedInt(&narrativePrecipitation.Value)
+	} else if maxPop != nil {
+		value.DailyPrecipitationProbability = roundedInt(&maxPop.Value)
+	}
+	if maxPop != nil {
+		value.MostLikelyPrecipitationHour = mostLikelyPrecipitationHour(maxPop, timezone)
+	}
+	if maxGust != nil {
+		value.MaxWindGustMph = roundedInt(&maxGust.Value)
+	}
+	value.DominantConditions = sortedSet(conditions)
+	value.Hazards = sortedSet(hazards)
+	return value, nil
+}
+
+func narrativeTemperatureRange(periods []weatherdata.ForecastPeriod) forecast.Range {
+	var out forecast.Range
+	for _, period := range periods {
+		addNarrativeHigh(&out, period.TemperatureFMax)
+		addNarrativeLow(&out, period.TemperatureFMin)
+		if period.TemperatureF != nil && period.IsDay != nil {
+			if *period.IsDay {
+				addNarrativeHigh(&out, period.TemperatureF)
+			} else {
+				addNarrativeLow(&out, period.TemperatureF)
+			}
+		}
+	}
+	return out
+}
+
+func addNarrativeHigh(target *forecast.Range, value *float64) {
+	if value == nil {
+		return
+	}
+	if target.Max == nil || *value > *target.Max {
+		copied := *value
+		target.Max = &copied
+	}
+}
+
+func addNarrativeLow(target *forecast.Range, value *float64) {
+	if value == nil {
+		return
+	}
+	if target.Min == nil || *value < *target.Min {
+		copied := *value
+		target.Min = &copied
+	}
+}
+
+func narrativeMaxPrecipitation(periods []weatherdata.ForecastPeriod) *forecast.TimedValue {
+	var maxPop *forecast.TimedValue
+	for _, period := range periods {
+		if period.ProbabilityOfPrecipitationPercent == nil {
+			continue
+		}
+		value := forecast.TimedValue{
+			Value: *period.ProbabilityOfPrecipitationPercent,
+			Time:  period.StartTime,
+		}
+		maxTimedValue(&maxPop, &value)
+	}
+	return maxPop
+}
+
+func mostLikelyPrecipitationHour(maxPop *forecast.TimedValue, timezone string) string {
+	if maxPop == nil || maxPop.Value <= 0 {
+		return ""
+	}
+	percent := roundedInt(&maxPop.Value)
+	if percent == nil {
+		return ""
+	}
+	return fmt.Sprintf("%d%% at %s", *percent, clockLabel(maxPop.Time, timezone))
+}

internal/briefing/derived_daypart_summaries_module.go

@@ -0,0 +1,108 @@
+package briefing
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+type DerivedDaypartSummaryModule struct {
+	Date               string   `json:"date,omitempty"`
+	Period             string   `json:"period,omitempty"`
+	TempRangeF         string   `json:"temp_range_f,omitempty"`
+	ApparentTempRangeF string   `json:"apparent_temp_range_f,omitempty"`
+	MaxPopPercent      *int     `json:"max_pop_percent,omitempty"`
+	MaxPopTime         string   `json:"max_pop_time,omitempty"`
+	MaxWindGustMph     *int     `json:"max_wind_gust_mph,omitempty"`
+	MaxWindGustTime    string   `json:"max_wind_gust_time,omitempty"`
+	DominantCondition  string   `json:"dominant_condition,omitempty"`
+	NotableConditions  []string `json:"notable_conditions,omitempty"`
+	Snow               bool     `json:"snow,omitempty"`
+	Ice                bool     `json:"ice,omitempty"`
+	Fog                bool     `json:"fog,omitempty"`
+	Heat               bool     `json:"heat,omitempty"`
+	Cold               bool     `json:"cold,omitempty"`
+	Wind               bool     `json:"wind,omitempty"`
+	RelevantAlertCount int      `json:"relevant_alert_count,omitempty"`
+}
+
+func buildDerivedDaypartSummariesModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	if len(ctx.Derived.DaypartSummaries) == 0 {
+		return nil, fmt.Errorf("daypart summary facts are required")
+	}
+	value := map[string]DerivedDaypartSummaryModule{}
+	prefixDates := multipleSummaryDates(ctx.Derived.DailySummaries)
+	for _, daypart := range ctx.Derived.DaypartSummaries {
+		key := daypartKey(daypart, prefixDates)
+		value[key] = derivedDaypartSummaryValue(daypart, ctx.Timezone)
+	}
+	return &module.Output{ID: module.DerivedDaypartSummaries, StanzaName: "derived_daypart_summaries", Value: value}, nil
+}
+
+func derivedDaypartSummaryValue(daypart forecast.DaypartSummary, timezone string) DerivedDaypartSummaryModule {
+	value := DerivedDaypartSummaryModule{
+		Date:               localDateLabel(daypart.Period.Start, timezone),
+		Period:             friendlyPeriodLabel(daypart.Period, timezone),
+		TempRangeF:         rangeLabel(daypart.Temperature),
+		ApparentTempRangeF: daypartApparentRangeLabel(daypart.ApparentTemperature),
+		DominantCondition:  daypart.DominantCondition,
+		NotableConditions:  append([]string(nil), daypart.NotableConditions...),
+		Snow:               daypart.Indicators.Snow,
+		Ice:                daypart.Indicators.Ice,
+		Fog:                daypart.Indicators.Fog,
+		Heat:               daypart.Indicators.Heat,
+		Cold:               daypart.Indicators.Cold,
+		Wind:               daypart.Indicators.Wind,
+		RelevantAlertCount: len(daypart.AlertOverlaps),
+	}
+	if daypart.MaxPrecipitationProbability != nil {
+		value.MaxPopPercent = roundedInt(&daypart.MaxPrecipitationProbability.Value)
+		value.MaxPopTime = clockLabel(daypart.MaxPrecipitationProbability.Time, timezone)
+	}
+	if daypart.PeakWindGust != nil {
+		value.MaxWindGustMph = roundedInt(&daypart.PeakWindGust.Value)
+		value.MaxWindGustTime = clockLabel(daypart.PeakWindGust.Time, timezone)
+	}
+	return value
+}
+
+func multipleSummaryDates(summaries []forecast.DailySummary) bool {
+	seen := map[string]struct{}{}
+	for _, summary := range summaries {
+		seen[summary.Date] = struct{}{}
+	}
+	return len(seen) > 1
+}
+
+func daypartKey(daypart forecast.DaypartSummary, prefixDate bool) string {
+	key := normalizedKey(daypart.Name)
+	if key == "" {
+		key = "unnamed"
+	}
+	if !prefixDate {
+		return key
+	}
+	return daypart.Period.Start.Format(timeutil.DateLayout) + "_" + key
+}
+
+func normalizedKey(value string) string {
+	lower := strings.ToLower(strings.TrimSpace(value))
+	var out strings.Builder
+	lastUnderscore := false
+	for _, r := range lower {
+		if unicode.IsLetter(r) || unicode.IsDigit(r) {
+			out.WriteRune(r)
+			lastUnderscore = false
+			continue
+		}
+		if !lastUnderscore {
+			out.WriteByte('_')
+			lastUnderscore = true
+		}
+	}
+	return strings.Trim(out.String(), "_")
+}

internal/briefing/derived_modules_test.go

@@ -0,0 +1,342 @@
+package briefing
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+func TestDerivedDailySummaryModulePackagesOrdinaryForecast(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyToday)
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.DerivedDailySummary})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[DerivedDailySummaryModule](t, output)
+
+	if value.Date != "Friday, May 29, 2026" {
+		t.Fatalf("Date = %q, want friendly local date", value.Date)
+	}
+	if value.HighTempF == nil || *value.HighTempF != 88 || value.LowTempF == nil || *value.LowTempF != 64 {
+		t.Fatalf("daily temperatures = %#v/%#v, want narrative 88/64", value.HighTempF, value.LowTempF)
+	}
+	if value.DailyPrecipitationProbability == nil || *value.DailyPrecipitationProbability != 55 {
+		t.Fatalf("DailyPrecipitationProbability = %#v, want narrative 55", value.DailyPrecipitationProbability)
+	}
+	if value.MostLikelyPrecipitationHour != "80% at 12 PM" || !value.ThunderMentioned {
+		t.Fatalf("precip timing = %#v, want most likely hour and thunder", value)
+	}
+	if !containsString(value.DominantConditions, "Thunderstorms with gusty wind") || containsString(value.DominantConditions, "Morning storms, then partly sunny.") {
+		t.Fatalf("DominantConditions = %#v, want daypart conditions rather than narrative conditions", value.DominantConditions)
+	}
+	if value.MaxWindGustMph == nil || *value.MaxWindGustMph != 42 {
+		t.Fatalf("MaxWindGustMph = %#v, want 42", value.MaxWindGustMph)
+	}
+	if value.HeatIndexMaxF == nil || *value.HeatIndexMaxF != 101 {
+		t.Fatalf("HeatIndexMaxF = %#v, want 101", value.HeatIndexMaxF)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("marshal daily summary: %v", err)
+	}
+	jsonText := string(data)
+	for _, field := range []string{"high_temp_f", "low_temp_f", "daily_precipitation_probability", "most_likely_precipitation_hour", "heat_index_max_f"} {
+		if !strings.Contains(jsonText, field) {
+			t.Fatalf("daily json = %s, want field %s", jsonText, field)
+		}
+	}
+	for _, removed := range []string{"max_pop_percent", "max_pop_window", "first_precip_hour", "last_precip_hour"} {
+		if strings.Contains(jsonText, removed) {
+			t.Fatalf("daily json = %s, want removed field %s omitted", jsonText, removed)
+		}
+	}
+	if strings.Contains(jsonText, "qpf") {
+		t.Fatalf("daily json = %s, want no QPF fields without upstream QPF facts", jsonText)
+	}
+}
+
+func TestDerivedDailySummaryModuleFallsBackWithoutNarrativeFacts(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyToday)
+	ctx.Derived.DailySummaries[0].NarrativePeriods = nil
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.DerivedDailySummary})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[DerivedDailySummaryModule](t, output)
+
+	if value.HighTempF == nil || *value.HighTempF != 96 || value.LowTempF == nil || *value.LowTempF != 31 {
+		t.Fatalf("daily temperatures = %#v/%#v, want fallback 96/31", value.HighTempF, value.LowTempF)
+	}
+	if value.DailyPrecipitationProbability == nil || *value.DailyPrecipitationProbability != 80 {
+		t.Fatalf("DailyPrecipitationProbability = %#v, want hourly fallback 80", value.DailyPrecipitationProbability)
+	}
+	if len(value.DominantConditions) == 0 || !containsString(value.DominantConditions, "Thunderstorms with gusty wind") {
+		t.Fatalf("DominantConditions = %#v, want fallback daypart conditions", value.DominantConditions)
+	}
+}
+
+func TestPrecipTimingModuleHandlesRainyAndDryForecasts(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyToday)
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.PrecipTiming})
+	if err != nil {
+		t.Fatalf("BuildModule(rainy) error = %v", err)
+	}
+	rainy := moduleValue[PrecipTimingModule](t, output)
+	if rainy.MaxPopPercent == nil || *rainy.MaxPopPercent != 80 || rainy.MaxPopTime != "12 PM" || rainy.ProbabilityThreshold != forecast.DefaultPrecipWindowProbabilityThreshold || !rainy.ThunderMentioned {
+		t.Fatalf("rainy precip timing = %#v, want peak, threshold, and thunder", rainy)
+	}
+	if len(rainy.PrecipitationWindows) != 2 {
+		t.Fatalf("rainy precipitation windows = %#v, want two windows", rainy.PrecipitationWindows)
+	}
+	if rainy.PrecipitationWindows[0].Start != "8 AM" || rainy.PrecipitationWindows[0].End != "9 AM" || rainy.PrecipitationWindows[0].MaxPopPercent == nil || *rainy.PrecipitationWindows[0].MaxPopPercent != 60 {
+		t.Fatalf("first precipitation window = %#v, want 8-9 AM at 60%%", rainy.PrecipitationWindows[0])
+	}
+	if rainy.PrecipitationWindows[1].Start != "12 PM" || rainy.PrecipitationWindows[1].End != "2 PM" || rainy.PrecipitationWindows[1].MaxPopPercent == nil || *rainy.PrecipitationWindows[1].MaxPopPercent != 80 {
+		t.Fatalf("second precipitation window = %#v, want noon-2 PM at 80%%", rainy.PrecipitationWindows[1])
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("marshal precip timing: %v", err)
+	}
+	if !strings.Contains(string(data), "precipitation_windows") || !strings.Contains(string(data), "probability_threshold") {
+		t.Fatalf("precip timing json = %s, want threshold and windows", string(data))
+	}
+	if strings.Contains(string(data), "first_precip_hour") || strings.Contains(string(data), "last_precip_hour") {
+		t.Fatalf("precip timing json = %s, want no ambiguous first/last fields", string(data))
+	}
+
+	ctx.Derived.PrecipTiming = forecast.BuildPrecipTiming([]weatherdata.ForecastPeriod{derivedHour("2026-05-29T10:00:00-05:00", "Sunny", 0, 70, nil, 5)})
+	output, err = registry.BuildModule(ctx, module.ConfigItem{ID: module.PrecipTiming})
+	if err != nil {
+		t.Fatalf("BuildModule(dry) error = %v", err)
+	}
+	dry := moduleValue[PrecipTimingModule](t, output)
+	if len(dry.PrecipitationWindows) != 0 || dry.ThunderMentioned {
+		t.Fatalf("dry precip timing = %#v, want no precip windows and no thunder", dry)
+	}
+	if dry.MaxPopPercent == nil || *dry.MaxPopPercent != 0 {
+		t.Fatalf("dry MaxPopPercent = %#v, want checked zero", dry.MaxPopPercent)
+	}
+}
+
+func TestDerivedDaypartSummariesExposeConfiguredKeysAndHazards(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyToday)
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.DerivedDaypartSummaries})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[map[string]DerivedDaypartSummaryModule](t, output)
+
+	morning, ok := value["morning"]
+	if !ok {
+		t.Fatalf("daypart keys = %#v, want configured morning key", value)
+	}
+	if morning.TempRangeF != "58" || morning.MaxPopPercent == nil || *morning.MaxPopPercent != 60 {
+		t.Fatalf("morning = %#v, want temp range and precip peak", morning)
+	}
+	if morning.Date != "2026-05-29" || morning.Period != "2026-05-29 at 6:00 AM to 2026-05-29 at 12:00 PM" {
+		t.Fatalf("morning period = %q/%q, want friendly local date and period labels", morning.Date, morning.Period)
+	}
+	afternoon := value["afternoon"]
+	if !afternoon.Heat || !afternoon.Wind || afternoon.MaxWindGustMph == nil || *afternoon.MaxWindGustMph != 42 {
+		t.Fatalf("afternoon = %#v, want heat and wind hazard values", afternoon)
+	}
+	overnight := value["overnight"]
+	if !overnight.Cold {
+		t.Fatalf("overnight = %#v, want cold hazard", overnight)
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		t.Fatalf("marshal daypart summaries: %v", err)
+	}
+	jsonText := string(data)
+	for _, field := range []string{"date", "period", "temp_range_f", "max_pop_percent", "max_wind_gust_mph", "dominant_condition"} {
+		if !strings.Contains(jsonText, field) {
+			t.Fatalf("daypart json = %s, want field %s", jsonText, field)
+		}
+	}
+	if strings.Contains(jsonText, `"period":{"start"`) || strings.Contains(jsonText, `T06:00:00`) {
+		t.Fatalf("daypart json = %s, want friendly period label instead of raw timestamps", jsonText)
+	}
+}
+
+func TestOutdoorWindowsAndTomorrowPlanningModulesPreserveDailyContent(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyTomorrow)
+
+	outdoorOutput, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.OutdoorWindows})
+	if err != nil {
+		t.Fatalf("BuildModule(outdoor windows) error = %v", err)
+	}
+	outdoor := moduleValue[OutdoorWindowsModule](t, outdoorOutput)
+	if outdoor.Best == nil || outdoor.Worst == nil {
+		t.Fatalf("outdoor windows = %#v, want best and worst", outdoor)
+	}
+	if outdoor.Best.Daypart != "overnight" || outdoor.Worst.Daypart != "afternoon" {
+		t.Fatalf("outdoor windows = %#v, want quiet overnight and stormy afternoon", outdoor)
+	}
+
+	planningOutput, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.TomorrowPlanning})
+	if err != nil {
+		t.Fatalf("BuildModule(tomorrow planning) error = %v", err)
+	}
+	planning := moduleValue[TomorrowPlanningModule](t, planningOutput)
+	if len(planning.MorningReadiness) == 0 || len(planning.CommuteSchoolWorkdayConcerns) == 0 || len(planning.OvernightChangeWatch) == 0 {
+		t.Fatalf("tomorrow planning = %#v, want daily planning notes", planning)
+	}
+	data, err := json.Marshal(planningOutput.Value)
+	if err != nil {
+		t.Fatalf("marshal tomorrow planning: %v", err)
+	}
+	if !strings.Contains(string(data), "morning_readiness") || strings.Contains(string(data), "morningReadiness") {
+		t.Fatalf("tomorrow planning json = %s, want snake_case fields", string(data))
+	}
+}
+
+func TestDerivedModulesHandleMissingData(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.DailyToday)
+	ctx.Derived.DailySummaries = nil
+	ctx.Derived.DaypartSummaries = nil
+
+	if _, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.DerivedDailySummary}); err == nil {
+		t.Fatal("BuildModule(derived daily summary) error = nil, want required facts error")
+	}
+	if _, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.DerivedDaypartSummaries}); err == nil {
+		t.Fatal("BuildModule(daypart summaries) error = nil, want required facts error")
+	}
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.OutdoorWindows})
+	if err != nil {
+		t.Fatalf("BuildModule(outdoor windows) error = %v", err)
+	}
+	windows := moduleValue[OutdoorWindowsModule](t, output)
+	if windows.Best != nil || windows.Worst != nil {
+		t.Fatalf("outdoor windows = %#v, want empty output with missing dayparts", windows)
+	}
+}
+
+func derivedModuleContext(id report.ID) ModuleContext {
+	generatedAt := mustParseModuleTime("2026-05-29T08:00:00-05:00")
+	definition := report.DefaultRegistry().MustLookup(id)
+	summary := forecast.DailySummary{
+		Date: "2026-05-29",
+		Period: timeutil.Period{
+			Start: mustParseModuleTime("2026-05-29T00:00:00-05:00"),
+			End:   mustParseModuleTime("2026-05-30T00:00:00-05:00"),
+		},
+		Dayparts: []forecast.DaypartSummary{
+			derivedDaypart("overnight", "2026-05-29T00:00:00-05:00", "2026-05-29T06:00:00-05:00", "Clear and cold", 31, nil, 0, 5),
+			derivedDaypart("morning", "2026-05-29T06:00:00-05:00", "2026-05-29T12:00:00-05:00", "Showers", 58, nil, 60, 15),
+			derivedDaypart("afternoon", "2026-05-29T12:00:00-05:00", "2026-05-29T18:00:00-05:00", "Thunderstorms with gusty wind", 96, floatPtr(101), 80, 42),
+		},
+	}
+	hours := []weatherdata.ForecastPeriod{
+		derivedHour("2026-05-29T00:00:00-05:00", "Clear and cold", 0, 31, nil, 5),
+		derivedHour("2026-05-29T08:00:00-05:00", "Showers", 60, 58, nil, 15),
+		derivedHour("2026-05-29T09:00:00-05:00", "Dry break", 20, 62, nil, 10),
+		derivedHour("2026-05-29T12:00:00-05:00", "Thunderstorms with gusty wind", 80, 96, floatPtr(101), 42),
+		derivedHour("2026-05-29T13:00:00-05:00", "Heavy rain", 70, 82, nil, 30),
+		derivedHour("2026-05-29T14:00:00-05:00", "Drying out", 20, 78, nil, 12),
+	}
+	narrative := []weatherdata.ForecastPeriod{
+		{
+			Name:                              "Today",
+			StartTime:                         mustParseModuleTime("2026-05-29T06:00:00-05:00"),
+			EndTime:                           mustParseModuleTime("2026-05-29T18:00:00-05:00"),
+			IsDay:                             boolPtr(true),
+			TextDescription:                   "Morning storms, then partly sunny.",
+			TemperatureFMax:                   floatPtr(88),
+			ProbabilityOfPrecipitationPercent: floatPtr(55),
+		},
+		{
+			Name:                              "Tonight",
+			StartTime:                         mustParseModuleTime("2026-05-29T18:00:00-05:00"),
+			EndTime:                           mustParseModuleTime("2026-05-30T00:00:00-05:00"),
+			IsDay:                             boolPtr(false),
+			TextDescription:                   "Clouds linger tonight.",
+			TemperatureFMin:                   floatPtr(64),
+			ProbabilityOfPrecipitationPercent: floatPtr(30),
+		},
+	}
+	summary.Dayparts[2].AlertOverlaps = []forecast.AlertOverlap{{Event: "Severe Thunderstorm Watch"}}
+	summary.NarrativePeriods = append([]weatherdata.ForecastPeriod(nil), narrative...)
+	return ModuleContext{
+		Resolved: report.Resolved{
+			Definition:  definition,
+			GeneratedAt: generatedAt,
+			Timezone:    "America/Chicago",
+			ValidPeriod: summary.Period,
+		},
+		Collected: facts.CollectedFacts{
+			Narrative: &weatherdata.ForecastRun{
+				IssuedAt: mustParseModuleTime("2026-05-29T10:30:00-05:00"),
+				Product:  "narrative",
+				Periods:  append([]weatherdata.ForecastPeriod(nil), narrative...),
+			},
+		},
+		Derived: facts.DerivedFacts{
+			ValidPeriodHourlyPeriods:    hours,
+			ValidPeriodNarrativePeriods: narrative,
+			DailySummaries:              []forecast.DailySummary{summary},
+			DaypartSummaries:            append([]forecast.DaypartSummary(nil), summary.Dayparts...),
+			PrecipTiming:                forecast.BuildPrecipTiming(hours),
+		},
+		Units:    "us",
+		Timezone: "America/Chicago",
+	}
+}
+
+func derivedDaypart(name string, start string, end string, text string, temperature float64, apparent *float64, precip float64, gust float64) forecast.DaypartSummary {
+	hour := derivedHour(start, text, precip, temperature, apparent, gust)
+	return forecast.SummarizeDaypart(name, timeutil.Period{
+		Start: mustParseModuleTime(start),
+		End:   mustParseModuleTime(end),
+	}, []weatherdata.ForecastPeriod{hour})
+}
+
+func derivedHour(start string, text string, precip float64, temperature float64, apparent *float64, gust float64) weatherdata.ForecastPeriod {
+	startTime := mustParseModuleTime(start)
+	endTime := startTime.Add(time.Hour)
+	return weatherdata.ForecastPeriod{
+		StartTime:                         startTime,
+		EndTime:                           endTime,
+		TextDescription:                   text,
+		TemperatureF:                      floatPtr(temperature),
+		ApparentTemperatureF:              apparent,
+		ProbabilityOfPrecipitationPercent: floatPtr(precip),
+		WindGustMph:                       floatPtr(gust),
+	}
+}
+
+func floatPtr(value float64) *float64 {
+	return &value
+}
+
+func boolPtr(value bool) *bool {
+	return &value
+}
+
+func containsString(values []string, want string) bool {
+	for _, value := range values {
+		if value == want {
+			return true
+		}
+	}
+	return false
+}

internal/briefing/hourly_forecast_module.go

@@ -0,0 +1,123 @@
+package briefing
+
+import (
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type HourlyForecastModule struct {
+	Product          string                 `json:"product,omitempty"`
+	IssuedAt         time.Time              `json:"issued_at,omitempty"`
+	UpdatedAt        *time.Time             `json:"updated_at,omitempty"`
+	SourceLocation   string                 `json:"source_location,omitempty"`
+	SourceLocationID string                 `json:"source_location_id,omitempty"`
+	Periods          []HourlyForecastPeriod `json:"periods,omitempty"`
+}
+
+type HourlyForecastPeriod struct {
+	StartTime                         string   `json:"start_time,omitempty"`
+	EndTime                           string   `json:"end_time,omitempty"`
+	Name                              string   `json:"name,omitempty"`
+	IsDay                             *bool    `json:"is_day,omitempty"`
+	ConditionCode                     *int     `json:"condition_code,omitempty"`
+	TextDescription                   string   `json:"text_description,omitempty"`
+	TemperatureC                      *float64 `json:"temperature_c,omitempty"`
+	TemperatureF                      *float64 `json:"temperature_f,omitempty"`
+	TemperatureCMin                   *float64 `json:"temperature_c_min,omitempty"`
+	TemperatureFMin                   *float64 `json:"temperature_f_min,omitempty"`
+	TemperatureCMax                   *float64 `json:"temperature_c_max,omitempty"`
+	TemperatureFMax                   *float64 `json:"temperature_f_max,omitempty"`
+	DewpointC                         *float64 `json:"dewpoint_c,omitempty"`
+	DewpointF                         *float64 `json:"dewpoint_f,omitempty"`
+	WindSpeedKmh                      *float64 `json:"wind_speed_kmh,omitempty"`
+	WindSpeedMph                      *float64 `json:"wind_speed_mph,omitempty"`
+	WindGustKmh                       *float64 `json:"wind_gust_kmh,omitempty"`
+	WindGustMph                       *float64 `json:"wind_gust_mph,omitempty"`
+	WindDirection                     string   `json:"wind_direction,omitempty"`
+	BarometricPressurePa              *float64 `json:"barometric_pressure_pa,omitempty"`
+	BarometricPressureInHg            *float64 `json:"barometric_pressure_in_hg,omitempty"`
+	VisibilityMeters                  *float64 `json:"visibility_meters,omitempty"`
+	VisibilityMiles                   *float64 `json:"visibility_miles,omitempty"`
+	ApparentTemperatureC              *float64 `json:"apparent_temperature_c,omitempty"`
+	ApparentTemperatureF              *float64 `json:"apparent_temperature_f,omitempty"`
+	CloudCoverPercent                 *float64 `json:"cloud_cover_percent,omitempty"`
+	ProbabilityOfPrecipitationPercent *float64 `json:"probability_of_precipitation_percent,omitempty"`
+	PrecipitationAmountMm             *float64 `json:"precipitation_amount_mm,omitempty"`
+	PrecipitationAmountIn             *float64 `json:"precipitation_amount_in,omitempty"`
+	SnowfallDepthMM                   *float64 `json:"snowfall_depth_mm,omitempty"`
+	SnowfallDepthIn                   *float64 `json:"snowfall_depth_in,omitempty"`
+	UVIndex                           *float64 `json:"uv_index,omitempty"`
+	RelativeHumidityPercent           *float64 `json:"relative_humidity_percent,omitempty"`
+}
+
+func buildHourlyForecastModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	hourly := ctx.Collected.Hourly
+	if hourly == nil || len(ctx.Derived.ValidPeriodHourlyPeriods) == 0 {
+		return nil, nil
+	}
+	value := HourlyForecastModule{
+		Product:          hourly.Product,
+		IssuedAt:         hourly.IssuedAt,
+		UpdatedAt:        copyTime(hourly.UpdatedAt),
+		SourceLocation:   hourly.LocationName,
+		SourceLocationID: hourly.LocationID,
+		Periods:          hourlyForecastPeriods(ctx.Derived.ValidPeriodHourlyPeriods, ctx.Timezone),
+	}
+	if value.isEmpty() {
+		return nil, nil
+	}
+	return &module.Output{ID: module.HourlyForecast, StanzaName: "hourly_forecast", Value: value}, nil
+}
+
+func hourlyForecastPeriods(periods []weatherdata.ForecastPeriod, timezone string) []HourlyForecastPeriod {
+	out := make([]HourlyForecastPeriod, 0, len(periods))
+	for _, period := range periods {
+		out = append(out, HourlyForecastPeriod{
+			StartTime:                         friendlyDateTimeLabel(period.StartTime, timezone),
+			EndTime:                           friendlyDateTimeLabel(period.EndTime, timezone),
+			Name:                              period.Name,
+			IsDay:                             copyBool(period.IsDay),
+			ConditionCode:                     copyInt(period.ConditionCode),
+			TextDescription:                   period.TextDescription,
+			TemperatureC:                      copyFloat(period.TemperatureC),
+			TemperatureF:                      copyFloat(period.TemperatureF),
+			TemperatureCMin:                   copyFloat(period.TemperatureCMin),
+			TemperatureFMin:                   copyFloat(period.TemperatureFMin),
+			TemperatureCMax:                   copyFloat(period.TemperatureCMax),
+			TemperatureFMax:                   copyFloat(period.TemperatureFMax),
+			DewpointC:                         copyFloat(period.DewpointC),
+			DewpointF:                         copyFloat(period.DewpointF),
+			WindSpeedKmh:                      copyFloat(period.WindSpeedKmh),
+			WindSpeedMph:                      copyFloat(period.WindSpeedMph),
+			WindGustKmh:                       copyFloat(period.WindGustKmh),
+			WindGustMph:                       copyFloat(period.WindGustMph),
+			WindDirection:                     windDirectionLabel(period.WindDirectionDegrees),
+			BarometricPressurePa:              copyFloat(period.BarometricPressurePa),
+			BarometricPressureInHg:            copyFloat(period.BarometricPressureInHg),
+			VisibilityMeters:                  copyFloat(period.VisibilityMeters),
+			VisibilityMiles:                   copyFloat(period.VisibilityMiles),
+			ApparentTemperatureC:              copyFloat(period.ApparentTemperatureC),
+			ApparentTemperatureF:              copyFloat(period.ApparentTemperatureF),
+			CloudCoverPercent:                 copyFloat(period.CloudCoverPercent),
+			ProbabilityOfPrecipitationPercent: copyFloat(period.ProbabilityOfPrecipitationPercent),
+			PrecipitationAmountMm:             copyFloat(period.PrecipitationAmountMm),
+			PrecipitationAmountIn:             copyFloat(period.PrecipitationAmountIn),
+			SnowfallDepthMM:                   copyFloat(period.SnowfallDepthMM),
+			SnowfallDepthIn:                   copyFloat(period.SnowfallDepthIn),
+			UVIndex:                           copyFloat(period.UVIndex),
+			RelativeHumidityPercent:           copyFloat(period.RelativeHumidityPercent),
+		})
+	}
+	return out
+}
+
+func (v HourlyForecastModule) isEmpty() bool {
+	return v.Product == "" &&
+		v.IssuedAt.IsZero() &&
+		v.UpdatedAt == nil &&
+		v.SourceLocation == "" &&
+		v.SourceLocationID == "" &&
+		len(v.Periods) == 0
+}

internal/briefing/metadata_module.go

@@ -0,0 +1,64 @@
+package briefing
+
+import (
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type MetadataModule struct {
+	RunID          string                 `json:"run_id"`
+	ReportID       report.ID              `json:"report_id"`
+	Variant        string                 `json:"variant,omitempty"`
+	PromptID       string                 `json:"prompt_id"`
+	GeneratedAt    time.Time              `json:"generated_at"`
+	Units          string                 `json:"units"`
+	Timezone       string                 `json:"timezone"`
+	ValidPeriod    timeutil.Period        `json:"valid_period"`
+	Location       *LocationContext       `json:"location,omitempty"`
+	SourceWarnings []SourceWarningSummary `json:"source_warnings,omitempty"`
+	Alerts         *AlertDigestModule     `json:"alerts,omitempty"`
+}
+
+type SourceWarningSummary struct {
+	Source             string `json:"source"`
+	Code               string `json:"code"`
+	Severity           string `json:"severity"`
+	Message            string `json:"message"`
+	CompletenessImpact string `json:"completeness_impact,omitempty"`
+}
+
+func buildMetadataModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	metadata := ctx.Resolved.Metadata()
+	value := MetadataModule{
+		RunID:          metadata.RunID,
+		ReportID:       metadata.ReportID,
+		Variant:        variantForReport(metadata.ReportID),
+		PromptID:       metadata.PromptID,
+		GeneratedAt:    metadata.GeneratedAt,
+		Units:          ctx.Units,
+		Timezone:       ctx.Timezone,
+		ValidPeriod:    metadata.ValidPeriod,
+		Location:       copyLocation(ctx.Location),
+		SourceWarnings: sourceWarningSummaries(ctx.Collected.SourceWarnings),
+		Alerts:         alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps),
+	}
+	return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: value}, nil
+}
+
+func sourceWarningSummaries(warnings []weatherdata.SourceWarning) []SourceWarningSummary {
+	out := make([]SourceWarningSummary, 0, len(warnings))
+	for _, warning := range warnings {
+		out = append(out, SourceWarningSummary{
+			Source:             warning.Source,
+			Code:               warning.Code,
+			Severity:           warning.Severity,
+			Message:            warning.Message,
+			CompletenessImpact: warning.CompletenessImpact,
+		})
+	}
+	return out
+}

internal/briefing/module_format_helpers.go

@@ -0,0 +1,128 @@
+package briefing
+
+import (
+	"fmt"
+	"math"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+func rangeLabel(value forecast.Range) string {
+	if value.Min == nil && value.Max == nil {
+		return ""
+	}
+	if value.Min != nil && value.Max != nil {
+		low := roundedInt(value.Min)
+		high := roundedInt(value.Max)
+		if low != nil && high != nil && *low == *high {
+			return fmt.Sprintf("%d", *low)
+		}
+		return fmt.Sprintf("%d-%d", *low, *high)
+	}
+	if value.Min != nil {
+		low := roundedInt(value.Min)
+		return fmt.Sprintf("%d", *low)
+	}
+	high := roundedInt(value.Max)
+	return fmt.Sprintf("%d", *high)
+}
+
+func daypartApparentRangeLabel(value forecast.Range) string {
+	if value.Min == nil && value.Max == nil {
+		return ""
+	}
+	return rangeLabel(value)
+}
+
+func roundedInt(value *float64) *int {
+	if value == nil {
+		return nil
+	}
+	rounded := int(*value + 0.5)
+	if *value < 0 {
+		rounded = int(*value - 0.5)
+	}
+	return &rounded
+}
+
+func windDirectionLabel(degrees *float64) string {
+	if degrees == nil {
+		return ""
+	}
+	labels := []string{"N", "NNE", "NE", "ENE", "E", "ESE", "SE", "SSE", "S", "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"}
+	normalized := math.Mod(*degrees, 360)
+	if normalized < 0 {
+		normalized += 360
+	}
+	sector := int(math.Floor((normalized+11.25)/22.5)) % len(labels)
+	return labels[sector]
+}
+
+func timedClockLabel(value *forecast.TimedValue, timezone string) string {
+	if value == nil {
+		return ""
+	}
+	return clockLabel(value.Time, timezone)
+}
+
+func periodClockLabel(period timeutil.Period, timezone string) string {
+	if !period.IsValid() {
+		return ""
+	}
+	return clockLabel(period.Start, timezone) + "-" + clockLabel(period.End, timezone)
+}
+
+func friendlyPeriodLabel(period timeutil.Period, timezone string) string {
+	if !period.IsValid() {
+		return ""
+	}
+	return friendlyDateTimeLabel(period.Start, timezone) + " to " + friendlyDateTimeLabel(period.End, timezone)
+}
+
+func friendlyDateTimeLabel(value time.Time, timezone string) string {
+	if value.IsZero() {
+		return ""
+	}
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		location = time.UTC
+	}
+	return value.In(location).Format("2006-01-02 at 3:04 PM")
+}
+
+func friendlyDateLabel(date string, timezone string) string {
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		location = time.UTC
+	}
+	parsed, err := time.ParseInLocation(timeutil.DateLayout, date, location)
+	if err != nil {
+		return date
+	}
+	return parsed.Format("Monday, January 2, 2006")
+}
+
+func localDateLabel(value time.Time, timezone string) string {
+	if value.IsZero() {
+		return ""
+	}
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		location = time.UTC
+	}
+	return value.In(location).Format(timeutil.DateLayout)
+}
+
+func clockLabel(value time.Time, timezone string) string {
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		location = time.UTC
+	}
+	label := value.In(location).Format("3 PM")
+	if label == "12 AM" && value.In(location).Minute() == 0 {
+		return "12 AM"
+	}
+	return label
+}

internal/briefing/module_format_helpers_test.go

@@ -0,0 +1,29 @@
+package briefing
+
+import "testing"
+
+func TestWindDirectionLabelUsesSixteenPointCompass(t *testing.T) {
+	tests := []struct {
+		name    string
+		degrees *float64
+		want    string
+	}{
+		{name: "nil", degrees: nil, want: ""},
+		{name: "north", degrees: floatPtr(0), want: "N"},
+		{name: "below first boundary", degrees: floatPtr(11.24), want: "N"},
+		{name: "at first boundary", degrees: floatPtr(11.25), want: "NNE"},
+		{name: "northeast", degrees: floatPtr(45), want: "NE"},
+		{name: "south", degrees: floatPtr(180), want: "S"},
+		{name: "wrap to north", degrees: floatPtr(348.75), want: "N"},
+		{name: "full rotation", degrees: floatPtr(360), want: "N"},
+		{name: "negative normalizes", degrees: floatPtr(-45), want: "NW"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := windDirectionLabel(tt.degrees); got != tt.want {
+				t.Fatalf("windDirectionLabel(%v) = %q, want %q", tt.degrees, got, tt.want)
+			}
+		})
+	}
+}

internal/briefing/modules.go

@@ -0,0 +1,363 @@
+package briefing
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+)
+
+type ModuleContext struct {
+	Resolved  report.Resolved
+	Collected facts.CollectedFacts
+	Derived   facts.DerivedFacts
+	Units     string
+	Timezone  string
+	Location  *LocationContext
+}
+
+type ModuleBuilder func(ModuleContext, any) (*module.Output, error)
+
+type ModuleDefinition struct {
+	ID                module.ID
+	StanzaName        string
+	DefaultOptions    any
+	RequiredCollected []module.FactRequirement
+	RequiredDerived   []module.FactRequirement
+	SupportedReports  []report.ID
+	MissingData       module.MissingDataBehavior
+	AllowDuplicate    bool
+	Builder           ModuleBuilder
+}
+
+type ModuleRegistry struct {
+	definitions map[module.ID]ModuleDefinition
+}
+
+func DefaultModuleRegistry() (ModuleRegistry, error) {
+	return NewModuleRegistry(defaultModuleDefinitions())
+}
+
+func MustDefaultModuleRegistry() ModuleRegistry {
+	registry, err := DefaultModuleRegistry()
+	if err != nil {
+		panic(err)
+	}
+	return registry
+}
+
+func NewModuleRegistry(definitions []ModuleDefinition) (ModuleRegistry, error) {
+	registry := ModuleRegistry{definitions: map[module.ID]ModuleDefinition{}}
+	seenStanzas := map[string]module.ID{}
+	for i, definition := range definitions {
+		if definition.ID == "" {
+			return ModuleRegistry{}, fmt.Errorf("module definition[%d].id is required", i)
+		}
+		if definition.StanzaName == "" {
+			return ModuleRegistry{}, fmt.Errorf("module %q stanza name is required", definition.ID)
+		}
+		if _, ok := registry.definitions[definition.ID]; ok {
+			return ModuleRegistry{}, fmt.Errorf("duplicate module definition %q", definition.ID)
+		}
+		if definition.Builder == nil {
+			return ModuleRegistry{}, fmt.Errorf("module %q has no builder", definition.ID)
+		}
+		if definition.MissingData == module.MissingDataWarn {
+			return ModuleRegistry{}, fmt.Errorf("module %q uses unsupported missing data behavior %q", definition.ID, definition.MissingData)
+		}
+		if existingID, ok := seenStanzas[definition.StanzaName]; ok {
+			return ModuleRegistry{}, fmt.Errorf("duplicate stanza name %q for modules %q and %q", definition.StanzaName, existingID, definition.ID)
+		}
+		seenStanzas[definition.StanzaName] = definition.ID
+		registry.definitions[definition.ID] = definition
+	}
+	return registry, nil
+}
+
+func (r ModuleRegistry) Lookup(id module.ID) (ModuleDefinition, error) {
+	definition, ok := r.definitions[id]
+	if !ok {
+		return ModuleDefinition{}, fmt.Errorf("unknown module %q", id)
+	}
+	return definition, nil
+}
+
+func (r ModuleRegistry) BuildModule(ctx ModuleContext, item module.ConfigItem) (*module.Output, error) {
+	definition, err := r.Lookup(item.ID)
+	if err != nil {
+		return nil, err
+	}
+	if !definition.SupportsReport(ctx.Resolved.Definition.ID) {
+		return nil, fmt.Errorf("module %q is not compatible with report %q", item.ID, ctx.Resolved.Definition.ID)
+	}
+	if err := definition.ValidateOptions(item.Options); err != nil {
+		return nil, err
+	}
+	if definition.Builder == nil {
+		return nil, fmt.Errorf("module %q has no builder", item.ID)
+	}
+	missing := missingRequirements(definition, ctx)
+	if len(missing) > 0 {
+		switch definition.MissingData {
+		case module.MissingDataOmit:
+			return nil, nil
+		case module.MissingDataError:
+			return nil, fmt.Errorf("module %q missing required facts: %s", item.ID, strings.Join(missing, ", "))
+		case module.MissingDataEmpty:
+		case module.MissingDataWarn:
+			return nil, fmt.Errorf("module %q uses unsupported missing data behavior %q", item.ID, definition.MissingData)
+		default:
+			return nil, fmt.Errorf("module %q has unknown missing data behavior %q", item.ID, definition.MissingData)
+		}
+	}
+	options := item.Options
+	if options == nil {
+		options = definition.DefaultOptions
+	}
+	output, err := definition.Builder(ctx, options)
+	if err != nil {
+		return nil, err
+	}
+	if output == nil {
+		return nil, nil
+	}
+	if output.ID != definition.ID {
+		return nil, fmt.Errorf("module %q produced output id %q", definition.ID, output.ID)
+	}
+	if output.StanzaName != definition.StanzaName {
+		return nil, fmt.Errorf("module %q produced stanza %q, want %q", definition.ID, output.StanzaName, definition.StanzaName)
+	}
+	return output, nil
+}
+
+func missingRequirements(definition ModuleDefinition, ctx ModuleContext) []string {
+	var missing []string
+	for _, requirement := range definition.RequiredCollected {
+		if !collectedFactAvailable(requirement, ctx) {
+			missing = append(missing, string(requirement))
+		}
+	}
+	for _, requirement := range definition.RequiredDerived {
+		if !derivedFactAvailable(requirement, ctx) {
+			missing = append(missing, string(requirement))
+		}
+	}
+	return missing
+}
+
+func collectedFactAvailable(requirement module.FactRequirement, ctx ModuleContext) bool {
+	switch requirement {
+	case module.CollectedCurrentConditions:
+		return ctx.Collected.Current != nil
+	case module.CollectedNarrativeForecast:
+		return ctx.Collected.Narrative != nil
+	case module.CollectedHourlyForecast:
+		return ctx.Collected.Hourly != nil
+	case module.CollectedAlerts:
+		return ctx.Collected.Alerts != nil
+	case module.CollectedDiscussion:
+		return ctx.Collected.Discussion != nil
+	case module.CollectedWeatherStory:
+		return ctx.Collected.WeatherStory != nil
+	case module.CollectedSourceMetadata:
+		return len(ctx.Collected.SourceProvenance) > 0 || len(ctx.Collected.SourceWarnings) > 0
+	default:
+		return false
+	}
+}
+
+func derivedFactAvailable(requirement module.FactRequirement, ctx ModuleContext) bool {
+	switch requirement {
+	case module.RequiresDerivedHourlyPeriods:
+		return len(ctx.Derived.ValidPeriodHourlyPeriods) > 0
+	case module.RequiresDerivedNarrativePeriods:
+		return len(ctx.Derived.ValidPeriodNarrativePeriods) > 0
+	case module.RequiresDerivedAlertOverlaps:
+		return true
+	case module.RequiresDerivedDailySummaries:
+		return len(ctx.Derived.DailySummaries) > 0
+	case module.RequiresDerivedDaypartSummaries:
+		return len(ctx.Derived.DaypartSummaries) > 0
+	case module.RequiresDerivedPrecipTiming:
+		return true
+	default:
+		return false
+	}
+}
+
+func (r ModuleRegistry) ValidateComposition(reportID report.ID, items []module.ConfigItem) error {
+	seenModules := map[module.ID]struct{}{}
+	seenStanzas := map[string]module.ID{}
+	for i, item := range items {
+		definition, err := r.Lookup(item.ID)
+		if err != nil {
+			return fmt.Errorf("modules[%d]: %w", i, err)
+		}
+		if _, ok := seenModules[item.ID]; ok && !definition.AllowDuplicate {
+			return fmt.Errorf("modules[%d]: duplicate module %q", i, item.ID)
+		}
+		seenModules[item.ID] = struct{}{}
+		if existingID, ok := seenStanzas[definition.StanzaName]; ok {
+			return fmt.Errorf("modules[%d]: duplicate stanza name %q for modules %q and %q", i, definition.StanzaName, existingID, item.ID)
+		}
+		seenStanzas[definition.StanzaName] = item.ID
+		if !definition.SupportsReport(reportID) {
+			return fmt.Errorf("modules[%d]: module %q is not compatible with report %q", i, item.ID, reportID)
+		}
+		if err := definition.ValidateOptions(item.Options); err != nil {
+			return fmt.Errorf("modules[%d]: %w", i, err)
+		}
+	}
+	return nil
+}
+
+func (d ModuleDefinition) SupportsReport(id report.ID) bool {
+	if len(d.SupportedReports) == 0 {
+		return true
+	}
+	for _, supported := range d.SupportedReports {
+		if supported == id {
+			return true
+		}
+	}
+	return false
+}
+
+func (d ModuleDefinition) ValidateOptions(options any) error {
+	if options == nil {
+		return nil
+	}
+	if d.DefaultOptions == nil {
+		return fmt.Errorf("module %q does not accept options", d.ID)
+	}
+	want := reflect.TypeOf(d.DefaultOptions)
+	got := reflect.TypeOf(options)
+	if got == want {
+		return nil
+	}
+	if got.Kind() == reflect.Pointer && got.Elem() == want {
+		return nil
+	}
+	return fmt.Errorf("module %q options have type %s, want %s", d.ID, got, want)
+}
+
+func defaultModuleDefinitions() []ModuleDefinition {
+	allReports := []report.ID{report.DailyToday, report.DailyTomorrow, report.ThreeDay, report.Weekend, report.Storm}
+	daypartReports := []report.ID{report.DailyToday, report.DailyTomorrow, report.ThreeDay, report.Weekend}
+	return []ModuleDefinition{
+		{
+			ID:                module.Metadata,
+			StanzaName:        "metadata",
+			DefaultOptions:    module.MetadataOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedSourceMetadata},
+			SupportedReports:  allReports,
+			MissingData:       module.MissingDataEmpty,
+			Builder:           buildMetadataModule,
+		},
+		{
+			ID:                module.CurrentConditions,
+			StanzaName:        "current_conditions",
+			DefaultOptions:    module.CurrentConditionsOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedCurrentConditions},
+			SupportedReports:  allReports,
+			MissingData:       module.MissingDataOmit,
+			Builder:           buildCurrentConditionsModule,
+		},
+		{
+			ID:                module.NarrativeForecast,
+			StanzaName:        "narrative_forecast",
+			DefaultOptions:    module.NarrativeForecastOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedNarrativeForecast},
+			RequiredDerived:   []module.FactRequirement{module.RequiresDerivedNarrativePeriods},
+			SupportedReports:  []report.ID{report.DailyToday, report.DailyTomorrow},
+			MissingData:       module.MissingDataOmit,
+			Builder:           buildNarrativeForecastModule,
+		},
+		{
+			ID:                module.HourlyForecast,
+			StanzaName:        "hourly_forecast",
+			DefaultOptions:    module.HourlyForecastOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedHourlyForecast},
+			RequiredDerived:   []module.FactRequirement{module.RequiresDerivedHourlyPeriods},
+			SupportedReports:  []report.ID{report.DailyToday, report.DailyTomorrow},
+			MissingData:       module.MissingDataOmit,
+			Builder:           buildHourlyForecastModule,
+		},
+		{
+			ID:               module.DerivedDailySummary,
+			StanzaName:       "derived_daily_summary",
+			DefaultOptions:   module.DerivedDailySummaryOptions{},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDailySummaries, module.RequiresDerivedPrecipTiming},
+			SupportedReports: []report.ID{report.DailyToday, report.DailyTomorrow},
+			MissingData:      module.MissingDataError,
+			Builder:          buildDerivedDailySummaryModule,
+		},
+		{
+			ID:               module.DerivedDaypartSummaries,
+			StanzaName:       "derived_daypart_summaries",
+			DefaultOptions:   module.DerivedDaypartSummariesOptions{},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDaypartSummaries},
+			SupportedReports: daypartReports,
+			MissingData:      module.MissingDataError,
+			Builder:          buildDerivedDaypartSummariesModule,
+		},
+		{
+			ID:               module.PrecipTiming,
+			StanzaName:       "precip_timing",
+			DefaultOptions:   module.PrecipTimingOptions{},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDaypartSummaries},
+			SupportedReports: allReports,
+			MissingData:      module.MissingDataEmpty,
+			Builder:          buildPrecipTimingModule,
+		},
+		{
+			ID:                module.AlertDigest,
+			StanzaName:        "alert_digest",
+			DefaultOptions:    module.AlertDigestOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedAlerts},
+			RequiredDerived:   []module.FactRequirement{module.RequiresDerivedAlertOverlaps},
+			SupportedReports:  allReports,
+			MissingData:       module.MissingDataEmpty,
+			Builder:           buildAlertDigestModule,
+		},
+		{
+			ID:                module.AreaForecastDiscussion,
+			StanzaName:        "area_forecast_discussion",
+			DefaultOptions:    module.AreaForecastDiscussionOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedDiscussion},
+			SupportedReports:  allReports,
+			MissingData:       module.MissingDataOmit,
+			Builder:           buildAreaForecastDiscussionModule,
+		},
+		{
+			ID:                module.WeatherStory,
+			StanzaName:        "weather_story",
+			DefaultOptions:    module.WeatherStoryOptions{},
+			RequiredCollected: []module.FactRequirement{module.CollectedWeatherStory},
+			SupportedReports:  allReports,
+			MissingData:       module.MissingDataOmit,
+			Builder:           buildWeatherStoryModule,
+		},
+		{
+			ID:               module.OutdoorWindows,
+			StanzaName:       "outdoor_windows",
+			DefaultOptions:   module.OutdoorWindowsOptions{},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDaypartSummaries},
+			SupportedReports: daypartReports,
+			MissingData:      module.MissingDataEmpty,
+			Builder:          buildOutdoorWindowsModule,
+		},
+		{
+			ID:               module.TomorrowPlanning,
+			StanzaName:       "tomorrow_planning",
+			DefaultOptions:   module.TomorrowPlanningOptions{},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDailySummaries},
+			SupportedReports: []report.ID{report.DailyTomorrow},
+			MissingData:      module.MissingDataEmpty,
+			Builder:          buildTomorrowPlanningModule,
+		},
+	}
+}

internal/briefing/modules_test.go

@@ -0,0 +1,133 @@
+package briefing
+
+import (
+	"strings"
+	"testing"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+)
+
+func TestDefaultModuleRegistryValidatesReportDefaults(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	for _, definition := range report.DefaultRegistry().All() {
+		if err := registry.ValidateComposition(definition.ID, definition.Modules); err != nil {
+			t.Fatalf("ValidateComposition(%s) error = %v", definition.ID, err)
+		}
+		for _, item := range definition.Modules {
+			moduleDefinition, err := registry.Lookup(item.ID)
+			if err != nil {
+				t.Fatalf("Lookup(%s) error = %v", item.ID, err)
+			}
+			if moduleDefinition.Builder == nil {
+				t.Fatalf("report %s module %s has no builder", definition.ID, item.ID)
+			}
+		}
+	}
+}
+
+func TestDefaultReportModulesBuildSnapshots(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	for _, definition := range report.DefaultRegistry().All() {
+		t.Run(string(definition.ID), func(t *testing.T) {
+			ctx := derivedModuleContext(definition.ID)
+			var outputs []module.Output
+			for _, item := range definition.Modules {
+				output, err := registry.BuildModule(ctx, item)
+				if err != nil {
+					t.Fatalf("BuildModule(%s) error = %v", item.ID, err)
+				}
+				if output != nil {
+					outputs = append(outputs, *output)
+				}
+			}
+			snapshot, err := module.NewSnapshot(outputs)
+			if err != nil {
+				t.Fatalf("NewSnapshot() error = %v", err)
+			}
+			if len(snapshot.Outputs) == 0 {
+				t.Fatal("snapshot outputs = 0, want default report modules")
+			}
+		})
+	}
+}
+
+func TestModuleRegistryRejectsUnknownModule(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	err := registry.ValidateComposition(report.DailyToday, []module.ConfigItem{{ID: module.ID("unknown")}})
+	if err == nil || !strings.Contains(err.Error(), `unknown module "unknown"`) {
+		t.Fatalf("error = %v, want unknown module", err)
+	}
+}
+
+func TestModuleRegistryRejectsDuplicateModuleIDs(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	err := registry.ValidateComposition(report.DailyToday, []module.ConfigItem{
+		{ID: module.Metadata},
+		{ID: module.Metadata},
+	})
+	if err == nil || !strings.Contains(err.Error(), `duplicate module "metadata"`) {
+		t.Fatalf("error = %v, want duplicate module", err)
+	}
+}
+
+func TestModuleRegistryRejectsDuplicateStanzaNames(t *testing.T) {
+	_, err := NewModuleRegistry([]ModuleDefinition{
+		{ID: module.Metadata, StanzaName: "metadata", DefaultOptions: module.MetadataOptions{}, Builder: noopModuleBuilder},
+		{ID: module.CurrentConditions, StanzaName: "metadata", DefaultOptions: module.CurrentConditionsOptions{}, Builder: noopModuleBuilder},
+	})
+	if err == nil || !strings.Contains(err.Error(), `duplicate stanza name "metadata"`) {
+		t.Fatalf("error = %v, want duplicate stanza name", err)
+	}
+}
+
+func TestModuleRegistryRejectsIncompatibleReports(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	err := registry.ValidateComposition(report.DailyToday, []module.ConfigItem{{ID: module.TomorrowPlanning}})
+	if err == nil || !strings.Contains(err.Error(), `module "tomorrow_planning" is not compatible with report "daily_today"`) {
+		t.Fatalf("error = %v, want incompatible report", err)
+	}
+}
+
+func TestModuleRegistryRejectsDefinitionsWithoutBuilders(t *testing.T) {
+	_, err := NewModuleRegistry([]ModuleDefinition{
+		{ID: module.Metadata, StanzaName: "metadata", DefaultOptions: module.MetadataOptions{}},
+	})
+	if err == nil || !strings.Contains(err.Error(), `module "metadata" has no builder`) {
+		t.Fatalf("error = %v, want missing builder", err)
+	}
+}
+
+func TestModuleRegistryRejectsUnsupportedMissingDataWarn(t *testing.T) {
+	_, err := NewModuleRegistry([]ModuleDefinition{
+		{ID: module.Metadata, StanzaName: "metadata", DefaultOptions: module.MetadataOptions{}, MissingData: module.MissingDataWarn, Builder: noopModuleBuilder},
+	})
+	if err == nil || !strings.Contains(err.Error(), `unsupported missing data behavior`) {
+		t.Fatalf("error = %v, want unsupported missing-data behavior", err)
+	}
+}
+
+func TestModuleRegistryRejectsInvalidOptionShapes(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	err := registry.ValidateComposition(report.DailyToday, []module.ConfigItem{
+		{ID: module.Metadata, Options: module.CurrentConditionsOptions{}},
+	})
+	if err == nil || !strings.Contains(err.Error(), `module "metadata" options have type module.CurrentConditionsOptions, want module.MetadataOptions`) {
+		t.Fatalf("error = %v, want invalid option shape", err)
+	}
+}
+
+func TestModuleRegistryAcceptsTypedOptions(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	err := registry.ValidateComposition(report.DailyToday, []module.ConfigItem{
+		{ID: module.Metadata, Options: module.MetadataOptions{}},
+		{ID: module.CurrentConditions, Options: &module.CurrentConditionsOptions{}},
+	})
+	if err != nil {
+		t.Fatalf("ValidateComposition() error = %v", err)
+	}
+}
+
+func noopModuleBuilder(ModuleContext, any) (*module.Output, error) {
+	return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: struct{}{}}, nil
+}

internal/briefing/narrative_forecast_module.go

@@ -0,0 +1,91 @@
+package briefing
+
+import (
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type NarrativeForecastModule struct {
+	Product          string                    `json:"product,omitempty"`
+	IssuedAt         time.Time                 `json:"issued_at,omitempty"`
+	UpdatedAt        *time.Time                `json:"updated_at,omitempty"`
+	SourceLocation   string                    `json:"source_location,omitempty"`
+	SourceLocationID string                    `json:"source_location_id,omitempty"`
+	Periods          []NarrativeForecastPeriod `json:"periods,omitempty"`
+}
+
+type NarrativeForecastPeriod struct {
+	Name                              string   `json:"name,omitempty"`
+	StartTime                         string   `json:"start_time,omitempty"`
+	EndTime                           string   `json:"end_time,omitempty"`
+	IsDay                             *bool    `json:"is_day,omitempty"`
+	TextDescription                   string   `json:"text_description,omitempty"`
+	TemperatureC                      *float64 `json:"temperature_c,omitempty"`
+	TemperatureF                      *float64 `json:"temperature_f,omitempty"`
+	TemperatureCMin                   *float64 `json:"temperature_c_min,omitempty"`
+	TemperatureFMin                   *float64 `json:"temperature_f_min,omitempty"`
+	TemperatureCMax                   *float64 `json:"temperature_c_max,omitempty"`
+	TemperatureFMax                   *float64 `json:"temperature_f_max,omitempty"`
+	WindSpeedKmh                      *float64 `json:"wind_speed_kmh,omitempty"`
+	WindSpeedMph                      *float64 `json:"wind_speed_mph,omitempty"`
+	WindGustKmh                       *float64 `json:"wind_gust_kmh,omitempty"`
+	WindGustMph                       *float64 `json:"wind_gust_mph,omitempty"`
+	WindDirection                     string   `json:"wind_direction,omitempty"`
+	ProbabilityOfPrecipitationPercent *float64 `json:"probability_of_precipitation_percent,omitempty"`
+}
+
+func buildNarrativeForecastModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	narrative := ctx.Collected.Narrative
+	if narrative == nil || len(ctx.Derived.ValidPeriodNarrativePeriods) == 0 {
+		return nil, nil
+	}
+	value := NarrativeForecastModule{
+		Product:          narrative.Product,
+		IssuedAt:         narrative.IssuedAt,
+		UpdatedAt:        copyTime(narrative.UpdatedAt),
+		SourceLocation:   narrative.LocationName,
+		SourceLocationID: narrative.LocationID,
+		Periods:          narrativeForecastPeriods(ctx.Derived.ValidPeriodNarrativePeriods, ctx.Timezone),
+	}
+	if value.isEmpty() {
+		return nil, nil
+	}
+	return &module.Output{ID: module.NarrativeForecast, StanzaName: "narrative_forecast", Value: value}, nil
+}
+
+func narrativeForecastPeriods(periods []weatherdata.ForecastPeriod, timezone string) []NarrativeForecastPeriod {
+	out := make([]NarrativeForecastPeriod, 0, len(periods))
+	for _, period := range periods {
+		out = append(out, NarrativeForecastPeriod{
+			Name:                              period.Name,
+			StartTime:                         friendlyDateTimeLabel(period.StartTime, timezone),
+			EndTime:                           friendlyDateTimeLabel(period.EndTime, timezone),
+			IsDay:                             copyBool(period.IsDay),
+			TextDescription:                   period.TextDescription,
+			TemperatureC:                      copyFloat(period.TemperatureC),
+			TemperatureF:                      copyFloat(period.TemperatureF),
+			TemperatureCMin:                   copyFloat(period.TemperatureCMin),
+			TemperatureFMin:                   copyFloat(period.TemperatureFMin),
+			TemperatureCMax:                   copyFloat(period.TemperatureCMax),
+			TemperatureFMax:                   copyFloat(period.TemperatureFMax),
+			WindSpeedKmh:                      copyFloat(period.WindSpeedKmh),
+			WindSpeedMph:                      copyFloat(period.WindSpeedMph),
+			WindGustKmh:                       copyFloat(period.WindGustKmh),
+			WindGustMph:                       copyFloat(period.WindGustMph),
+			WindDirection:                     windDirectionLabel(period.WindDirectionDegrees),
+			ProbabilityOfPrecipitationPercent: copyFloat(period.ProbabilityOfPrecipitationPercent),
+		})
+	}
+	return out
+}
+
+func (v NarrativeForecastModule) isEmpty() bool {
+	return v.Product == "" &&
+		v.IssuedAt.IsZero() &&
+		v.UpdatedAt == nil &&
+		v.SourceLocation == "" &&
+		v.SourceLocationID == "" &&
+		len(v.Periods) == 0
+}

internal/briefing/outdoor_windows_module.go

@@ -0,0 +1,38 @@
+package briefing
+
+import "gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+
+type OutdoorWindowsModule struct {
+	Best  *OutdoorWindowModule `json:"best,omitempty"`
+	Worst *OutdoorWindowModule `json:"worst,omitempty"`
+}
+
+type OutdoorWindowModule struct {
+	Daypart string   `json:"daypart"`
+	Start   string   `json:"start"`
+	End     string   `json:"end"`
+	Reasons []string `json:"reasons,omitempty"`
+	Score   float64  `json:"score"`
+}
+
+func buildOutdoorWindowsModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	windows := buildOutdoorWindows(ctx.Derived.DaypartSummaries)
+	value := OutdoorWindowsModule{
+		Best:  outdoorWindowValue(windows.Best),
+		Worst: outdoorWindowValue(windows.Worst),
+	}
+	return &module.Output{ID: module.OutdoorWindows, StanzaName: "outdoor_windows", Value: value}, nil
+}
+
+func outdoorWindowValue(window *OutdoorWindow) *OutdoorWindowModule {
+	if window == nil {
+		return nil
+	}
+	return &OutdoorWindowModule{
+		Daypart: window.Daypart,
+		Start:   window.Start,
+		End:     window.End,
+		Reasons: append([]string(nil), window.Reasons...),
+		Score:   window.Score,
+	}
+}

internal/briefing/package.go

@@ -0,0 +1,195 @@
+// Package briefing builds prompt-facing module values.
+package briefing
+
+import (
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type Metadata struct {
+	RunID            string                      `json:"runId"`
+	ReportID         report.ID                   `json:"reportId"`
+	Variant          string                      `json:"variant,omitempty"`
+	PromptID         string                      `json:"promptId"`
+	GeneratedAt      time.Time                   `json:"generatedAt"`
+	Units            string                      `json:"units"`
+	Timezone         string                      `json:"timezone"`
+	ValidPeriod      timeutil.Period             `json:"validPeriod"`
+	Location         *LocationContext            `json:"location,omitempty"`
+	SourceLocationID string                      `json:"sourceLocationId,omitempty"`
+	SourceLocation   string                      `json:"sourceLocation,omitempty"`
+	Sources          []SourceMetadata            `json:"sources,omitempty"`
+	SourceWarnings   []weatherdata.SourceWarning `json:"sourceWarnings,omitempty"`
+	Alerts           *AlertStatus                `json:"alerts,omitempty"`
+}
+
+type LocationContext struct {
+	ID       string `json:"id,omitempty"`
+	Name     string `json:"name,omitempty"`
+	Region   string `json:"region,omitempty"`
+	Timezone string `json:"timezone,omitempty"`
+}
+
+type SourceMetadata struct {
+	Name       string                      `json:"name"`
+	Endpoint   string                      `json:"endpoint,omitempty"`
+	FetchedAt  time.Time                   `json:"fetchedAt"`
+	IssuedAt   *time.Time                  `json:"issuedAt,omitempty"`
+	UpdatedAt  *time.Time                  `json:"updatedAt,omitempty"`
+	DataSHA256 string                      `json:"dataSha256,omitempty"`
+	Missing    bool                        `json:"missing,omitempty"`
+	Warnings   []weatherdata.SourceWarning `json:"warnings,omitempty"`
+}
+
+type AlertStatus struct {
+	Checked       bool `json:"checked"`
+	ActiveCount   int  `json:"activeCount"`
+	RelevantCount int  `json:"relevantCount"`
+	Missing       bool `json:"missing,omitempty"`
+}
+
+type BuildContext struct {
+	Resolved report.Resolved
+	Bundle   *weatherdata.Bundle
+	Units    string
+	Timezone string
+	Location *LocationContext
+}
+
+func BuildMetadata(ctx BuildContext) Metadata {
+	metadata := ctx.Resolved.Metadata()
+	sourceLocationID, sourceLocation := sourceLocation(ctx.Bundle)
+	return Metadata{
+		RunID:            metadata.RunID,
+		ReportID:         metadata.ReportID,
+		Variant:          variantForReport(metadata.ReportID),
+		PromptID:         metadata.PromptID,
+		GeneratedAt:      metadata.GeneratedAt,
+		Units:            ctx.Units,
+		Timezone:         ctx.Timezone,
+		ValidPeriod:      metadata.ValidPeriod,
+		Location:         copyLocation(ctx.Location),
+		SourceLocationID: sourceLocationID,
+		SourceLocation:   sourceLocation,
+		Sources:          sourceMetadata(ctx.Bundle),
+		SourceWarnings:   sourceWarnings(ctx.Bundle),
+		Alerts:           alertStatus(ctx.Bundle),
+	}
+}
+
+func copyLocation(location *LocationContext) *LocationContext {
+	if location == nil {
+		return nil
+	}
+	copied := *location
+	return &copied
+}
+
+func copyBool(value *bool) *bool {
+	if value == nil {
+		return nil
+	}
+	copied := *value
+	return &copied
+}
+
+func copyInt(value *int) *int {
+	if value == nil {
+		return nil
+	}
+	copied := *value
+	return &copied
+}
+
+func copyFloat(value *float64) *float64 {
+	if value == nil {
+		return nil
+	}
+	copied := *value
+	return &copied
+}
+
+func copyTime(value *time.Time) *time.Time {
+	if value == nil {
+		return nil
+	}
+	copied := *value
+	return &copied
+}
+
+func sourceLocation(bundle *weatherdata.Bundle) (string, string) {
+	if bundle == nil {
+		return "", ""
+	}
+	for _, run := range []*weatherdata.ForecastRun{bundle.Hourly, bundle.Narrative, bundle.Daily} {
+		if run == nil {
+			continue
+		}
+		if run.LocationID != "" || run.LocationName != "" {
+			return run.LocationID, run.LocationName
+		}
+	}
+	return "", ""
+}
+
+func sourceMetadata(bundle *weatherdata.Bundle) []SourceMetadata {
+	if bundle == nil {
+		return nil
+	}
+	out := make([]SourceMetadata, 0, len(bundle.Sources))
+	for _, source := range bundle.Sources {
+		out = append(out, SourceMetadata{
+			Name:       source.Name,
+			Endpoint:   source.Endpoint,
+			FetchedAt:  source.FetchedAt,
+			IssuedAt:   source.IssuedAt,
+			UpdatedAt:  source.UpdatedAt,
+			DataSHA256: source.DataSHA256,
+			Missing:    source.Missing,
+			Warnings:   source.Warnings,
+		})
+	}
+	return out
+}
+
+func sourceWarnings(bundle *weatherdata.Bundle) []weatherdata.SourceWarning {
+	if bundle == nil {
+		return nil
+	}
+	return bundle.Warnings
+}
+
+func alertStatus(bundle *weatherdata.Bundle) *AlertStatus {
+	if bundle == nil {
+		return nil
+	}
+	status := &AlertStatus{}
+	if bundle.Alerts != nil {
+		status.Checked = true
+		status.ActiveCount = len(bundle.Alerts.Alerts)
+	}
+	for _, source := range bundle.Sources {
+		if source.Name == "alerts" && source.Missing {
+			status.Missing = true
+			break
+		}
+	}
+	if !status.Checked && !status.Missing {
+		return nil
+	}
+	return status
+}
+
+func variantForReport(id report.ID) string {
+	switch id {
+	case report.DailyToday:
+		return "today"
+	case report.DailyTomorrow:
+		return "tomorrow"
+	default:
+		return ""
+	}
+}

internal/briefing/precip_timing_module.go

@@ -0,0 +1,49 @@
+package briefing
+
+import (
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+type PrecipTimingModule struct {
+	MaxPopPercent        *int                        `json:"max_pop_percent,omitempty"`
+	MaxPopTime           string                      `json:"max_pop_time,omitempty"`
+	ProbabilityThreshold float64                     `json:"probability_threshold"`
+	PrecipitationWindows []PrecipitationWindowModule `json:"precipitation_windows,omitempty"`
+	ThunderMentioned     bool                        `json:"thunder_mentioned"`
+}
+
+type PrecipitationWindowModule struct {
+	Start         string `json:"start"`
+	End           string `json:"end,omitempty"`
+	MaxPopPercent *int   `json:"max_pop_percent,omitempty"`
+	MaxPopTime    string `json:"max_pop_time,omitempty"`
+}
+
+func buildPrecipTimingModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	value := precipTimingValue(ctx.Derived.PrecipTiming, ctx.Timezone)
+	return &module.Output{ID: module.PrecipTiming, StanzaName: "precip_timing", Value: value}, nil
+}
+
+func precipTimingValue(timing forecast.PrecipTiming, timezone string) PrecipTimingModule {
+	value := PrecipTimingModule{
+		ProbabilityThreshold: timing.ProbabilityThreshold,
+		ThunderMentioned:     timing.ThunderMentioned,
+	}
+	if timing.MaxPrecipitationProbability != nil {
+		value.MaxPopPercent = roundedInt(&timing.MaxPrecipitationProbability.Value)
+		value.MaxPopTime = clockLabel(timing.MaxPrecipitationProbability.Time, timezone)
+	}
+	for _, window := range timing.PrecipitationWindows {
+		item := PrecipitationWindowModule{
+			Start: clockLabel(window.Start, timezone),
+		}
+		if window.End != nil {
+			item.End = clockLabel(*window.End, timezone)
+		}
+		item.MaxPopPercent = roundedInt(&window.MaxPrecipitationProbability.Value)
+		item.MaxPopTime = clockLabel(window.MaxPrecipitationProbability.Time, timezone)
+		value.PrecipitationWindows = append(value.PrecipitationWindows, item)
+	}
+	return value
+}

internal/briefing/summary_helpers.go

@@ -0,0 +1,293 @@
+package briefing
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+)
+
+type OutdoorWindows struct {
+	Best  *OutdoorWindow
+	Worst *OutdoorWindow
+}
+
+type OutdoorWindow struct {
+	Daypart string
+	Start   string
+	End     string
+	Reasons []string
+	Score   float64
+}
+
+type TomorrowPlanning struct {
+	MorningReadiness             []string
+	CommuteSchoolWorkdayConcerns []string
+	OvernightChangeWatch         []string
+}
+
+func buildOutdoorWindows(dayparts []forecast.DaypartSummary) OutdoorWindows {
+	var best *OutdoorWindow
+	var worst *OutdoorWindow
+	for _, daypart := range dayparts {
+		if len(daypart.HourlyPeriods) == 0 {
+			continue
+		}
+		window := scoreOutdoorWindow(daypart)
+		if best == nil || window.Score < best.Score {
+			copied := window
+			best = &copied
+		}
+		if worst == nil || window.Score > worst.Score {
+			copied := window
+			worst = &copied
+		}
+	}
+	return OutdoorWindows{Best: best, Worst: worst}
+}
+
+func buildTomorrowPlanning(summary *forecast.DailySummary) *TomorrowPlanning {
+	planning := &TomorrowPlanning{}
+	morning := daypartNamed(summary.Dayparts, "morning")
+	if morning != nil {
+		planning.MorningReadiness = append(planning.MorningReadiness, readinessNotes(*morning)...)
+	}
+	if len(planning.MorningReadiness) == 0 {
+		planning.MorningReadiness = append(planning.MorningReadiness, "Morning weather looks routine based on the available hourly forecast.")
+	}
+
+	for _, daypart := range summary.Dayparts {
+		if daypart.Name == "overnight" || daypart.Name == "evening" {
+			continue
+		}
+		planning.CommuteSchoolWorkdayConcerns = appendUnique(planning.CommuteSchoolWorkdayConcerns, concernNotes(daypart)...)
+	}
+	for _, alert := range summary.AlertOverlaps {
+		if alert.Event != "" {
+			planning.CommuteSchoolWorkdayConcerns = appendUnique(planning.CommuteSchoolWorkdayConcerns, "Active alert to plan around: "+alert.Event+".")
+		}
+	}
+	if len(planning.CommuteSchoolWorkdayConcerns) == 0 {
+		planning.CommuteSchoolWorkdayConcerns = append(planning.CommuteSchoolWorkdayConcerns, "No major commute, school, or workday weather concerns stand out in the available forecast.")
+	}
+
+	overnight := daypartNamed(summary.Dayparts, "overnight")
+	if overnight != nil {
+		planning.OvernightChangeWatch = append(planning.OvernightChangeWatch, overnightWatchNotes(*overnight)...)
+	}
+	if len(planning.OvernightChangeWatch) == 0 {
+		planning.OvernightChangeWatch = append(planning.OvernightChangeWatch, "Watch for forecast timing or intensity adjustments overnight.")
+	}
+
+	return planning
+}
+
+func readinessNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 50 {
+		notes = append(notes, fmt.Sprintf("Morning precipitation chance peaks near %.0f%%.", daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Morning gusts may reach %.0f mph.", daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, "Morning wintry weather could affect surfaces and travel.")
+	}
+	if daypart.Indicators.Fog {
+		notes = append(notes, "Morning fog could reduce visibility.")
+	}
+	if daypart.Temperature.Min != nil && *daypart.Temperature.Min <= 32 {
+		notes = append(notes, "Morning temperatures may be at or below freezing.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func concernNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	prefix := titleWord(daypart.Name)
+	if prefix == "" {
+		prefix = "Daytime"
+	}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 40 {
+		notes = append(notes, fmt.Sprintf("%s precipitation chance reaches %.0f%%.", prefix, daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("%s gusts may reach %.0f mph.", prefix, daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, prefix+" wintry weather may affect travel.")
+	}
+	if daypart.Indicators.Heat {
+		notes = append(notes, prefix+" heat may require extra hydration and breaks.")
+	}
+	if daypart.Indicators.Cold {
+		notes = append(notes, prefix+" cold may require extra layers.")
+	}
+	if len(daypart.AlertOverlaps) > 0 {
+		notes = append(notes, prefix+" alert overlap needs attention.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func overnightWatchNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Overnight precipitation timing may shift; current peak is near %.0f%%.", daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Overnight gusts may reach %.0f mph before morning plans begin.", daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, "Overnight wintry weather could leave morning travel impacts.")
+	}
+	if len(daypart.AlertOverlaps) > 0 {
+		notes = append(notes, "Overnight alert timing could affect the morning setup.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func daypartNamed(dayparts []forecast.DaypartSummary, name string) *forecast.DaypartSummary {
+	for i := range dayparts {
+		if strings.EqualFold(dayparts[i].Name, name) {
+			return &dayparts[i]
+		}
+	}
+	return nil
+}
+
+func scoreOutdoorWindow(daypart forecast.DaypartSummary) OutdoorWindow {
+	score := 0.0
+	reasons := []string{}
+	if daypart.MaxPrecipitationProbability != nil {
+		score += daypart.MaxPrecipitationProbability.Value
+		if daypart.MaxPrecipitationProbability.Value >= 50 {
+			reasons = append(reasons, "high precipitation chance")
+		}
+	}
+	if daypart.PeakWindGust != nil {
+		score += daypart.PeakWindGust.Value * 1.5
+		if daypart.PeakWindGust.Value >= 30 {
+			reasons = append(reasons, "gusty wind")
+		}
+	}
+	if len(daypart.AlertOverlaps) > 0 {
+		score += float64(len(daypart.AlertOverlaps)) * 100
+		reasons = append(reasons, "alert overlap")
+	}
+	if daypart.Indicators.Heat || daypart.Indicators.Cold {
+		score += 25
+		if daypart.Indicators.Heat {
+			reasons = append(reasons, "heat risk")
+		}
+		if daypart.Indicators.Cold {
+			reasons = append(reasons, "cold risk")
+		}
+	}
+	if len(reasons) == 0 {
+		reasons = append(reasons, "quiet weather")
+	}
+	return OutdoorWindow{
+		Daypart: daypart.Name,
+		Start:   daypart.Period.Start.Format("15:04"),
+		End:     daypart.Period.End.Format("15:04"),
+		Reasons: dedupe(reasons),
+		Score:   math.Round(score*10) / 10,
+	}
+}
+
+func hazardsForIndicators(indicators forecast.Indicators) []string {
+	var hazards []string
+	if indicators.Snow {
+		hazards = append(hazards, "snow")
+	}
+	if indicators.Ice {
+		hazards = append(hazards, "ice")
+	}
+	if indicators.Fog {
+		hazards = append(hazards, "fog")
+	}
+	if indicators.Heat {
+		hazards = append(hazards, "heat")
+	}
+	if indicators.Cold {
+		hazards = append(hazards, "cold")
+	}
+	if indicators.Wind {
+		hazards = append(hazards, "wind")
+	}
+	return hazards
+}
+
+func addRange(target *forecast.Range, value forecast.Range) {
+	if value.Min != nil {
+		if target.Min == nil || *value.Min < *target.Min {
+			copied := *value.Min
+			target.Min = &copied
+		}
+	}
+	if value.Max != nil {
+		if target.Max == nil || *value.Max > *target.Max {
+			copied := *value.Max
+			target.Max = &copied
+		}
+	}
+}
+
+func maxTimedValue(target **forecast.TimedValue, value *forecast.TimedValue) {
+	if value == nil {
+		return
+	}
+	if *target == nil || value.Value > (*target).Value {
+		copied := *value
+		*target = &copied
+	}
+}
+
+func sortedSet(values map[string]struct{}) []string {
+	out := make([]string, 0, len(values))
+	for value := range values {
+		out = append(out, value)
+	}
+	sort.Strings(out)
+	return out
+}
+
+func dedupe(values []string) []string {
+	seen := map[string]struct{}{}
+	out := []string{}
+	for _, value := range values {
+		if _, ok := seen[value]; ok {
+			continue
+		}
+		seen[value] = struct{}{}
+		out = append(out, value)
+	}
+	return out
+}
+
+func appendUnique(values []string, candidates ...string) []string {
+	seen := map[string]struct{}{}
+	for _, value := range values {
+		seen[value] = struct{}{}
+	}
+	for _, candidate := range candidates {
+		if candidate == "" {
+			continue
+		}
+		if _, ok := seen[candidate]; ok {
+			continue
+		}
+		seen[candidate] = struct{}{}
+		values = append(values, candidate)
+	}
+	return values
+}
+
+func titleWord(value string) string {
+	if value == "" {
+		return ""
+	}
+	return strings.ToUpper(value[:1]) + value[1:]
+}

internal/briefing/tomorrow_planning_module.go

@@ -0,0 +1,24 @@
+package briefing
+
+import "gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+
+type TomorrowPlanningModule struct {
+	MorningReadiness             []string `json:"morning_readiness,omitempty"`
+	CommuteSchoolWorkdayConcerns []string `json:"commute_school_workday_concerns,omitempty"`
+	OvernightChangeWatch         []string `json:"overnight_change_watch,omitempty"`
+}
+
+func buildTomorrowPlanningModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	summary := ctx.Derived.FirstDailySummary()
+	if summary == nil {
+		return &module.Output{ID: module.TomorrowPlanning, StanzaName: "tomorrow_planning", Value: TomorrowPlanningModule{}}, nil
+	}
+	planning := buildTomorrowPlanning(summary)
+	value := TomorrowPlanningModule{}
+	if planning != nil {
+		value.MorningReadiness = append([]string(nil), planning.MorningReadiness...)
+		value.CommuteSchoolWorkdayConcerns = append([]string(nil), planning.CommuteSchoolWorkdayConcerns...)
+		value.OvernightChangeWatch = append([]string(nil), planning.OvernightChangeWatch...)
+	}
+	return &module.Output{ID: module.TomorrowPlanning, StanzaName: "tomorrow_planning", Value: value}, nil
+}

internal/briefing/weather_story_module.go

@@ -0,0 +1,42 @@
+package briefing
+
+import (
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+type WeatherStoryModule struct {
+	Available   bool       `json:"available"`
+	OfficeID    string     `json:"office_id,omitempty"`
+	StartTime   time.Time  `json:"start_time"`
+	EndTime     time.Time  `json:"end_time"`
+	UpdatedAt   *time.Time `json:"updated_at,omitempty"`
+	Title       string     `json:"title,omitempty"`
+	Description string     `json:"description,omitempty"`
+	AltText     string     `json:"alt_text,omitempty"`
+	Priority    bool       `json:"priority"`
+	Order       int        `json:"order"`
+	DownloadURL string     `json:"download_url,omitempty"`
+}
+
+func buildWeatherStoryModule(ctx ModuleContext, _ any) (*module.Output, error) {
+	story := ctx.Collected.WeatherStory
+	if story == nil {
+		return nil, nil
+	}
+	value := WeatherStoryModule{
+		Available:   true,
+		OfficeID:    story.OfficeID,
+		StartTime:   story.StartTime,
+		EndTime:     story.EndTime,
+		UpdatedAt:   copyTime(story.UpdatedAt),
+		Title:       story.Title,
+		Description: story.Description,
+		AltText:     story.AltText,
+		Priority:    story.Priority,
+		Order:       story.Order,
+		DownloadURL: story.DownloadURL,
+	}
+	return &module.Output{ID: module.WeatherStory, StanzaName: "weather_story", Value: value}, nil
+}

internal/changes/daily.go

@@ -0,0 +1,312 @@
+// Package changes compares structured module snapshots.
+package changes
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+type Thresholds struct {
+	TemperatureDegrees       float64
+	PrecipProbabilityPoints  int
+	WindGustMilesPerHour     int
+	PrecipTimingShiftMinutes int
+}
+
+type Change struct {
+	Type     string `json:"type"`
+	Message  string `json:"message"`
+	Previous string `json:"previous,omitempty"`
+	Current  string `json:"current,omitempty"`
+}
+
+func CompareDaily(previous module.Snapshot, current module.Snapshot, thresholds Thresholds) ([]Change, error) {
+	previousSummary, err := requiredStanza[dailySummaryStanza](previous, "derived_daily_summary")
+	if err != nil {
+		return nil, fmt.Errorf("previous daily summary: %w", err)
+	}
+	currentSummary, err := requiredStanza[dailySummaryStanza](current, "derived_daily_summary")
+	if err != nil {
+		return nil, fmt.Errorf("current daily summary: %w", err)
+	}
+	previousDayparts, err := requiredStanza[map[string]daypartSummaryStanza](previous, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("previous daypart summaries: %w", err)
+	}
+	currentDayparts, err := requiredStanza[map[string]daypartSummaryStanza](current, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("current daypart summaries: %w", err)
+	}
+	previousAlerts, _, err := module.StanzaValue[alertDigestStanza](previous, "alert_digest")
+	if err != nil {
+		return nil, err
+	}
+	currentAlerts, _, err := module.StanzaValue[alertDigestStanza](current, "alert_digest")
+	if err != nil {
+		return nil, err
+	}
+	previousTiming, previousHasTiming, err := module.StanzaValue[precipTimingStanza](previous, "precip_timing")
+	if err != nil {
+		return nil, err
+	}
+	currentTiming, currentHasTiming, err := module.StanzaValue[precipTimingStanza](current, "precip_timing")
+	if err != nil {
+		return nil, err
+	}
+
+	var changes []Change
+	changes = append(changes, compareTemperatureValues("Low", previousSummary.LowTempF, currentSummary.LowTempF, thresholds.TemperatureDegrees)...)
+	changes = append(changes, compareTemperatureValues("High", previousSummary.HighTempF, currentSummary.HighTempF, thresholds.TemperatureDegrees)...)
+	changes = append(changes, comparePrecipitationValues(previousSummary.DailyPrecipitationProbability, currentSummary.DailyPrecipitationProbability, thresholds.PrecipProbabilityPoints, "")...)
+	if previousHasTiming && currentHasTiming {
+		changes = append(changes, comparePrecipTiming(previousTiming.MaxPopTime, currentTiming.MaxPopTime, thresholds.PrecipTimingShiftMinutes, "")...)
+	}
+	changes = append(changes, compareWindValues(previousSummary.MaxWindGustMph, currentSummary.MaxWindGustMph, thresholds.WindGustMilesPerHour, "")...)
+	changes = append(changes, compareAlerts(previousAlerts.Relevant, currentAlerts.Relevant)...)
+	changes = append(changes, compareIndicators(aggregateIndicators(previousDayparts), aggregateIndicators(currentDayparts), "")...)
+	sortChanges(changes)
+	return changes, nil
+}
+
+type dailySummaryStanza struct {
+	Date                          string `json:"date,omitempty"`
+	HighTempF                     *int   `json:"high_temp_f,omitempty"`
+	LowTempF                      *int   `json:"low_temp_f,omitempty"`
+	DailyPrecipitationProbability *int   `json:"daily_precipitation_probability,omitempty"`
+	MaxWindGustMph                *int   `json:"max_wind_gust_mph,omitempty"`
+}
+
+type daypartSummaryStanza struct {
+	Date           string `json:"date,omitempty"`
+	Period         string `json:"period,omitempty"`
+	TempRangeF     string `json:"temp_range_f,omitempty"`
+	MaxPopPercent  *int   `json:"max_pop_percent,omitempty"`
+	MaxPopTime     string `json:"max_pop_time,omitempty"`
+	MaxWindGustMph *int   `json:"max_wind_gust_mph,omitempty"`
+	Snow           bool   `json:"snow,omitempty"`
+	Ice            bool   `json:"ice,omitempty"`
+}
+
+type precipTimingStanza struct {
+	MaxPopPercent *int   `json:"max_pop_percent,omitempty"`
+	MaxPopTime    string `json:"max_pop_time,omitempty"`
+}
+
+type alertDigestStanza struct {
+	Relevant []alertSummaryStanza `json:"relevant,omitempty"`
+}
+
+type alertSummaryStanza struct {
+	Event    string `json:"event,omitempty"`
+	Headline string `json:"headline,omitempty"`
+}
+
+type indicators struct {
+	Snow bool
+	Ice  bool
+}
+
+func requiredStanza[T any](snapshot module.Snapshot, name string) (T, error) {
+	value, ok, err := module.StanzaValue[T](snapshot, name)
+	if err != nil {
+		return value, err
+	}
+	if !ok {
+		return value, fmt.Errorf("stanza %q is required", name)
+	}
+	return value, nil
+}
+
+func compareTemperatureValues(label string, previous *int, current *int, threshold float64) []Change {
+	if previous == nil || current == nil {
+		return nil
+	}
+	if !differenceAtLeast(float64(*previous), float64(*current), threshold) {
+		return nil
+	}
+	return []Change{{
+		Type:     "temperature_shift",
+		Message:  fmt.Sprintf("%s temperature changed from %d to %d.", label, *previous, *current),
+		Previous: fmt.Sprintf("%d", *previous),
+		Current:  fmt.Sprintf("%d", *current),
+	}}
+}
+
+func comparePrecipitationValues(previous *int, current *int, threshold int, prefix string) []Change {
+	if previous == nil || current == nil {
+		return nil
+	}
+	previousCategory := precipitationCategory(float64(*previous))
+	currentCategory := precipitationCategory(float64(*current))
+	if previousCategory == currentCategory && !differenceAtLeast(float64(*previous), float64(*current), float64(threshold)) {
+		return nil
+	}
+	changeType := prefix + "precip_probability_change"
+	return []Change{{
+		Type:     changeType,
+		Message:  fmt.Sprintf("Peak precipitation chance changed from %d%% (%s) to %d%% (%s).", *previous, previousCategory, *current, currentCategory),
+		Previous: fmt.Sprintf("%d%% %s", *previous, previousCategory),
+		Current:  fmt.Sprintf("%d%% %s", *current, currentCategory),
+	}}
+}
+
+func comparePrecipTiming(previous string, current string, thresholdMinutes int, prefix string) []Change {
+	if thresholdMinutes <= 0 || previous == "" || current == "" || previous == current {
+		return nil
+	}
+	previousTime, previousOK := parseClock(previous)
+	currentTime, currentOK := parseClock(current)
+	if !previousOK || !currentOK {
+		return nil
+	}
+	if int(math.Abs(currentTime.Sub(previousTime).Minutes())) < thresholdMinutes {
+		return nil
+	}
+	return []Change{{
+		Type:     prefix + "precip_timing_shift",
+		Message:  fmt.Sprintf("Peak precipitation timing shifted from %s to %s.", previous, current),
+		Previous: previous,
+		Current:  current,
+	}}
+}
+
+func compareWindValues(previous *int, current *int, threshold int, prefix string) []Change {
+	if previous == nil || current == nil || !differenceAtLeast(float64(*previous), float64(*current), float64(threshold)) {
+		return nil
+	}
+	return []Change{{
+		Type:     prefix + "wind_gust_change",
+		Message:  fmt.Sprintf("Peak wind gust changed from %d mph to %d mph.", *previous, *current),
+		Previous: fmt.Sprintf("%d mph", *previous),
+		Current:  fmt.Sprintf("%d mph", *current),
+	}}
+}
+
+func compareAlerts(previous []alertSummaryStanza, current []alertSummaryStanza) []Change {
+	previousSet := alertSet(previous)
+	currentSet := alertSet(current)
+	var changes []Change
+	for event := range currentSet {
+		if _, ok := previousSet[event]; !ok {
+			changes = append(changes, Change{Type: "alert_added", Message: fmt.Sprintf("Alert added: %s.", event), Current: event})
+		}
+	}
+	for event := range previousSet {
+		if _, ok := currentSet[event]; !ok {
+			changes = append(changes, Change{Type: "alert_removed", Message: fmt.Sprintf("Alert removed: %s.", event), Previous: event})
+		}
+	}
+	sortChanges(changes)
+	return changes
+}
+
+func compareIndicators(previous indicators, current indicators, prefix string) []Change {
+	var changes []Change
+	for _, item := range []struct {
+		name     string
+		previous bool
+		current  bool
+	}{
+		{name: "snow", previous: previous.Snow, current: current.Snow},
+		{name: "ice", previous: previous.Ice, current: current.Ice},
+	} {
+		if item.previous == item.current {
+			continue
+		}
+		changeType := prefix + item.name + "_risk_change"
+		if item.current {
+			changes = append(changes, Change{Type: changeType, Message: fmt.Sprintf("%s risk is now present.", item.name), Current: "present"})
+		} else {
+			changes = append(changes, Change{Type: changeType, Message: fmt.Sprintf("%s risk is no longer present.", item.name), Previous: "present"})
+		}
+	}
+	return changes
+}
+
+func aggregateIndicators(dayparts map[string]daypartSummaryStanza) indicators {
+	out := indicators{}
+	for _, daypart := range dayparts {
+		out.Snow = out.Snow || daypart.Snow
+		out.Ice = out.Ice || daypart.Ice
+	}
+	return out
+}
+
+func alertSet(alerts []alertSummaryStanza) map[string]struct{} {
+	out := map[string]struct{}{}
+	for _, alert := range alerts {
+		event := alert.Event
+		if event == "" {
+			event = alert.Headline
+		}
+		if event != "" {
+			out[event] = struct{}{}
+		}
+	}
+	return out
+}
+
+func precipitationCategory(value float64) string {
+	switch {
+	case value >= 70:
+		return "high"
+	case value >= 50:
+		return "likely"
+	case value >= 20:
+		return "possible"
+	default:
+		return "low"
+	}
+}
+
+func differenceAtLeast(previous float64, current float64, threshold float64) bool {
+	if threshold <= 0 {
+		return previous != current
+	}
+	return math.Abs(current-previous) >= threshold
+}
+
+func sortChanges(items []Change) {
+	sort.SliceStable(items, func(i, j int) bool {
+		if items[i].Type == items[j].Type {
+			return items[i].Message < items[j].Message
+		}
+		return items[i].Type < items[j].Type
+	})
+}
+
+func parseClock(value string) (time.Time, bool) {
+	value = strings.TrimSpace(value)
+	for _, layout := range []string{"3 PM", "3:04 PM", "15:04"} {
+		if parsed, err := time.Parse(layout, value); err == nil {
+			return parsed, true
+		}
+	}
+	return time.Time{}, false
+}
+
+func parseTempRange(value string) (*int, *int) {
+	value = strings.TrimSpace(value)
+	if value == "" {
+		return nil, nil
+	}
+	parts := strings.Split(value, "-")
+	if len(parts) == 1 {
+		if parsed, err := strconv.Atoi(strings.TrimSpace(parts[0])); err == nil {
+			return &parsed, &parsed
+		}
+		return nil, nil
+	}
+	minValue, minErr := strconv.Atoi(strings.TrimSpace(parts[0]))
+	maxValue, maxErr := strconv.Atoi(strings.TrimSpace(parts[len(parts)-1]))
+	if minErr != nil || maxErr != nil {
+		return nil, nil
+	}
+	return &minValue, &maxValue
+}

internal/changes/daily_test.go

@@ -0,0 +1,132 @@
+package changes
+
+import (
+	"strings"
+	"testing"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+func TestCompareDailyNoMeaningfulChanges(t *testing.T) {
+	previous := dailySnapshot(t, 60, 70, 30, "8 AM", nil, false)
+	current := dailySnapshot(t, 61, 71, 35, "8:30 AM", nil, false)
+
+	changes, err := CompareDaily(previous, current, testThresholds())
+	if err != nil {
+		t.Fatalf("CompareDaily() error = %v", err)
+	}
+	if len(changes) != 0 {
+		t.Fatalf("changes = %#v, want none", changes)
+	}
+}
+
+func TestCompareDailyTemperatureThreshold(t *testing.T) {
+	previous := dailySnapshot(t, 50, 70, 10, "8 AM", nil, false)
+	current := dailySnapshot(t, 58, 79, 10, "8 AM", nil, false)
+
+	changes, err := CompareDaily(previous, current, testThresholds())
+	if err != nil {
+		t.Fatalf("CompareDaily() error = %v", err)
+	}
+	if countType(changes, "temperature_shift") != 2 {
+		t.Fatalf("changes = %#v, want low and high temperature changes", changes)
+	}
+}
+
+func TestCompareDailyPrecipTimingShift(t *testing.T) {
+	previous := dailySnapshot(t, 60, 70, 60, "8 AM", nil, false)
+	current := dailySnapshot(t, 60, 70, 60, "11 AM", nil, false)
+
+	changes, err := CompareDaily(previous, current, testThresholds())
+	if err != nil {
+		t.Fatalf("CompareDaily() error = %v", err)
+	}
+	if countType(changes, "precip_timing_shift") != 1 {
+		t.Fatalf("changes = %#v, want timing shift", changes)
+	}
+}
+
+func TestCompareDailyAlertAddedAndRemoved(t *testing.T) {
+	previous := dailySnapshot(t, 60, 70, 10, "8 AM", []string{"Wind Advisory"}, false)
+	current := dailySnapshot(t, 60, 70, 10, "8 AM", []string{"Flood Watch"}, false)
+
+	changes, err := CompareDaily(previous, current, testThresholds())
+	if err != nil {
+		t.Fatalf("CompareDaily() error = %v", err)
+	}
+	if countType(changes, "alert_added") != 1 || countType(changes, "alert_removed") != 1 {
+		t.Fatalf("changes = %#v, want one alert added and one removed", changes)
+	}
+}
+
+func TestCompareDailyIndicatorChange(t *testing.T) {
+	previous := dailySnapshot(t, 60, 70, 10, "8 AM", nil, false)
+	current := dailySnapshot(t, 60, 70, 10, "8 AM", nil, true)
+
+	changes, err := CompareDaily(previous, current, testThresholds())
+	if err != nil {
+		t.Fatalf("CompareDaily() error = %v", err)
+	}
+	if countType(changes, "snow_risk_change") != 1 {
+		t.Fatalf("changes = %#v, want snow risk change", changes)
+	}
+}
+
+func TestCompareDailyRequiresComparisonStanzas(t *testing.T) {
+	_, err := CompareDaily(snapshot(t), dailySnapshot(t, 60, 70, 10, "8 AM", nil, false), testThresholds())
+	if err == nil {
+		t.Fatal("CompareDaily() error = nil, want missing stanza error")
+	}
+	if !strings.Contains(err.Error(), "derived_daily_summary") {
+		t.Fatalf("error = %q, want derived_daily_summary context", err.Error())
+	}
+}
+
+func dailySnapshot(t *testing.T, low int, high int, precip int, precipTime string, alerts []string, snow bool) module.Snapshot {
+	t.Helper()
+	relevant := make([]alertSummaryStanza, 0, len(alerts))
+	for _, alert := range alerts {
+		relevant = append(relevant, alertSummaryStanza{Event: alert})
+	}
+	return snapshot(t,
+		module.Output{ID: module.DerivedDailySummary, StanzaName: "derived_daily_summary", Value: dailySummaryStanza{
+			Date:                          "2026-05-29",
+			HighTempF:                     &high,
+			LowTempF:                      &low,
+			DailyPrecipitationProbability: &precip,
+		}},
+		module.Output{ID: module.DerivedDaypartSummaries, StanzaName: "derived_daypart_summaries", Value: map[string]daypartSummaryStanza{
+			"morning": {Date: "2026-05-29", Period: "2026-05-29 at 6:00 AM to 2026-05-29 at 10:00 AM", TempRangeF: "60-70", Snow: snow},
+		}},
+		module.Output{ID: module.PrecipTiming, StanzaName: "precip_timing", Value: precipTimingStanza{MaxPopPercent: &precip, MaxPopTime: precipTime}},
+		module.Output{ID: module.AlertDigest, StanzaName: "alert_digest", Value: alertDigestStanza{Relevant: relevant}},
+	)
+}
+
+func snapshot(t *testing.T, outputs ...module.Output) module.Snapshot {
+	t.Helper()
+	snapshot, err := module.NewSnapshot(outputs)
+	if err != nil {
+		t.Fatalf("NewSnapshot() error = %v", err)
+	}
+	return snapshot
+}
+
+func testThresholds() Thresholds {
+	return Thresholds{
+		TemperatureDegrees:       5,
+		PrecipProbabilityPoints:  20,
+		WindGustMilesPerHour:     10,
+		PrecipTimingShiftMinutes: 120,
+	}
+}
+
+func countType(changes []Change, changeType string) int {
+	var count int
+	for _, change := range changes {
+		if change.Type == changeType {
+			count++
+		}
+	}
+	return count
+}

internal/changes/three_day.go

@@ -0,0 +1,144 @@
+package changes
+
+import (
+	"fmt"
+	"sort"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+func CompareThreeDay(previous module.Snapshot, current module.Snapshot, thresholds Thresholds) ([]Change, error) {
+	previousDayparts, err := requiredStanza[map[string]daypartSummaryStanza](previous, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("previous daypart summaries: %w", err)
+	}
+	currentDayparts, err := requiredStanza[map[string]daypartSummaryStanza](current, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("current daypart summaries: %w", err)
+	}
+	previousDays := outlookDaysFromDayparts(previousDayparts)
+	currentDays := outlookDaysFromDayparts(currentDayparts)
+	return compareOutlookDays(previousDays, currentDays, thresholds, "")
+}
+
+type outlookDay struct {
+	Date           string
+	LowTempF       *int
+	HighTempF      *int
+	MaxPopPercent  *int
+	MaxPopTime     string
+	MaxWindGustMph *int
+	Indicators     indicators
+}
+
+func compareOutlookDays(previousDays map[string]outlookDay, currentDays map[string]outlookDay, thresholds Thresholds, prefix string) ([]Change, error) {
+	var changes []Change
+	for date, currentDay := range currentDays {
+		previousDay, ok := previousDays[date]
+		if !ok {
+			changes = append(changes, Change{Type: prefix + "outlook_day_added", Message: fmt.Sprintf("Outlook day added: %s.", date), Current: date})
+			continue
+		}
+		changes = append(changes, compareOutlookDay(date, previousDay, currentDay, thresholds, prefix)...)
+	}
+	for date := range previousDays {
+		if _, ok := currentDays[date]; !ok {
+			changes = append(changes, Change{Type: prefix + "outlook_day_removed", Message: fmt.Sprintf("Outlook day removed: %s.", date), Previous: date})
+		}
+	}
+	sortChanges(changes)
+	return changes, nil
+}
+
+func compareOutlookDay(date string, previous outlookDay, current outlookDay, thresholds Thresholds, prefix string) []Change {
+	var changes []Change
+	for _, change := range compareTemperatureValues("Low", previous.LowTempF, current.LowTempF, thresholds.TemperatureDegrees) {
+		change.Message = date + ": " + change.Message
+		change.Type = prefix + "outlook_" + change.Type
+		changes = append(changes, change)
+	}
+	for _, change := range compareTemperatureValues("High", previous.HighTempF, current.HighTempF, thresholds.TemperatureDegrees) {
+		change.Message = date + ": " + change.Message
+		change.Type = prefix + "outlook_" + change.Type
+		changes = append(changes, change)
+	}
+	for _, change := range comparePrecipitationValues(previous.MaxPopPercent, current.MaxPopPercent, thresholds.PrecipProbabilityPoints, prefix+"outlook_") {
+		change.Message = date + ": " + change.Message
+		changes = append(changes, change)
+	}
+	for _, change := range comparePrecipTiming(previous.MaxPopTime, current.MaxPopTime, thresholds.PrecipTimingShiftMinutes, prefix+"outlook_") {
+		change.Message = date + ": " + change.Message
+		changes = append(changes, change)
+	}
+	for _, change := range compareWindValues(previous.MaxWindGustMph, current.MaxWindGustMph, thresholds.WindGustMilesPerHour, prefix+"outlook_") {
+		change.Message = date + ": " + change.Message
+		changes = append(changes, change)
+	}
+	for _, change := range compareIndicators(previous.Indicators, current.Indicators, prefix+"outlook_") {
+		change.Message = date + ": " + change.Message
+		changes = append(changes, change)
+	}
+	return changes
+}
+
+func outlookDaysFromDayparts(dayparts map[string]daypartSummaryStanza) map[string]outlookDay {
+	out := map[string]outlookDay{}
+	var keys []string
+	for key := range dayparts {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	for _, key := range keys {
+		daypart := dayparts[key]
+		date := daypartDate(daypart)
+		if date == "" {
+			continue
+		}
+		day := out[date]
+		day.Date = date
+		low, high := parseTempRange(daypart.TempRangeF)
+		day.LowTempF = minInt(day.LowTempF, low)
+		day.HighTempF = maxInt(day.HighTempF, high)
+		day.MaxPopPercent = maxInt(day.MaxPopPercent, daypart.MaxPopPercent)
+		if daypart.MaxPopPercent != nil && day.MaxPopPercent != nil && *daypart.MaxPopPercent == *day.MaxPopPercent {
+			day.MaxPopTime = daypart.MaxPopTime
+		}
+		day.MaxWindGustMph = maxInt(day.MaxWindGustMph, daypart.MaxWindGustMph)
+		day.Indicators.Snow = day.Indicators.Snow || daypart.Snow
+		day.Indicators.Ice = day.Indicators.Ice || daypart.Ice
+		out[date] = day
+	}
+	return out
+}
+
+func daypartDate(daypart daypartSummaryStanza) string {
+	return daypart.Date
+}
+
+func minInt(a *int, b *int) *int {
+	if a == nil {
+		return copyInt(b)
+	}
+	if b != nil && *b < *a {
+		return copyInt(b)
+	}
+	return a
+}
+
+func maxInt(a *int, b *int) *int {
+	if a == nil {
+		return copyInt(b)
+	}
+	if b != nil && *b > *a {
+		return copyInt(b)
+	}
+	return a
+}
+
+func copyInt(value *int) *int {
+	if value == nil {
+		return nil
+	}
+	copied := *value
+	return &copied
+}

internal/changes/three_day_test.go

@@ -0,0 +1,42 @@
+package changes
+
+import (
+	"testing"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+func TestCompareThreeDayDetectsDayChanges(t *testing.T) {
+	previous := outlookSnapshot(t, "2026-05-29", "70", 20, "9 AM", false)
+	current := outlookSnapshot(t, "2026-05-29", "78", 70, "12 PM", true)
+
+	changes, err := CompareThreeDay(previous, current, Thresholds{
+		TemperatureDegrees:       5,
+		PrecipProbabilityPoints:  20,
+		PrecipTimingShiftMinutes: 120,
+	})
+	if err != nil {
+		t.Fatalf("CompareThreeDay() error = %v", err)
+	}
+
+	if len(changes) == 0 {
+		t.Fatal("changes length = 0, want detected 3-day changes")
+	}
+	if countType(changes, "outlook_precip_probability_change") == 0 || countType(changes, "outlook_snow_risk_change") == 0 {
+		t.Fatalf("changes = %#v, want precipitation and snow changes", changes)
+	}
+}
+
+func outlookSnapshot(t *testing.T, date string, tempRange string, precip int, precipTime string, snow bool) module.Snapshot {
+	t.Helper()
+	return snapshot(t, module.Output{ID: module.DerivedDaypartSummaries, StanzaName: "derived_daypart_summaries", Value: map[string]daypartSummaryStanza{
+		date + "_morning": {
+			Date:          date,
+			Period:        date + " at 6:00 AM to " + date + " at 10:00 AM",
+			TempRangeF:    tempRange,
+			MaxPopPercent: &precip,
+			MaxPopTime:    precipTime,
+			Snow:          snow,
+		},
+	}})
+}

internal/changes/weekend.go

@@ -0,0 +1,19 @@
+package changes
+
+import (
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+)
+
+func CompareWeekend(previous module.Snapshot, current module.Snapshot, thresholds Thresholds) ([]Change, error) {
+	previousDayparts, err := requiredStanza[map[string]daypartSummaryStanza](previous, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("previous weekend daypart summaries: %w", err)
+	}
+	currentDayparts, err := requiredStanza[map[string]daypartSummaryStanza](current, "derived_daypart_summaries")
+	if err != nil {
+		return nil, fmt.Errorf("current weekend daypart summaries: %w", err)
+	}
+	return compareOutlookDays(outlookDaysFromDayparts(previousDayparts), outlookDaysFromDayparts(currentDayparts), thresholds, "weekend_")
+}

internal/changes/weekend_test.go

@@ -0,0 +1,19 @@
+package changes
+
+import "testing"
+
+func TestCompareWeekendDetectsOutlookChanges(t *testing.T) {
+	previous := outlookSnapshot(t, "2026-05-30", "70", 10, "9 AM", false)
+	current := outlookSnapshot(t, "2026-05-30", "78", 10, "9 AM", true)
+
+	changes, err := CompareWeekend(previous, current, Thresholds{TemperatureDegrees: 5})
+	if err != nil {
+		t.Fatalf("CompareWeekend() error = %v", err)
+	}
+	if len(changes) == 0 {
+		t.Fatal("changes length = 0, want weekend changes")
+	}
+	if countType(changes, "weekend_outlook_snow_risk_change") == 0 {
+		t.Fatalf("changes = %#v, want snow risk change", changes)
+	}
+}

internal/cli/root.go

@@ -0,0 +1,409 @@
+package cli
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/app"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/config"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+const helpText = `weatherreporter prepares weather reports from normalized forecast data.
+
+Usage:
+  weatherreporter --help
+  weatherreporter generate daily [--config PATH] [--units VALUE] [--tz NAME] [--out PATH] [--date YYYY-MM-DD]
+  weatherreporter generate tomorrow [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+  weatherreporter generate three-day [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+  weatherreporter generate weekend [--config PATH] [--units VALUE] [--tz NAME] [--out PATH]
+  weatherreporter generate storm [--config PATH] [--units VALUE] [--tz NAME] [--out PATH] --start TIME --end TIME
+  weatherreporter run morning [--config PATH] [--units VALUE] [--tz NAME] [--out-dir PATH]
+  weatherreporter run evening [--config PATH] [--units VALUE] [--tz NAME] [--out-dir PATH]
+  weatherreporter inspect reports [--config PATH] [--limit N]
+  weatherreporter inspect metadata [--config PATH] RUN_ID
+  weatherreporter inspect modules [--config PATH] RUN_ID
+  weatherreporter inspect data-package [--config PATH] RUN_ID
+  weatherreporter inspect prior [--config PATH] RUN_ID
+  weatherreporter inspect sources [--config PATH] RUN_ID
+
+Options:
+  -h, --help       Show this help message.
+  --config PATH    Load configuration from PATH instead of /usr/local/etc/weatherreporter/config.yml.
+  --units VALUE    Override weather API units.
+  --tz NAME        Override weather API timezone.
+  --out PATH       Write an extra Markdown report copy for generate commands.
+  --out-dir PATH   Write extra Markdown report copies for run commands.
+`
+
+type Runner struct {
+	Clock timeutil.Clock
+}
+
+func Run(ctx context.Context, args []string, stdout io.Writer, stderr io.Writer) error {
+	return Runner{Clock: timeutil.SystemClock{}}.Run(ctx, args, stdout, stderr)
+}
+
+func (r Runner) Run(ctx context.Context, args []string, stdout io.Writer, stderr io.Writer) error {
+	_ = stderr
+	if r.Clock == nil {
+		r.Clock = timeutil.SystemClock{}
+	}
+	if len(args) == 0 || args[0] == "--help" || args[0] == "-h" {
+		_, err := fmt.Fprint(stdout, helpText)
+		return err
+	}
+
+	switch args[0] {
+	case "generate":
+		req, err := r.resolveGenerate(args[1:])
+		if err != nil {
+			return err
+		}
+		return app.Generate(ctx, req)
+	case "run":
+		req, err := r.resolveRun(args[1:])
+		if err != nil {
+			return err
+		}
+		result, err := app.RunBatchDetailed(ctx, req)
+		if result != nil {
+			writeRunLogs(stderr, result)
+			if encodeErr := writeJSON(stdout, result); encodeErr != nil {
+				return encodeErr
+			}
+			if result.Failed > 0 {
+				return app.BatchError{Result: result}
+			}
+		}
+		return err
+	case "inspect":
+		return r.runInspect(ctx, args[1:], stdout)
+	default:
+		return fmt.Errorf("unknown command %q", args[0])
+	}
+}
+
+type commonOptions struct {
+	ConfigPath string
+	Units      string
+	Timezone   string
+	Output     string
+	OutputDir  string
+}
+
+type generateOptions struct {
+	commonOptions
+	Date  string
+	Start string
+	End   string
+}
+
+type inspectOptions struct {
+	ConfigPath string
+	Limit      int
+	RunID      string
+}
+
+type inspectRunCommand struct {
+	Name    string
+	Inspect func(context.Context, app.InspectRunRequest) (any, error)
+}
+
+var inspectRunCommands = []inspectRunCommand{
+	{Name: "metadata", Inspect: func(ctx context.Context, req app.InspectRunRequest) (any, error) {
+		return app.InspectMetadata(ctx, req)
+	}},
+	{Name: "modules", Inspect: func(ctx context.Context, req app.InspectRunRequest) (any, error) {
+		return app.InspectModules(ctx, req)
+	}},
+	{Name: "data-package", Inspect: func(ctx context.Context, req app.InspectRunRequest) (any, error) {
+		return app.InspectDataPackage(ctx, req)
+	}},
+	{Name: "prior", Inspect: func(ctx context.Context, req app.InspectRunRequest) (any, error) {
+		return app.InspectPriorSnapshot(ctx, req)
+	}},
+	{Name: "sources", Inspect: func(ctx context.Context, req app.InspectRunRequest) (any, error) {
+		return app.InspectSources(ctx, req)
+	}},
+}
+
+func (r Runner) runInspect(ctx context.Context, args []string, stdout io.Writer) error {
+	if len(args) == 0 {
+		return fmt.Errorf("inspect requires a command")
+	}
+	command := args[0]
+	switch command {
+	case "reports":
+		opts, err := parseInspectReportsFlags(args[1:])
+		if err != nil {
+			return err
+		}
+		cfg, err := config.Load(config.LoadOptions{Path: opts.ConfigPath})
+		if err != nil {
+			return err
+		}
+		records, err := app.InspectReports(ctx, app.InspectReportsRequest{Config: cfg, Limit: opts.Limit})
+		if err != nil {
+			return err
+		}
+		return writeJSON(stdout, records)
+	default:
+		for _, candidate := range inspectRunCommands {
+			if candidate.Name == command {
+				return runInspectRunCommand(ctx, stdout, candidate, args[1:])
+			}
+		}
+		return fmt.Errorf("unknown inspect command %q", command)
+	}
+}
+
+func runInspectRunCommand(ctx context.Context, stdout io.Writer, command inspectRunCommand, args []string) error {
+	opts, err := parseInspectRunFlags(command.Name, args)
+	if err != nil {
+		return err
+	}
+	cfg, err := config.Load(config.LoadOptions{Path: opts.ConfigPath})
+	if err != nil {
+		return err
+	}
+	value, err := command.Inspect(ctx, app.InspectRunRequest{Config: cfg, RunID: opts.RunID})
+	if err != nil {
+		return err
+	}
+	return writeJSON(stdout, value)
+}
+
+func (r Runner) resolveGenerate(args []string) (app.GenerateRequest, error) {
+	if r.Clock == nil {
+		r.Clock = timeutil.SystemClock{}
+	}
+	if len(args) == 0 {
+		return app.GenerateRequest{}, fmt.Errorf("generate requires a report name")
+	}
+	reportKind, ok := reportKind(args[0])
+	if !ok {
+		return app.GenerateRequest{}, fmt.Errorf("unknown generate report %q", args[0])
+	}
+
+	opts, err := parseGenerateFlags(reportKind, args[1:])
+	if err != nil {
+		return app.GenerateRequest{}, err
+	}
+	cfg, err := config.Load(config.LoadOptions{
+		Path:     opts.ConfigPath,
+		Units:    opts.Units,
+		Timezone: opts.Timezone,
+	})
+	if err != nil {
+		return app.GenerateRequest{}, err
+	}
+	location, err := timeutil.LoadLocation(cfg.WeatherAPI.Timezone)
+	if err != nil {
+		return app.GenerateRequest{}, err
+	}
+
+	req := app.GenerateRequest{
+		Config:     cfg,
+		Report:     reportKind,
+		OutputPath: opts.Output,
+		Now:        r.Clock.Now(),
+	}
+
+	switch reportKind {
+	case app.ReportDaily:
+		if opts.Date == "" {
+			req.Date = timeutil.LocalDate(r.Clock.Now(), location)
+		} else {
+			req.Date, err = timeutil.ParseLocalDate(opts.Date, location)
+			if err != nil {
+				return app.GenerateRequest{}, err
+			}
+		}
+	case app.ReportStorm:
+		if opts.Start == "" {
+			return app.GenerateRequest{}, fmt.Errorf("generate storm requires --start")
+		}
+		if opts.End == "" {
+			return app.GenerateRequest{}, fmt.Errorf("generate storm requires --end")
+		}
+		period, err := report.ParseStormPeriod(opts.Start, opts.End, location)
+		if err != nil {
+			return app.GenerateRequest{}, err
+		}
+		req.StormStart = period.Start
+		req.StormEnd = period.End
+	}
+
+	return req, nil
+}
+
+func (r Runner) resolveRun(args []string) (app.BatchRequest, error) {
+	if r.Clock == nil {
+		r.Clock = timeutil.SystemClock{}
+	}
+	if len(args) == 0 {
+		return app.BatchRequest{}, fmt.Errorf("run requires a batch name")
+	}
+	batch, ok := batchKind(args[0])
+	if !ok {
+		return app.BatchRequest{}, fmt.Errorf("unknown run batch %q", args[0])
+	}
+	opts, err := parseRunFlags(args[1:])
+	if err != nil {
+		return app.BatchRequest{}, err
+	}
+	cfg, err := config.Load(config.LoadOptions{
+		Path:     opts.ConfigPath,
+		Units:    opts.Units,
+		Timezone: opts.Timezone,
+	})
+	if err != nil {
+		return app.BatchRequest{}, err
+	}
+	return app.BatchRequest{Config: cfg, Batch: batch, Now: r.Clock.Now(), OutputDir: opts.OutputDir}, nil
+}
+
+func resolveRun(args []string) (app.BatchRequest, error) {
+	return Runner{Clock: timeutil.SystemClock{}}.resolveRun(args)
+}
+
+func parseGenerateFlags(report app.ReportKind, args []string) (generateOptions, error) {
+	fs := flag.NewFlagSet("generate "+string(report), flag.ContinueOnError)
+	fs.SetOutput(io.Discard)
+	opts := generateOptions{}
+	addCommonFlags(fs, &opts.commonOptions, true)
+	if report == app.ReportDaily {
+		fs.StringVar(&opts.Date, "date", "", "report date in YYYY-MM-DD")
+	}
+	if report == app.ReportStorm {
+		fs.StringVar(&opts.Start, "start", "", "storm start time")
+		fs.StringVar(&opts.End, "end", "", "storm end time")
+	}
+	if err := fs.Parse(args); err != nil {
+		return generateOptions{}, err
+	}
+	if fs.NArg() > 0 {
+		return generateOptions{}, fmt.Errorf("unexpected argument %q", fs.Arg(0))
+	}
+	return opts, nil
+}
+
+func parseRunFlags(args []string) (commonOptions, error) {
+	fs := flag.NewFlagSet("run", flag.ContinueOnError)
+	fs.SetOutput(io.Discard)
+	opts := commonOptions{}
+	addCommonFlags(fs, &opts, false)
+	fs.StringVar(&opts.OutputDir, "out-dir", "", "extra Markdown report copy directory")
+	if err := fs.Parse(args); err != nil {
+		return commonOptions{}, err
+	}
+	if fs.NArg() > 0 {
+		return commonOptions{}, fmt.Errorf("unexpected argument %q", fs.Arg(0))
+	}
+	return opts, nil
+}
+
+func parseInspectReportsFlags(args []string) (inspectOptions, error) {
+	fs := flag.NewFlagSet("inspect reports", flag.ContinueOnError)
+	fs.SetOutput(io.Discard)
+	opts := inspectOptions{Limit: 20}
+	fs.StringVar(&opts.ConfigPath, "config", "", "configuration file path")
+	fs.IntVar(&opts.Limit, "limit", 20, "maximum reports to list")
+	if err := fs.Parse(args); err != nil {
+		return inspectOptions{}, err
+	}
+	if fs.NArg() > 0 {
+		return inspectOptions{}, fmt.Errorf("unexpected argument %q", fs.Arg(0))
+	}
+	if opts.Limit < 0 {
+		return inspectOptions{}, fmt.Errorf("limit must be zero or greater")
+	}
+	return opts, nil
+}
+
+func parseInspectRunFlags(command string, args []string) (inspectOptions, error) {
+	fs := flag.NewFlagSet("inspect "+command, flag.ContinueOnError)
+	fs.SetOutput(io.Discard)
+	opts := inspectOptions{}
+	fs.StringVar(&opts.ConfigPath, "config", "", "configuration file path")
+	if err := fs.Parse(args); err != nil {
+		return inspectOptions{}, err
+	}
+	if fs.NArg() != 1 {
+		return inspectOptions{}, fmt.Errorf("inspect %s requires a run id", command)
+	}
+	opts.RunID = fs.Arg(0)
+	return opts, nil
+}
+
+func writeJSON(stdout io.Writer, value any) error {
+	encoder := json.NewEncoder(stdout)
+	encoder.SetIndent("", "  ")
+	return encoder.Encode(value)
+}
+
+func writeRunLogs(stderr io.Writer, result *app.BatchResult) {
+	if stderr == nil || result == nil {
+		return
+	}
+	for _, item := range result.Reports {
+		notificationFields := ""
+		if item.NotificationStatus != "" {
+			notificationFields += fmt.Sprintf(" notificationStatus=%q", item.NotificationStatus)
+		}
+		if item.NotificationRunID != "" {
+			notificationFields += fmt.Sprintf(" notificationRunId=%q", item.NotificationRunID)
+		}
+		if item.NotificationError != "" {
+			notificationFields += fmt.Sprintf(" notificationError=%q", item.NotificationError)
+		}
+		if item.Status == "failed" {
+			_, _ = fmt.Fprintf(stderr, "report=%s status=failed error=%q%s\n", item.ReportID, item.Error, notificationFields)
+			continue
+		}
+		_, _ = fmt.Fprintf(stderr, "report=%s status=succeeded output=%q%s\n", item.ReportID, item.OutputPath, notificationFields)
+	}
+	_, _ = fmt.Fprintf(stderr, "batch=%s total=%d succeeded=%d failed=%d\n", result.Batch, result.Total, result.Succeeded, result.Failed)
+}
+
+func addCommonFlags(fs *flag.FlagSet, opts *commonOptions, includeOutput bool) {
+	fs.StringVar(&opts.ConfigPath, "config", "", "configuration file path")
+	fs.StringVar(&opts.Units, "units", "", "weather API units")
+	fs.StringVar(&opts.Timezone, "tz", "", "weather API timezone")
+	if includeOutput {
+		fs.StringVar(&opts.Output, "out", "", "extra Markdown report copy path")
+	}
+}
+
+func reportKind(value string) (app.ReportKind, bool) {
+	switch value {
+	case string(app.ReportDaily):
+		return app.ReportDaily, true
+	case string(app.ReportTomorrow):
+		return app.ReportTomorrow, true
+	case string(app.ReportThreeDay):
+		return app.ReportThreeDay, true
+	case string(app.ReportWeekend):
+		return app.ReportWeekend, true
+	case string(app.ReportStorm):
+		return app.ReportStorm, true
+	default:
+		return "", false
+	}
+}
+
+func batchKind(value string) (app.BatchKind, bool) {
+	switch value {
+	case string(app.BatchMorning):
+		return app.BatchMorning, true
+	case string(app.BatchEvening):
+		return app.BatchEvening, true
+	default:
+		return "", false
+	}
+}

internal/config/config.go

@@ -0,0 +1,173 @@
+// Package config owns application configuration structures, defaults, loading,
+// precedence, and validation.
+package config
+
+import (
+	"fmt"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gopkg.in/yaml.v3"
+)
+
+type MissingSourcePolicy string
+type NotifyFailurePolicy string
+
+const (
+	MissingSourceError MissingSourcePolicy = "error"
+	MissingSourceWarn  MissingSourcePolicy = "warn"
+	MissingSourceNone  MissingSourcePolicy = "none"
+
+	NotifyFailureError NotifyFailurePolicy = "error"
+)
+
+type Config struct {
+	WeatherAPI    WeatherAPIConfig        `yaml:"weather_api"`
+	Location      LocationConfig          `yaml:"location"`
+	Secrets       SecretsConfig           `yaml:"secrets"`
+	Notify        NotifyConfig            `yaml:"notify"`
+	MissingSource MissingSourceConfig     `yaml:"missing_source"`
+	Scriptorium   ScriptoriumConfig       `yaml:"scriptorium"`
+	Workspace     WorkspaceConfig         `yaml:"workspace"`
+	Dayparts      []DaypartConfig         `yaml:"dayparts"`
+	RecentChange  RecentChangeConfig      `yaml:"recent_change"`
+	Reports       map[string]ReportConfig `yaml:"reports"`
+}
+
+type WeatherAPIConfig struct {
+	BaseURL   string        `yaml:"base_url"`
+	Timeout   time.Duration `yaml:"timeout"`
+	Precision int           `yaml:"precision"`
+	Units     string        `yaml:"units"`
+	Timezone  string        `yaml:"timezone"`
+	Format    string        `yaml:"format"`
+}
+
+type LocationConfig struct {
+	ID     string `yaml:"id"`
+	Name   string `yaml:"name"`
+	Region string `yaml:"region"`
+}
+
+type SecretsConfig struct {
+	Directory string `yaml:"directory"`
+}
+
+type NotifyConfig struct {
+	Distributor DistributorNotifyConfig `yaml:"distributor"`
+}
+
+type DistributorNotifyConfig struct {
+	Enabled                bool                `yaml:"enabled"`
+	Endpoint               string              `yaml:"endpoint"`
+	TokenEnv               string              `yaml:"token_env"`
+	Timeout                time.Duration       `yaml:"timeout"`
+	FailurePolicy          NotifyFailurePolicy `yaml:"failure_policy"`
+	PipelineIDTemplate     string              `yaml:"pipeline_id_template"`
+	BundleIDTemplate       string              `yaml:"bundle_id_template"`
+	IdempotencyKeyTemplate string              `yaml:"idempotency_key_template"`
+	ReportPathTemplates    []string            `yaml:"report_path_templates"`
+}
+
+type MissingSourceConfig struct {
+	Default MissingSourcePolicy            `yaml:"default"`
+	Sources map[string]MissingSourcePolicy `yaml:"sources"`
+}
+
+type ScriptoriumConfig struct {
+	Binary     string        `yaml:"binary"`
+	ConfigPath string        `yaml:"config_path"`
+	Profile    string        `yaml:"profile"`
+	Timeout    time.Duration `yaml:"timeout"`
+	ExtraArgs  []string      `yaml:"extra_args"`
+}
+
+type WorkspaceConfig struct {
+	Root             string `yaml:"root"`
+	SnapshotsDir     string `yaml:"snapshots_dir"`
+	ReportsDir       string `yaml:"reports_dir"`
+	DataPackagesDir  string `yaml:"data_packages_dir"`
+	PreflightDir     string `yaml:"preflight_dir"`
+	NotificationsDir string `yaml:"notifications_dir"`
+}
+
+type DaypartConfig struct {
+	Name  string `yaml:"name"`
+	Start string `yaml:"start"`
+	End   string `yaml:"end"`
+}
+
+type RecentChangeConfig struct {
+	TemperatureDegrees       float64 `yaml:"temperature_degrees"`
+	PrecipProbabilityPoints  int     `yaml:"precip_probability_points"`
+	WindGustMilesPerHour     int     `yaml:"wind_gust_miles_per_hour"`
+	PrecipTimingShiftMinutes int     `yaml:"precip_timing_shift_minutes"`
+}
+
+type ReportConfig struct {
+	DeterministicModules    []ModuleConfigItem `yaml:"deterministic_modules"`
+	deterministicModulesSet bool
+}
+
+type ModuleConfigItem struct {
+	ID      module.ID `yaml:"id"`
+	Options any       `yaml:"options,omitempty"`
+}
+
+func (c *ReportConfig) UnmarshalYAML(value *yaml.Node) error {
+	if value.Kind != yaml.MappingNode {
+		return fmt.Errorf("report entry must be a mapping")
+	}
+	for i := 0; i < len(value.Content); i += 2 {
+		key := value.Content[i].Value
+		node := value.Content[i+1]
+		switch key {
+		case "deterministic_modules":
+			if err := node.Decode(&c.DeterministicModules); err != nil {
+				return err
+			}
+			c.deterministicModulesSet = true
+		default:
+			return fmt.Errorf("unknown report entry field %q", key)
+		}
+	}
+	return nil
+}
+
+func (m *ModuleConfigItem) UnmarshalYAML(value *yaml.Node) error {
+	switch value.Kind {
+	case yaml.ScalarNode:
+		if value.Value == "" {
+			return fmt.Errorf("module id is required")
+		}
+		m.ID = module.ID(value.Value)
+		return nil
+	case yaml.MappingNode:
+		var sawID bool
+		for i := 0; i < len(value.Content); i += 2 {
+			key := value.Content[i].Value
+			node := value.Content[i+1]
+			switch key {
+			case "id":
+				if err := node.Decode(&m.ID); err != nil {
+					return err
+				}
+				sawID = true
+			case "options":
+				var options any
+				if err := node.Decode(&options); err != nil {
+					return err
+				}
+				m.Options = options
+			default:
+				return fmt.Errorf("unknown module entry field %q", key)
+			}
+		}
+		if !sawID || m.ID == "" {
+			return fmt.Errorf("module id is required")
+		}
+		return nil
+	default:
+		return fmt.Errorf("module entry must be a string or mapping")
+	}
+}

internal/config/config_test.go

@@ -0,0 +1,782 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+)
+
+func TestDefaults(t *testing.T) {
+	cfg, err := Load(LoadOptions{})
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+
+	if cfg.WeatherAPI.Units != "us" {
+		t.Fatalf("Units = %q, want us", cfg.WeatherAPI.Units)
+	}
+	if cfg.WeatherAPI.Timezone != "America/Chicago" {
+		t.Fatalf("Timezone = %q, want America/Chicago", cfg.WeatherAPI.Timezone)
+	}
+	if cfg.WeatherAPI.Format != "json" {
+		t.Fatalf("Format = %q, want json", cfg.WeatherAPI.Format)
+	}
+	if cfg.Location.ID != "home" || cfg.Location.Name != "Brentwood" || cfg.Location.Region != "St. Louis Metro" {
+		t.Fatalf("Location = %#v, want home/Brentwood/St. Louis Metro", cfg.Location)
+	}
+	if cfg.Secrets.Directory != "" {
+		t.Fatalf("Secrets.Directory = %q, want empty", cfg.Secrets.Directory)
+	}
+	if cfg.Notify.Distributor.Enabled {
+		t.Fatalf("Notify.Distributor.Enabled = true, want false")
+	}
+	if cfg.Notify.Distributor.Endpoint != "https://distributor.example.com" {
+		t.Fatalf("Notify.Distributor.Endpoint = %q, want default endpoint", cfg.Notify.Distributor.Endpoint)
+	}
+	if cfg.Notify.Distributor.TokenEnv != "DISTRIBUTOR_UPLOAD_TOKEN" {
+		t.Fatalf("Notify.Distributor.TokenEnv = %q, want DISTRIBUTOR_UPLOAD_TOKEN", cfg.Notify.Distributor.TokenEnv)
+	}
+	if cfg.Notify.Distributor.Timeout != 30*time.Second {
+		t.Fatalf("Notify.Distributor.Timeout = %s, want 30s", cfg.Notify.Distributor.Timeout)
+	}
+	if cfg.Notify.Distributor.FailurePolicy != NotifyFailureError {
+		t.Fatalf("Notify.Distributor.FailurePolicy = %q, want error", cfg.Notify.Distributor.FailurePolicy)
+	}
+	if cfg.Notify.Distributor.PipelineIDTemplate != "" {
+		t.Fatalf("Notify.Distributor.PipelineIDTemplate = %q, want empty", cfg.Notify.Distributor.PipelineIDTemplate)
+	}
+	if cfg.Notify.Distributor.BundleIDTemplate != "weatherreporter.{location_id}.{report_id}" {
+		t.Fatalf("Notify.Distributor.BundleIDTemplate = %q, want default", cfg.Notify.Distributor.BundleIDTemplate)
+	}
+	if cfg.Notify.Distributor.IdempotencyKeyTemplate != "{bundle_id}.{run_id}" {
+		t.Fatalf("Notify.Distributor.IdempotencyKeyTemplate = %q, want default", cfg.Notify.Distributor.IdempotencyKeyTemplate)
+	}
+	wantReportPaths := []string{
+		"{valid_start_date}/{artifact_group}/{valid_start_date}-{artifact_group}-{run_id}.md",
+	}
+	if strings.Join(cfg.Notify.Distributor.ReportPathTemplates, "\n") != strings.Join(wantReportPaths, "\n") {
+		t.Fatalf("Notify.Distributor.ReportPathTemplates = %#v, want %#v", cfg.Notify.Distributor.ReportPathTemplates, wantReportPaths)
+	}
+	if cfg.MissingSource.Default != MissingSourceWarn {
+		t.Fatalf("MissingSource.Default = %q, want warn", cfg.MissingSource.Default)
+	}
+}
+
+func TestLoadExampleConfig(t *testing.T) {
+	cfg, err := LoadFile(filepath.Join("..", "..", "examples", "config.yml"))
+	if err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+
+	if cfg.WeatherAPI.BaseURL != "https://weather.api.rakestrawhome.com/" {
+		t.Fatalf("BaseURL = %q, want configured example URL", cfg.WeatherAPI.BaseURL)
+	}
+	if cfg.WeatherAPI.Timeout != 15*time.Second {
+		t.Fatalf("Timeout = %s, want 15s", cfg.WeatherAPI.Timeout)
+	}
+	if cfg.MissingSource.Sources["alerts"] != MissingSourceNone {
+		t.Fatalf("alerts policy = %q, want none", cfg.MissingSource.Sources["alerts"])
+	}
+	if cfg.Location.ID != "home" || cfg.Location.Name != "Brentwood" || cfg.Location.Region != "St. Louis Metro" {
+		t.Fatalf("Location = %#v, want example location", cfg.Location)
+	}
+	if cfg.Notify.Distributor.PipelineIDTemplate != "weatherreporter.{artifact_group}" {
+		t.Fatalf("PipelineIDTemplate = %q, want example pipeline template", cfg.Notify.Distributor.PipelineIDTemplate)
+	}
+	if len(cfg.Notify.Distributor.ReportPathTemplates) != 1 {
+		t.Fatalf("ReportPathTemplates = %#v, want example archive path", cfg.Notify.Distributor.ReportPathTemplates)
+	}
+}
+
+func TestLoadMinimalExampleConfig(t *testing.T) {
+	cfg, err := LoadFile(filepath.Join("..", "..", "examples", "minimal-config.yml"))
+	if err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+
+	if cfg.WeatherAPI.BaseURL != "https://weather.api.example.com/" {
+		t.Fatalf("BaseURL = %q, want example URL", cfg.WeatherAPI.BaseURL)
+	}
+	if cfg.WeatherAPI.Units != "us" {
+		t.Fatalf("Units = %q, want default us", cfg.WeatherAPI.Units)
+	}
+	if cfg.Scriptorium.Binary != "scriptorium" {
+		t.Fatalf("Scriptorium.Binary = %q, want default scriptorium", cfg.Scriptorium.Binary)
+	}
+	if cfg.Workspace.Root != "workspace" {
+		t.Fatalf("Workspace.Root = %q, want default workspace", cfg.Workspace.Root)
+	}
+	if cfg.Workspace.NotificationsDir != "notifications" {
+		t.Fatalf("Workspace.NotificationsDir = %q, want notifications", cfg.Workspace.NotificationsDir)
+	}
+	if cfg.Location.Name != "Brentwood" {
+		t.Fatalf("Location.Name = %q, want default Brentwood", cfg.Location.Name)
+	}
+}
+
+func TestLoadReportModuleOverrides(t *testing.T) {
+	path := writeConfig(t, `
+reports:
+  daily:
+    deterministic_modules:
+      - metadata
+      - current_conditions
+      - id: area_forecast_discussion
+        options:
+          sections:
+            - short_term
+`)
+
+	cfg, err := LoadFile(path)
+	if err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+	overrides := cfg.ReportModuleOverrides()
+	items := overrides[report.DailyToday]
+	if len(items) != 3 {
+		t.Fatalf("daily override length = %d, want 3", len(items))
+	}
+	if items[0].ID != module.Metadata || items[1].ID != module.CurrentConditions || items[2].ID != module.AreaForecastDiscussion {
+		t.Fatalf("daily override = %#v, want configured module order", items)
+	}
+	options, ok := items[2].Options.(module.AreaForecastDiscussionOptions)
+	if !ok {
+		t.Fatalf("AFD options type = %T, want AreaForecastDiscussionOptions", items[2].Options)
+	}
+	if strings.Join(options.Sections, ",") != "short_term" {
+		t.Fatalf("AFD sections = %#v, want short_term", options.Sections)
+	}
+}
+
+func TestReportModuleOverrideValidation(t *testing.T) {
+	tests := []struct {
+		name    string
+		yaml    string
+		wantErr string
+	}{
+		{
+			name: "UnknownReport",
+			yaml: `
+reports:
+  moon:
+    deterministic_modules:
+      - metadata
+`,
+			wantErr: "reports.moon",
+		},
+		{
+			name: "UnknownModule",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - missing_module
+`,
+			wantErr: `unknown module "missing_module"`,
+		},
+		{
+			name: "DuplicateModule",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - metadata
+      - metadata
+`,
+			wantErr: `duplicate module "metadata"`,
+		},
+		{
+			name: "IncompatibleModule",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - tomorrow_planning
+`,
+			wantErr: `not compatible with report "daily_today"`,
+		},
+		{
+			name: "RemovedPlaceholderModule",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - forecast_delta
+`,
+			wantErr: `unknown module "forecast_delta"`,
+		},
+		{
+			name: "InvalidOptions",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - id: metadata
+        options:
+          sections:
+            - short_term
+`,
+			wantErr: "options are invalid",
+		},
+		{
+			name: "DuplicateReportAlias",
+			yaml: `
+reports:
+  daily:
+    deterministic_modules:
+      - metadata
+  daily_today:
+    deterministic_modules:
+      - current_conditions
+`,
+			wantErr: "duplicates report override",
+		},
+		{
+			name: "UnknownReportField",
+			yaml: `
+reports:
+  daily:
+    modules:
+      - metadata
+`,
+			wantErr: `unknown report entry field "modules"`,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := LoadFile(writeConfig(t, tt.yaml))
+			if err == nil {
+				t.Fatal("LoadFile() error = nil, want validation error")
+			}
+			if !strings.Contains(err.Error(), tt.wantErr) {
+				t.Fatalf("error = %q, want %q", err.Error(), tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestExplicitMissingConfigReturnsError(t *testing.T) {
+	_, err := LoadFile(filepath.Join(t.TempDir(), "missing.yml"))
+	if err == nil {
+		t.Fatal("LoadFile() error = nil, want missing file error")
+	}
+	if !strings.Contains(err.Error(), "read config") {
+		t.Fatalf("error = %q, want read config context", err.Error())
+	}
+}
+
+func writeConfig(t *testing.T, contents string) string {
+	t.Helper()
+	path := filepath.Join(t.TempDir(), "config.yml")
+	if err := os.WriteFile(path, []byte(contents), 0o600); err != nil {
+		t.Fatalf("write config fixture: %v", err)
+	}
+	return path
+}
+
+func TestInvalidConfigProducesActionableError(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.yml")
+	if err := os.WriteFile(path, []byte("missing_source:\n  default: explode\n"), 0o600); err != nil {
+		t.Fatalf("write config fixture: %v", err)
+	}
+
+	_, err := LoadFile(path)
+	if err == nil {
+		t.Fatal("LoadFile() error = nil, want validation error")
+	}
+	if !strings.Contains(err.Error(), "missing_source.default") {
+		t.Fatalf("error = %q, want field path", err.Error())
+	}
+}
+
+func TestLoadAppliesOverrides(t *testing.T) {
+	cfg, err := Load(LoadOptions{Units: "metric", Timezone: "+09:30"})
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+	if cfg.WeatherAPI.Units != "metric" {
+		t.Fatalf("Units = %q, want metric", cfg.WeatherAPI.Units)
+	}
+	if cfg.WeatherAPI.Timezone != "+09:30" {
+		t.Fatalf("Timezone = %q, want +09:30", cfg.WeatherAPI.Timezone)
+	}
+}
+
+func TestDisabledDistributorNotifyAcceptsOmittedFields(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.yml")
+	if err := os.WriteFile(path, []byte("notify:\n  distributor:\n    enabled: false\n"), 0o600); err != nil {
+		t.Fatalf("write config fixture: %v", err)
+	}
+
+	cfg, err := LoadFile(path)
+	if err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+	if cfg.Notify.Distributor.Enabled {
+		t.Fatalf("Notify.Distributor.Enabled = true, want false")
+	}
+}
+
+func TestEnabledDistributorNotifyValidation(t *testing.T) {
+	tests := []struct {
+		name    string
+		mutate  func(*Config)
+		wantErr string
+	}{
+		{
+			name: "Endpoint",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.Endpoint = "distributor.example.com"
+			},
+			wantErr: "notify.distributor.endpoint",
+		},
+		{
+			name: "TokenEnvEmpty",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.TokenEnv = ""
+			},
+			wantErr: "notify.distributor.token_env",
+		},
+		{
+			name: "TokenEnvInvalid",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.TokenEnv = "1TOKEN"
+			},
+			wantErr: "notify.distributor.token_env",
+		},
+		{
+			name: "Timeout",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.Timeout = 0
+			},
+			wantErr: "notify.distributor.timeout",
+		},
+		{
+			name: "FailurePolicy",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.FailurePolicy = "warn"
+			},
+			wantErr: "notify.distributor.failure_policy",
+		},
+		{
+			name: "PipelineTemplateEmpty",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.PipelineIDTemplate = ""
+			},
+			wantErr: "notify.distributor.pipeline_id_template",
+		},
+		{
+			name: "PipelineTemplateUnknown",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.PipelineIDTemplate = "{unknown}"
+			},
+			wantErr: "notify.distributor.pipeline_id_template",
+		},
+		{
+			name: "PipelineTemplateRenderedEmpty",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.PipelineIDTemplate = "   "
+			},
+			wantErr: "notify.distributor.pipeline_id_template",
+		},
+		{
+			name: "BundleTemplate",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.BundleIDTemplate = "{unknown}"
+			},
+			wantErr: "notify.distributor.bundle_id_template",
+		},
+		{
+			name: "IdempotencyTemplate",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.IdempotencyKeyTemplate = "{unknown}"
+			},
+			wantErr: "notify.distributor.idempotency_key_template",
+		},
+		{
+			name: "ReportPathTemplatesEmpty",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.ReportPathTemplates = nil
+			},
+			wantErr: "notify.distributor.report_path_templates",
+		},
+		{
+			name: "ReportPathTemplateUnknown",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.ReportPathTemplates = []string{"{unknown}"}
+			},
+			wantErr: "notify.distributor.report_path_templates",
+		},
+		{
+			name: "ReportPathTemplateInvalidPath",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.ReportPathTemplates = []string{"/{batch_output_name}"}
+			},
+			wantErr: "notify.distributor.report_path_templates",
+		},
+		{
+			name: "ReportPathTemplateDuplicatePath",
+			mutate: func(cfg *Config) {
+				cfg.Notify.Distributor.ReportPathTemplates = []string{"latest.md", "latest.md"}
+			},
+			wantErr: "notify.distributor.report_path_templates",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := Defaults()
+			cfg.Notify.Distributor.Enabled = true
+			cfg.Notify.Distributor.PipelineIDTemplate = "weatherreporter.{artifact_group}"
+			tt.mutate(&cfg)
+
+			err := Validate(cfg)
+			if err == nil {
+				t.Fatal("Validate() error = nil, want error")
+			}
+			if !strings.Contains(err.Error(), tt.wantErr) {
+				t.Fatalf("error = %q, want %q", err.Error(), tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestDistributorTemplateRendering(t *testing.T) {
+	values := DistributorTemplateValues{
+		LocationID:      "home",
+		ReportID:        "daily",
+		RunID:           "20260607T120000Z",
+		ArtifactGroup:   "daily",
+		BatchOutputName: "daily.md",
+		ValidStartDate:  "2026-06-07",
+		ValidEndDate:    "2026-06-08",
+		ValidStartTime:  "1800",
+		ValidEndTime:    "0600",
+		ValidStartStamp: "2026-06-07T1800",
+		ValidEndStamp:   "2026-06-08T0600",
+		BundleID:        "weatherreporter.home.daily",
+	}
+
+	bundleID, err := RenderDistributorBundleID("weatherreporter.{location_id}.{report_id}", values)
+	if err != nil {
+		t.Fatalf("RenderDistributorBundleID() error = %v", err)
+	}
+	if bundleID != "weatherreporter.home.daily" {
+		t.Fatalf("bundleID = %q, want rendered value", bundleID)
+	}
+
+	pipelineID, err := RenderDistributorPipelineID("weatherreporter.{artifact_group}.{bundle_id}", values)
+	if err != nil {
+		t.Fatalf("RenderDistributorPipelineID() error = %v", err)
+	}
+	if pipelineID != "weatherreporter.daily.weatherreporter.home.daily" {
+		t.Fatalf("pipelineID = %q, want rendered pipeline ID", pipelineID)
+	}
+
+	idempotencyKey, err := RenderDistributorIdempotencyKey("{bundle_id}.{run_id}", values)
+	if err != nil {
+		t.Fatalf("RenderDistributorIdempotencyKey() error = %v", err)
+	}
+	if idempotencyKey != "weatherreporter.home.daily.20260607T120000Z" {
+		t.Fatalf("idempotencyKey = %q, want rendered run key", idempotencyKey)
+	}
+
+	reportPaths, err := RenderDistributorReportPaths([]string{
+		"{valid_start_date}/{artifact_group}/{valid_start_stamp}-{valid_end_stamp}-{run_id}.md",
+		"{valid_start_date}/{artifact_group}/latest.md",
+	}, values)
+	if err != nil {
+		t.Fatalf("RenderDistributorReportPaths() error = %v", err)
+	}
+	wantPaths := []string{
+		"2026-06-07/daily/2026-06-07T1800-2026-06-08T0600-20260607T120000Z.md",
+		"2026-06-07/daily/latest.md",
+	}
+	if strings.Join(reportPaths, "\n") != strings.Join(wantPaths, "\n") {
+		t.Fatalf("reportPaths = %#v, want %#v", reportPaths, wantPaths)
+	}
+}
+
+func TestDistributorTemplateRejectsUnknownAndMalformedVariables(t *testing.T) {
+	tests := []struct {
+		name     string
+		template string
+	}{
+		{name: "Unknown", template: "{unknown}"},
+		{name: "Unclosed", template: "{location_id"},
+		{name: "Unopened", template: "location_id}"},
+		{name: "Empty", template: "{}"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := RenderDistributorBundleID(tt.template, DistributorTemplateValues{})
+			if err == nil {
+				t.Fatal("RenderDistributorBundleID() error = nil, want error")
+			}
+		})
+	}
+}
+
+func TestDistributorReportPathValidation(t *testing.T) {
+	tests := []struct {
+		name string
+		path string
+		ok   bool
+	}{
+		{name: "Simple", path: "daily.md", ok: true},
+		{name: "Nested", path: "reports/daily.md", ok: true},
+		{name: "Empty", path: "", ok: false},
+		{name: "Absolute", path: "/reports/daily.md", ok: false},
+		{name: "WindowsAbsolute", path: "C:/reports/daily.md", ok: false},
+		{name: "Backslash", path: `reports\daily.md`, ok: false},
+		{name: "CurrentSegment", path: "reports/./daily.md", ok: false},
+		{name: "ParentSegment", path: "reports/../daily.md", ok: false},
+		{name: "EmptySegment", path: "reports//daily.md", ok: false},
+		{name: "Manifest", path: "reports/manifest.json", ok: false},
+		{name: "DistributorMetadata", path: "reports/.distributor.json", ok: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ValidateDistributorReportPath("test.path", tt.path)
+			if tt.ok && err != nil {
+				t.Fatalf("ValidateDistributorReportPath() error = %v", err)
+			}
+			if !tt.ok && err == nil {
+				t.Fatal("ValidateDistributorReportPath() error = nil, want error")
+			}
+		})
+	}
+}
+
+func TestDistributorReportPathRenderingRejectsInvalidValues(t *testing.T) {
+	tests := []struct {
+		name            string
+		batchOutputName string
+	}{
+		{name: "Absolute", batchOutputName: "/daily.md"},
+		{name: "Backslash", batchOutputName: `reports\daily.md`},
+		{name: "CurrentSegment", batchOutputName: "./daily.md"},
+		{name: "ParentSegment", batchOutputName: "../daily.md"},
+		{name: "EmptySegment", batchOutputName: "reports//daily.md"},
+		{name: "Manifest", batchOutputName: "manifest.json"},
+		{name: "DistributorMetadata", batchOutputName: ".distributor.json"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := RenderDistributorReportPaths([]string{"{batch_output_name}"}, DistributorTemplateValues{
+				BatchOutputName: tt.batchOutputName,
+			})
+			if err == nil {
+				t.Fatal("RenderDistributorReportPaths() error = nil, want error")
+			}
+		})
+	}
+}
+
+func TestLoadFileLoadsSecretsBeforeReturningNotifyConfig(t *testing.T) {
+	dir := t.TempDir()
+	secretsDir := filepath.Join(dir, "secrets")
+	if err := os.Mkdir(secretsDir, 0o700); err != nil {
+		t.Fatalf("create secrets directory: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(secretsDir, "DISTRIBUTOR_UPLOAD_TOKEN"), []byte("loaded-token"), 0o600); err != nil {
+		t.Fatalf("write secret: %v", err)
+	}
+	path := filepath.Join(dir, "config.yml")
+	configYAML := "secrets:\n" +
+		"  directory: " + secretsDir + "\n" +
+		"notify:\n" +
+		"  distributor:\n" +
+		"    enabled: true\n" +
+		"    pipeline_id_template: weatherreporter.{artifact_group}\n"
+	if err := os.WriteFile(path, []byte(configYAML), 0o600); err != nil {
+		t.Fatalf("write config fixture: %v", err)
+	}
+
+	t.Setenv("DISTRIBUTOR_UPLOAD_TOKEN", "")
+	cfg, err := LoadFile(path)
+	if err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+	if cfg.Notify.Distributor.TokenEnv != "DISTRIBUTOR_UPLOAD_TOKEN" {
+		t.Fatalf("TokenEnv = %q, want DISTRIBUTOR_UPLOAD_TOKEN", cfg.Notify.Distributor.TokenEnv)
+	}
+	if got := os.Getenv(cfg.Notify.Distributor.TokenEnv); got != "loaded-token" {
+		t.Fatalf("environment value = %q, want loaded-token", got)
+	}
+}
+
+func TestLoadSecretsDisabledLeavesEnvironmentUnchanged(t *testing.T) {
+	t.Setenv("WEATHERREPORTER_DISABLED_SECRET", "original")
+
+	if err := loadSecrets(SecretsConfig{}); err != nil {
+		t.Fatalf("loadSecrets() error = %v", err)
+	}
+	if got := os.Getenv("WEATHERREPORTER_DISABLED_SECRET"); got != "original" {
+		t.Fatalf("environment value = %q, want original", got)
+	}
+}
+
+func TestLoadFileLoadsSecretsDirectory(t *testing.T) {
+	dir := t.TempDir()
+	secretsDir := filepath.Join(dir, "secrets")
+	if err := os.Mkdir(secretsDir, 0o700); err != nil {
+		t.Fatalf("create secrets directory: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(secretsDir, "WEATHERREPORTER_SECRET"), []byte("from-file"), 0o600); err != nil {
+		t.Fatalf("write secret: %v", err)
+	}
+	path := filepath.Join(dir, "config.yml")
+	if err := os.WriteFile(path, []byte("secrets:\n  directory: "+secretsDir+"\n"), 0o600); err != nil {
+		t.Fatalf("write config fixture: %v", err)
+	}
+
+	t.Setenv("WEATHERREPORTER_SECRET", "")
+	if _, err := LoadFile(path); err != nil {
+		t.Fatalf("LoadFile() error = %v", err)
+	}
+	if got := os.Getenv("WEATHERREPORTER_SECRET"); got != "from-file" {
+		t.Fatalf("environment value = %q, want from-file", got)
+	}
+}
+
+func TestLoadSecretsOverwritesExistingEnvironment(t *testing.T) {
+	dir := t.TempDir()
+	if err := os.WriteFile(filepath.Join(dir, "WEATHERREPORTER_SECRET"), []byte("from-file"), 0o600); err != nil {
+		t.Fatalf("write secret: %v", err)
+	}
+	t.Setenv("WEATHERREPORTER_SECRET", "existing")
+
+	if err := loadSecrets(SecretsConfig{Directory: dir}); err != nil {
+		t.Fatalf("loadSecrets() error = %v", err)
+	}
+	if got := os.Getenv("WEATHERREPORTER_SECRET"); got != "from-file" {
+		t.Fatalf("environment value = %q, want from-file", got)
+	}
+}
+
+func TestLoadSecretsTrimsOneTrailingLineEnding(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{name: "LF", input: "value\n", want: "value"},
+		{name: "CRLF", input: "value\r\n", want: "value"},
+		{name: "TwoLF", input: "value\n\n", want: "value\n"},
+		{name: "LoneCR", input: "value\r", want: "value\r"},
+		{name: "NoNewline", input: "value", want: "value"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			dir := t.TempDir()
+			if err := os.WriteFile(filepath.Join(dir, "WEATHERREPORTER_SECRET"), []byte(tt.input), 0o600); err != nil {
+				t.Fatalf("write secret: %v", err)
+			}
+			t.Setenv("WEATHERREPORTER_SECRET", "")
+
+			if err := loadSecrets(SecretsConfig{Directory: dir}); err != nil {
+				t.Fatalf("loadSecrets() error = %v", err)
+			}
+			if got := os.Getenv("WEATHERREPORTER_SECRET"); got != tt.want {
+				t.Fatalf("environment value = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestLoadSecretsRejectsInvalidDirectoryEntries(t *testing.T) {
+	tests := []struct {
+		name    string
+		setup   func(t *testing.T, dir string)
+		wantErr string
+	}{
+		{
+			name: "InvalidFilename",
+			setup: func(t *testing.T, dir string) {
+				if err := os.WriteFile(filepath.Join(dir, "1INVALID"), []byte("secret-value"), 0o600); err != nil {
+					t.Fatalf("write invalid secret: %v", err)
+				}
+			},
+			wantErr: "invalid environment variable name",
+		},
+		{
+			name: "Subdirectory",
+			setup: func(t *testing.T, dir string) {
+				if err := os.Mkdir(filepath.Join(dir, "SUBDIR"), 0o700); err != nil {
+					t.Fatalf("create subdirectory: %v", err)
+				}
+			},
+			wantErr: "not a directory",
+		},
+		{
+			name: "Symlink",
+			setup: func(t *testing.T, dir string) {
+				target := filepath.Join(dir, "TARGET")
+				if err := os.WriteFile(target, []byte("secret-value"), 0o600); err != nil {
+					t.Fatalf("write target: %v", err)
+				}
+				if err := os.Symlink(target, filepath.Join(dir, "SYMLINK")); err != nil {
+					t.Fatalf("create symlink: %v", err)
+				}
+			},
+			wantErr: "not a symlink",
+		},
+		{
+			name: "Unreadable",
+			setup: func(t *testing.T, dir string) {
+				path := filepath.Join(dir, "UNREADABLE")
+				if err := os.WriteFile(path, []byte("secret-value"), 0o600); err != nil {
+					t.Fatalf("write unreadable secret: %v", err)
+				}
+				if err := os.Chmod(path, 0o000); err != nil {
+					t.Fatalf("chmod unreadable secret: %v", err)
+				}
+				t.Cleanup(func() {
+					_ = os.Chmod(path, 0o600)
+				})
+			},
+			wantErr: "read secret file",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			dir := t.TempDir()
+			tt.setup(t, dir)
+
+			err := loadSecrets(SecretsConfig{Directory: dir})
+			if err == nil {
+				t.Fatal("loadSecrets() error = nil, want error")
+			}
+			if !strings.Contains(err.Error(), tt.wantErr) {
+				t.Fatalf("error = %q, want %q", err.Error(), tt.wantErr)
+			}
+			if strings.Contains(err.Error(), "secret-value") {
+				t.Fatalf("error = %q, want no secret value", err.Error())
+			}
+		})
+	}
+}
+
+func TestLoadSecretsRejectsMissingDirectory(t *testing.T) {
+	err := loadSecrets(SecretsConfig{Directory: filepath.Join(t.TempDir(), "missing")})
+	if err == nil {
+		t.Fatal("loadSecrets() error = nil, want missing directory error")
+	}
+	if !strings.Contains(err.Error(), "read secrets directory") {
+		t.Fatalf("error = %q, want read secrets directory context", err.Error())
+	}
+}

internal/config/defaults.go

@@ -0,0 +1,70 @@
+package config
+
+import "time"
+
+const DefaultPath = "/usr/local/etc/weatherreporter/config.yml"
+
+func Defaults() Config {
+	return Config{
+		WeatherAPI: WeatherAPIConfig{
+			Timeout:   10 * time.Second,
+			Precision: 1,
+			Units:     "us",
+			Timezone:  "America/Chicago",
+			Format:    "json",
+		},
+		Location: LocationConfig{
+			ID:     "home",
+			Name:   "Brentwood",
+			Region: "St. Louis Metro",
+		},
+		Secrets: SecretsConfig{
+			Directory: "",
+		},
+		Notify: NotifyConfig{
+			Distributor: DistributorNotifyConfig{
+				Enabled:                false,
+				Endpoint:               "https://distributor.example.com",
+				TokenEnv:               "DISTRIBUTOR_UPLOAD_TOKEN",
+				Timeout:                30 * time.Second,
+				FailurePolicy:          NotifyFailureError,
+				PipelineIDTemplate:     "",
+				BundleIDTemplate:       "weatherreporter.{location_id}.{report_id}",
+				IdempotencyKeyTemplate: "{bundle_id}.{run_id}",
+				ReportPathTemplates: []string{
+					"{valid_start_date}/{artifact_group}/{valid_start_date}-{artifact_group}-{run_id}.md",
+				},
+			},
+		},
+		MissingSource: MissingSourceConfig{
+			Default: MissingSourceWarn,
+			Sources: map[string]MissingSourcePolicy{},
+		},
+		Scriptorium: ScriptoriumConfig{
+			Binary:  "scriptorium",
+			Timeout: 2 * time.Minute,
+		},
+		Workspace: WorkspaceConfig{
+			Root:             "workspace",
+			SnapshotsDir:     "snapshots",
+			ReportsDir:       "reports",
+			DataPackagesDir:  "data-packages",
+			PreflightDir:     "preflight",
+			NotificationsDir: "notifications",
+		},
+		Dayparts: []DaypartConfig{
+			{Name: "overnight", Start: "00:00", End: "06:00"},
+			{Name: "morning", Start: "06:00", End: "10:00"},
+			{Name: "midday", Start: "10:00", End: "15:00"},
+			{Name: "afternoon", Start: "15:00", End: "17:00"},
+			{Name: "evening", Start: "17:00", End: "24:00"},
+		},
+		RecentChange: RecentChangeConfig{
+			TemperatureDegrees:       5,
+			PrecipProbabilityPoints:  20,
+			WindGustMilesPerHour:     10,
+			PrecipTimingShiftMinutes: 120,
+		},
+		Reports: map[string]ReportConfig{},
+	}
+}

internal/config/load.go

@@ -0,0 +1,72 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"gopkg.in/yaml.v3"
+)
+
+type LoadOptions struct {
+	Path     string
+	Units    string
+	Timezone string
+}
+
+func Load(opts LoadOptions) (Config, error) {
+	cfg := Defaults()
+
+	path := opts.Path
+	if path == "" {
+		path = DefaultPath
+	}
+
+	if err := mergeFile(&cfg, path); err != nil {
+		if opts.Path != "" || !errors.Is(err, os.ErrNotExist) {
+			return Config{}, err
+		}
+	}
+
+	if opts.Units != "" {
+		cfg.WeatherAPI.Units = opts.Units
+	}
+	if opts.Timezone != "" {
+		cfg.WeatherAPI.Timezone = opts.Timezone
+	}
+
+	if err := normalizeReportModules(&cfg); err != nil {
+		return Config{}, err
+	}
+
+	if err := loadSecrets(cfg.Secrets); err != nil {
+		return Config{}, err
+	}
+
+	if err := Validate(cfg); err != nil {
+		return Config{}, err
+	}
+
+	return cfg, nil
+}
+
+func LoadFile(path string) (Config, error) {
+	return Load(LoadOptions{Path: path})
+}
+
+func mergeFile(cfg *Config, path string) error {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("read config %q: %w", path, err)
+	}
+	if err := yaml.Unmarshal(data, cfg); err != nil {
+		return fmt.Errorf("parse config %q: %w", path, err)
+	}
+	if cfg.MissingSource.Sources == nil {
+		cfg.MissingSource.Sources = map[string]MissingSourcePolicy{}
+	}
+	if cfg.Reports == nil {
+		cfg.Reports = map[string]ReportConfig{}
+	}
+	return nil
+}

internal/config/notify_templates.go

@@ -0,0 +1,201 @@
+package config
+
+import (
+	"fmt"
+	"path/filepath"
+	"strings"
+)
+
+type DistributorTemplateValues struct {
+	LocationID      string
+	ReportID        string
+	RunID           string
+	ArtifactGroup   string
+	BatchOutputName string
+	ValidStartDate  string
+	ValidEndDate    string
+	ValidStartTime  string
+	ValidEndTime    string
+	ValidStartStamp string
+	ValidEndStamp   string
+	BundleID        string
+}
+
+var distributorTemplateVariables = map[string]struct{}{
+	"location_id":       {},
+	"report_id":         {},
+	"run_id":            {},
+	"artifact_group":    {},
+	"batch_output_name": {},
+	"valid_start_date":  {},
+	"valid_end_date":    {},
+	"valid_start_time":  {},
+	"valid_end_time":    {},
+	"valid_start_stamp": {},
+	"valid_end_stamp":   {},
+}
+
+var distributorIdempotencyTemplateVariables = map[string]struct{}{
+	"location_id":       {},
+	"report_id":         {},
+	"run_id":            {},
+	"artifact_group":    {},
+	"batch_output_name": {},
+	"valid_start_date":  {},
+	"valid_end_date":    {},
+	"valid_start_time":  {},
+	"valid_end_time":    {},
+	"valid_start_stamp": {},
+	"valid_end_stamp":   {},
+	"bundle_id":         {},
+}
+
+var distributorPipelineTemplateVariables = distributorIdempotencyTemplateVariables
+
+func RenderDistributorBundleID(template string, values DistributorTemplateValues) (string, error) {
+	return renderDistributorTemplate("notify.distributor.bundle_id_template", template, values, distributorTemplateVariables)
+}
+
+func RenderDistributorPipelineID(template string, values DistributorTemplateValues) (string, error) {
+	rendered, err := renderDistributorTemplate("notify.distributor.pipeline_id_template", template, values, distributorPipelineTemplateVariables)
+	if err != nil {
+		return "", err
+	}
+	if strings.TrimSpace(rendered) == "" {
+		return "", fmt.Errorf("notify.distributor.pipeline_id_template renders an empty pipeline id")
+	}
+	return rendered, nil
+}
+
+func RenderDistributorIdempotencyKey(template string, values DistributorTemplateValues) (string, error) {
+	return renderDistributorTemplate("notify.distributor.idempotency_key_template", template, values, distributorIdempotencyTemplateVariables)
+}
+
+func RenderDistributorReportPaths(templates []string, values DistributorTemplateValues) ([]string, error) {
+	if len(templates) == 0 {
+		return nil, fmt.Errorf("notify.distributor.report_path_templates must contain at least one entry")
+	}
+	paths := make([]string, 0, len(templates))
+	seen := make(map[string]struct{}, len(templates))
+	for i, template := range templates {
+		name := fmt.Sprintf("notify.distributor.report_path_templates[%d]", i)
+		rendered, err := renderDistributorTemplate(name, template, values, distributorTemplateVariables)
+		if err != nil {
+			return nil, err
+		}
+		if err := ValidateDistributorReportPath(name, rendered); err != nil {
+			return nil, err
+		}
+		if _, ok := seen[rendered]; ok {
+			return nil, fmt.Errorf("notify.distributor.report_path_templates renders duplicate path %q", rendered)
+		}
+		seen[rendered] = struct{}{}
+		paths = append(paths, rendered)
+	}
+	return paths, nil
+}
+
+func validateDistributorTemplate(name, template string, allowed map[string]struct{}) error {
+	_, err := renderDistributorTemplate(name, template, DistributorTemplateValues{}, allowed)
+	return err
+}
+
+func renderDistributorTemplate(name, template string, values DistributorTemplateValues, allowed map[string]struct{}) (string, error) {
+	var rendered strings.Builder
+	for i := 0; i < len(template); {
+		switch template[i] {
+		case '{':
+			end := strings.IndexByte(template[i+1:], '}')
+			if end < 0 {
+				return "", fmt.Errorf("%s contains an unclosed template variable", name)
+			}
+			variable := template[i+1 : i+1+end]
+			if variable == "" {
+				return "", fmt.Errorf("%s contains an empty template variable", name)
+			}
+			if _, ok := allowed[variable]; !ok {
+				return "", fmt.Errorf("%s contains unknown template variable %q", name, variable)
+			}
+			rendered.WriteString(distributorTemplateValue(variable, values))
+			i += end + 2
+		case '}':
+			return "", fmt.Errorf("%s contains an unopened template variable", name)
+		default:
+			rendered.WriteByte(template[i])
+			i++
+		}
+	}
+	return rendered.String(), nil
+}
+
+func distributorTemplateValue(variable string, values DistributorTemplateValues) string {
+	switch variable {
+	case "location_id":
+		return values.LocationID
+	case "report_id":
+		return values.ReportID
+	case "run_id":
+		return values.RunID
+	case "artifact_group":
+		return values.ArtifactGroup
+	case "batch_output_name":
+		return values.BatchOutputName
+	case "valid_start_date":
+		return values.ValidStartDate
+	case "valid_end_date":
+		return values.ValidEndDate
+	case "valid_start_time":
+		return values.ValidStartTime
+	case "valid_end_time":
+		return values.ValidEndTime
+	case "valid_start_stamp":
+		return values.ValidStartStamp
+	case "valid_end_stamp":
+		return values.ValidEndStamp
+	case "bundle_id":
+		return values.BundleID
+	default:
+		return ""
+	}
+}
+
+func ValidateDistributorReportPath(name, path string) error {
+	if path == "" {
+		return fmt.Errorf("%s renders an empty path", name)
+	}
+	if isDistributorAbsolutePath(path) {
+		return fmt.Errorf("%s must render a relative path", name)
+	}
+	if strings.Contains(path, "\\") {
+		return fmt.Errorf("%s must not render backslashes", name)
+	}
+
+	segments := strings.Split(path, "/")
+	for _, segment := range segments {
+		if segment == "" {
+			return fmt.Errorf("%s must not render empty path segments", name)
+		}
+		if segment == "." || segment == ".." {
+			return fmt.Errorf("%s must not render . or .. path segments", name)
+		}
+		if segment == "manifest.json" || segment == ".distributor.json" {
+			return fmt.Errorf("%s must not render reserved path segment %q", name, segment)
+		}
+	}
+
+	return nil
+}
+
+func isDistributorAbsolutePath(path string) bool {
+	if filepath.IsAbs(path) || strings.HasPrefix(path, "/") {
+		return true
+	}
+	if len(path) >= 3 && isASCIIAlpha(path[0]) && path[1] == ':' && (path[2] == '/' || path[2] == '\\') {
+		return true
+	}
+	return false
+}
+
+func isASCIIAlpha(ch byte) bool {
+	return (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z')
+}

internal/config/reports.go

@@ -0,0 +1,125 @@
+package config
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/briefing"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gopkg.in/yaml.v3"
+)
+
+func (cfg Config) ReportModuleOverrides() map[report.ID][]module.ConfigItem {
+	overrides := map[report.ID][]module.ConfigItem{}
+	for key, reportCfg := range cfg.Reports {
+		if !reportCfg.deterministicModulesSet {
+			continue
+		}
+		id, err := reportIDForConfigKey(key)
+		if err != nil {
+			continue
+		}
+		items := make([]module.ConfigItem, 0, len(reportCfg.DeterministicModules))
+		for _, item := range reportCfg.DeterministicModules {
+			items = append(items, module.ConfigItem{ID: item.ID, Options: item.Options})
+		}
+		overrides[id] = items
+	}
+	return overrides
+}
+
+func normalizeReportModules(cfg *Config) error {
+	if cfg.Reports == nil {
+		cfg.Reports = map[string]ReportConfig{}
+	}
+	moduleRegistry, err := briefing.DefaultModuleRegistry()
+	if err != nil {
+		return fmt.Errorf("initialize module registry: %w", err)
+	}
+	reportRegistry := report.DefaultRegistry()
+	seenReports := map[report.ID]string{}
+	for key, reportCfg := range cfg.Reports {
+		reportID, err := reportIDForConfigKey(key)
+		if err != nil {
+			return err
+		}
+		if previous, ok := seenReports[reportID]; ok {
+			return fmt.Errorf("reports.%s duplicates report override %q", key, previous)
+		}
+		seenReports[reportID] = key
+		if _, err := reportRegistry.Lookup(reportID); err != nil {
+			return fmt.Errorf("reports.%s: %w", key, err)
+		}
+		if !reportCfg.deterministicModulesSet {
+			continue
+		}
+		items := make([]module.ConfigItem, 0, len(reportCfg.DeterministicModules))
+		for i, rawItem := range reportCfg.DeterministicModules {
+			options, err := normalizeModuleOptions(moduleRegistry, rawItem.ID, rawItem.Options)
+			if err != nil {
+				return fmt.Errorf("reports.%s.deterministic_modules[%d]: %w", key, i, err)
+			}
+			reportCfg.DeterministicModules[i].Options = options
+			items = append(items, module.ConfigItem{ID: rawItem.ID, Options: options})
+		}
+		if err := moduleRegistry.ValidateComposition(reportID, items); err != nil {
+			return fmt.Errorf("reports.%s.deterministic_modules: %w", key, err)
+		}
+		cfg.Reports[key] = reportCfg
+	}
+	return nil
+}
+
+func normalizeModuleOptions(registry briefing.ModuleRegistry, id module.ID, raw any) (any, error) {
+	if raw == nil {
+		return nil, nil
+	}
+	definition, err := registry.Lookup(id)
+	if err != nil {
+		return nil, err
+	}
+	if definition.DefaultOptions == nil {
+		return nil, fmt.Errorf("module %q does not accept options", id)
+	}
+	optionType := reflect.TypeOf(definition.DefaultOptions)
+	normalized, err := decodeKnownOptions(raw, optionType)
+	if err != nil {
+		return nil, fmt.Errorf("module %q options are invalid: %w", id, err)
+	}
+	return normalized, nil
+}
+
+func decodeKnownOptions(raw any, optionType reflect.Type) (any, error) {
+	data, err := yaml.Marshal(raw)
+	if err != nil {
+		return nil, err
+	}
+	target := reflect.New(optionType)
+	decoder := yaml.NewDecoder(bytes.NewReader(data))
+	decoder.KnownFields(true)
+	if err := decoder.Decode(target.Interface()); err != nil {
+		return nil, err
+	}
+	return target.Elem().Interface(), nil
+}
+
+func reportIDForConfigKey(key string) (report.ID, error) {
+	normalized := strings.ReplaceAll(strings.TrimSpace(strings.ToLower(key)), "-", "_")
+	switch normalized {
+	case "daily", "daily_today":
+		return report.DailyToday, nil
+	case "tomorrow", "daily_tomorrow":
+		return report.DailyTomorrow, nil
+	case "three_day", "three_day_outlook":
+		return report.ThreeDay, nil
+	case "weekend", "weekend_outlook":
+		return report.Weekend, nil
+	case "storm", "storm_report":
+		return report.Storm, nil
+	default:
+		return "", fmt.Errorf("reports.%s is not a known report", key)
+	}
+}

internal/config/secrets.go

@@ -0,0 +1,63 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+var secretNamePattern = regexp.MustCompile(`^[A-Za-z_][A-Za-z0-9_]*$`)
+
+func loadSecrets(cfg SecretsConfig) error {
+	if cfg.Directory == "" {
+		return nil
+	}
+
+	entries, err := os.ReadDir(cfg.Directory)
+	if err != nil {
+		return fmt.Errorf("read secrets directory %q: %w", cfg.Directory, err)
+	}
+
+	for _, entry := range entries {
+		name := entry.Name()
+		if name == "" {
+			return fmt.Errorf("secrets directory %q contains an empty filename", cfg.Directory)
+		}
+		if !secretNamePattern.MatchString(name) {
+			return fmt.Errorf("secret file %q has invalid environment variable name", name)
+		}
+		if entry.Type()&os.ModeSymlink != 0 {
+			return fmt.Errorf("secret file %q must be a regular file, not a symlink", name)
+		}
+		if entry.IsDir() {
+			return fmt.Errorf("secret file %q must be a regular file, not a directory", name)
+		}
+
+		info, err := entry.Info()
+		if err != nil {
+			return fmt.Errorf("inspect secret file %q: %w", name, err)
+		}
+		if !info.Mode().IsRegular() {
+			return fmt.Errorf("secret file %q must be a regular file", name)
+		}
+
+		path := filepath.Join(cfg.Directory, name)
+		data, err := os.ReadFile(path)
+		if err != nil {
+			return fmt.Errorf("read secret file %q: %w", name, err)
+		}
+		value := string(data)
+		if strings.HasSuffix(value, "\r\n") {
+			value = strings.TrimSuffix(value, "\r\n")
+		} else {
+			value = strings.TrimSuffix(value, "\n")
+		}
+		if err := os.Setenv(name, value); err != nil {
+			return fmt.Errorf("set environment variable from secret file %q: %w", name, err)
+		}
+	}
+
+	return nil
+}

internal/config/validate.go

@@ -0,0 +1,162 @@
+package config
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+func Validate(cfg Config) error {
+	if err := normalizeReportModules(&cfg); err != nil {
+		return err
+	}
+	if cfg.WeatherAPI.BaseURL != "" {
+		parsed, err := url.Parse(cfg.WeatherAPI.BaseURL)
+		if err != nil || parsed.Scheme == "" || parsed.Host == "" {
+			return fmt.Errorf("weather_api.base_url must be an absolute URL")
+		}
+	}
+	if cfg.WeatherAPI.Timeout <= 0 {
+		return fmt.Errorf("weather_api.timeout must be greater than zero")
+	}
+	if cfg.WeatherAPI.Precision < 0 {
+		return fmt.Errorf("weather_api.precision must be zero or greater")
+	}
+	if cfg.WeatherAPI.Units == "" {
+		return fmt.Errorf("weather_api.units is required")
+	}
+	if cfg.WeatherAPI.Timezone == "" {
+		return fmt.Errorf("weather_api.timezone is required")
+	}
+	if _, err := timeutil.LoadLocation(cfg.WeatherAPI.Timezone); err != nil {
+		return fmt.Errorf("weather_api.timezone %q is invalid: %w", cfg.WeatherAPI.Timezone, err)
+	}
+	if cfg.WeatherAPI.Format == "" {
+		return fmt.Errorf("weather_api.format is required")
+	}
+	if cfg.WeatherAPI.Format != "json" {
+		return fmt.Errorf("weather_api.format must be json")
+	}
+
+	if err := validatePolicy("missing_source.default", cfg.MissingSource.Default); err != nil {
+		return err
+	}
+	for source, policy := range cfg.MissingSource.Sources {
+		if strings.TrimSpace(source) == "" {
+			return fmt.Errorf("missing_source.sources contains an empty source name")
+		}
+		if err := validatePolicy("missing_source.sources."+source, policy); err != nil {
+			return err
+		}
+	}
+
+	if err := validateDistributorNotify(cfg.Notify.Distributor); err != nil {
+		return err
+	}
+
+	if cfg.Scriptorium.Binary == "" {
+		return fmt.Errorf("scriptorium.binary is required")
+	}
+	if cfg.Scriptorium.Timeout <= 0 {
+		return fmt.Errorf("scriptorium.timeout must be greater than zero")
+	}
+	if cfg.Workspace.Root == "" {
+		return fmt.Errorf("workspace.root is required")
+	}
+	if len(cfg.Dayparts) == 0 {
+		return fmt.Errorf("dayparts must contain at least one entry")
+	}
+	for i, daypart := range cfg.Dayparts {
+		if strings.TrimSpace(daypart.Name) == "" {
+			return fmt.Errorf("dayparts[%d].name is required", i)
+		}
+		if _, err := timeutil.ParseClock(daypart.Start); err != nil {
+			return fmt.Errorf("dayparts[%d].start is invalid: %w", i, err)
+		}
+		if _, err := timeutil.ParseClock(daypart.End); err != nil {
+			return fmt.Errorf("dayparts[%d].end is invalid: %w", i, err)
+		}
+	}
+	return nil
+}
+
+func validateDistributorNotify(cfg DistributorNotifyConfig) error {
+	if !cfg.Enabled {
+		return nil
+	}
+
+	parsed, err := url.Parse(cfg.Endpoint)
+	if err != nil || parsed.Scheme == "" || parsed.Host == "" {
+		return fmt.Errorf("notify.distributor.endpoint must be an absolute URL when enabled")
+	}
+	if cfg.TokenEnv == "" {
+		return fmt.Errorf("notify.distributor.token_env is required when enabled")
+	}
+	if !secretNamePattern.MatchString(cfg.TokenEnv) {
+		return fmt.Errorf("notify.distributor.token_env must be a valid environment variable name")
+	}
+	if cfg.Timeout <= 0 {
+		return fmt.Errorf("notify.distributor.timeout must be greater than zero when enabled")
+	}
+	if cfg.FailurePolicy != NotifyFailureError {
+		return fmt.Errorf("notify.distributor.failure_policy must be error when enabled")
+	}
+	if cfg.PipelineIDTemplate == "" {
+		return fmt.Errorf("notify.distributor.pipeline_id_template is required when enabled")
+	}
+	if err := validateDistributorTemplate("notify.distributor.pipeline_id_template", cfg.PipelineIDTemplate, distributorPipelineTemplateVariables); err != nil {
+		return err
+	}
+	if cfg.BundleIDTemplate == "" {
+		return fmt.Errorf("notify.distributor.bundle_id_template is required when enabled")
+	}
+	if err := validateDistributorTemplate("notify.distributor.bundle_id_template", cfg.BundleIDTemplate, distributorTemplateVariables); err != nil {
+		return err
+	}
+	if cfg.IdempotencyKeyTemplate == "" {
+		return fmt.Errorf("notify.distributor.idempotency_key_template is required when enabled")
+	}
+	if err := validateDistributorTemplate("notify.distributor.idempotency_key_template", cfg.IdempotencyKeyTemplate, distributorIdempotencyTemplateVariables); err != nil {
+		return err
+	}
+	if len(cfg.ReportPathTemplates) == 0 {
+		return fmt.Errorf("notify.distributor.report_path_templates must contain at least one entry when enabled")
+	}
+	values := DistributorTemplateValues{
+		LocationID:      "location",
+		ReportID:        "report",
+		RunID:           "run",
+		ArtifactGroup:   "artifact",
+		BatchOutputName: "report.md",
+		ValidStartDate:  "2026-05-29",
+		ValidEndDate:    "2026-05-30",
+		ValidStartTime:  "0000",
+		ValidEndTime:    "0000",
+		ValidStartStamp: "2026-05-29T0000",
+		ValidEndStamp:   "2026-05-30T0000",
+	}
+	bundleID, err := RenderDistributorBundleID(cfg.BundleIDTemplate, values)
+	if err != nil {
+		return err
+	}
+	values.BundleID = bundleID
+	if _, err := RenderDistributorPipelineID(cfg.PipelineIDTemplate, values); err != nil {
+		return err
+	}
+	if _, err := RenderDistributorReportPaths(cfg.ReportPathTemplates, values); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func validatePolicy(name string, policy MissingSourcePolicy) error {
+	switch policy {
+	case MissingSourceError, MissingSourceWarn, MissingSourceNone:
+		return nil
+	default:
+		return fmt.Errorf("%s must be one of error, warn, or none", name)
+	}
+}

internal/facts/facts.go

@@ -0,0 +1,141 @@
+// Package facts defines collected and derived report facts.
+package facts
+
+import (
+	"fmt"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type CollectedFacts struct {
+	FetchedAt    time.Time
+	Observation  *weatherdata.Observation
+	Current      *weatherdata.Current
+	Hourly       *weatherdata.ForecastRun
+	Narrative    *weatherdata.ForecastRun
+	Alerts       *weatherdata.AlertRun
+	Discussion   *weatherdata.Discussion
+	Daily        *weatherdata.ForecastRun
+	WeatherStory *weatherdata.WeatherStory
+
+	SourceProvenance []weatherdata.Source
+	SourceWarnings   []weatherdata.SourceWarning
+}
+
+func BuildCollected(bundle *weatherdata.Bundle) CollectedFacts {
+	if bundle == nil {
+		return CollectedFacts{}
+	}
+	return CollectedFacts{
+		FetchedAt:        bundle.FetchedAt,
+		Observation:      bundle.Observation,
+		Current:          bundle.Current,
+		Hourly:           bundle.Hourly,
+		Narrative:        bundle.Narrative,
+		Alerts:           bundle.Alerts,
+		Discussion:       bundle.Discussion,
+		Daily:            bundle.Daily,
+		WeatherStory:     bundle.WeatherStory,
+		SourceProvenance: append([]weatherdata.Source(nil), bundle.Sources...),
+		SourceWarnings:   append([]weatherdata.SourceWarning(nil), bundle.Warnings...),
+	}
+}
+
+func (f CollectedFacts) Bundle() *weatherdata.Bundle {
+	return &weatherdata.Bundle{
+		FetchedAt:    f.FetchedAt,
+		Observation:  f.Observation,
+		Current:      f.Current,
+		Hourly:       f.Hourly,
+		Narrative:    f.Narrative,
+		Alerts:       f.Alerts,
+		Discussion:   f.Discussion,
+		Daily:        f.Daily,
+		WeatherStory: f.WeatherStory,
+		Sources:      append([]weatherdata.Source(nil), f.SourceProvenance...),
+		Warnings:     append([]weatherdata.SourceWarning(nil), f.SourceWarnings...),
+	}
+}
+
+type BuildDerivedRequest struct {
+	Resolved  report.Resolved
+	Timezone  string
+	Dayparts  []forecast.DaypartDefinition
+	Collected CollectedFacts
+}
+
+type DerivedFacts struct {
+	ValidPeriodHourlyPeriods    []weatherdata.ForecastPeriod
+	ValidPeriodNarrativePeriods []weatherdata.ForecastPeriod
+	ValidPeriodDailyPeriods     []weatherdata.ForecastPeriod
+	AlertOverlaps               []forecast.AlertOverlap
+	DailySummaries              []forecast.DailySummary
+	DaypartSummaries            []forecast.DaypartSummary
+	PrecipTiming                forecast.PrecipTiming
+	StormWindowSummary          *forecast.DaypartSummary
+}
+
+func (f DerivedFacts) FirstDailySummary() *forecast.DailySummary {
+	if len(f.DailySummaries) == 0 {
+		return nil
+	}
+	return &f.DailySummaries[0]
+}
+
+func BuildDerived(req BuildDerivedRequest) (DerivedFacts, error) {
+	if !req.Resolved.ValidPeriod.IsValid() {
+		return DerivedFacts{}, fmt.Errorf("resolved valid period is required")
+	}
+	location, err := timeutil.LoadLocation(req.Timezone)
+	if err != nil {
+		return DerivedFacts{}, fmt.Errorf("load report timezone %q: %w", req.Timezone, err)
+	}
+	bundle := req.Collected.Bundle()
+	period := req.Resolved.ValidPeriod
+	derived := DerivedFacts{
+		ValidPeriodHourlyPeriods:    forecast.SelectHourlyPeriods(req.Collected.Hourly, period),
+		ValidPeriodNarrativePeriods: forecast.SelectHourlyPeriods(req.Collected.Narrative, period),
+		ValidPeriodDailyPeriods:     forecast.SelectHourlyPeriods(req.Collected.Daily, period),
+		AlertOverlaps:               forecast.AlertOverlaps(req.Collected.Alerts, period),
+	}
+	derived.PrecipTiming = forecast.BuildPrecipTiming(derived.ValidPeriodHourlyPeriods)
+
+	switch req.Resolved.Definition.ID {
+	case report.DailyToday, report.DailyTomorrow:
+		summary, err := forecast.BuildDailySummary(bundle, period.Start, location, req.Dayparts)
+		if err != nil {
+			return DerivedFacts{}, err
+		}
+		derived.DailySummaries = []forecast.DailySummary{*summary}
+	case report.ThreeDay, report.Weekend:
+		summaries, err := forecast.BuildPeriodDailySummaries(bundle, period, location, req.Dayparts)
+		if err != nil {
+			return DerivedFacts{}, err
+		}
+		derived.DailySummaries = summaries
+	case report.Storm:
+		summary := forecast.SummarizeDaypart("storm window", period, derived.ValidPeriodHourlyPeriods)
+		summary.AlertOverlaps = derived.AlertOverlaps
+		derived.StormWindowSummary = &summary
+	default:
+		return DerivedFacts{}, fmt.Errorf("derived facts are not implemented for report %q", req.Resolved.Definition.ID)
+	}
+
+	derived.DaypartSummaries = collectDaypartSummaries(derived)
+	return derived, nil
+}
+
+func collectDaypartSummaries(derived DerivedFacts) []forecast.DaypartSummary {
+	var out []forecast.DaypartSummary
+	for _, summary := range derived.DailySummaries {
+		out = append(out, summary.Dayparts...)
+	}
+	if derived.StormWindowSummary != nil {
+		out = append(out, *derived.StormWindowSummary)
+	}
+	return out
+}

internal/facts/facts_test.go

@@ -0,0 +1,253 @@
+package facts
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+func TestBuildCollectedCopiesBundleFactsAndKeepsSourcesSeparate(t *testing.T) {
+	fetchedAt := mustParse("2026-05-29T10:00:00Z")
+	bundle := &weatherdata.Bundle{
+		FetchedAt: fetchedAt,
+		Current:   &weatherdata.Current{ConditionText: "Clear"},
+		Hourly:    &weatherdata.ForecastRun{Product: "hourly"},
+		Sources:   []weatherdata.Source{{Name: "hourly"}},
+		Warnings:  []weatherdata.SourceWarning{{Source: "discussion", Code: "missing_source"}},
+	}
+
+	collected := BuildCollected(bundle)
+	if collected.FetchedAt != fetchedAt || collected.Current.ConditionText != "Clear" || collected.Hourly.Product != "hourly" {
+		t.Fatalf("CollectedFacts = %#v, want source facts copied from bundle", collected)
+	}
+	if len(collected.SourceProvenance) != 1 || collected.SourceProvenance[0].Name != "hourly" {
+		t.Fatalf("SourceProvenance = %#v, want hourly source", collected.SourceProvenance)
+	}
+	if len(collected.SourceWarnings) != 1 || collected.SourceWarnings[0].Source != "discussion" {
+		t.Fatalf("SourceWarnings = %#v, want discussion warning", collected.SourceWarnings)
+	}
+
+	bundle.Sources[0].Name = "changed"
+	bundle.Warnings[0].Source = "changed"
+	if collected.SourceProvenance[0].Name != "hourly" || collected.SourceWarnings[0].Source != "discussion" {
+		t.Fatalf("collected source slices changed after bundle mutation: %#v %#v", collected.SourceProvenance, collected.SourceWarnings)
+	}
+}
+
+func TestBuildDerivedDailySlicesDaypartsAndAlerts(t *testing.T) {
+	location := testLocation()
+	resolved := resolveForTest(t, report.DailyToday, mustParse("2026-05-29T08:00:00-05:00"), location)
+	derived, err := BuildDerived(BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  location.String(),
+		Dayparts:  testDayparts(),
+		Collected: BuildCollected(testBundle(location)),
+	})
+	if err != nil {
+		t.Fatalf("BuildDerived() error = %v", err)
+	}
+
+	if len(derived.ValidPeriodHourlyPeriods) != 4 {
+		t.Fatalf("ValidPeriodHourlyPeriods length = %d, want 4", len(derived.ValidPeriodHourlyPeriods))
+	}
+	if len(derived.ValidPeriodNarrativePeriods) != 1 {
+		t.Fatalf("ValidPeriodNarrativePeriods length = %d, want 1", len(derived.ValidPeriodNarrativePeriods))
+	}
+	if len(derived.AlertOverlaps) != 1 || derived.AlertOverlaps[0].Event != "Flood Watch" {
+		t.Fatalf("AlertOverlaps = %#v, want Flood Watch overlap", derived.AlertOverlaps)
+	}
+	if len(derived.DailySummaries) != 1 || len(derived.DailySummaries[0].Dayparts) != 3 {
+		t.Fatalf("DailySummaries = %#v, want one summary with dayparts", derived.DailySummaries)
+	}
+	if len(derived.DaypartSummaries) != 3 {
+		t.Fatalf("DaypartSummaries length = %d, want 3", len(derived.DaypartSummaries))
+	}
+	if derived.PrecipTiming.FirstPrecipitation == nil || derived.PrecipTiming.FirstPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T08:00:00-05:00" {
+		t.Fatalf("PrecipTiming.FirstPrecipitation = %#v, want valid-period rain start", derived.PrecipTiming.FirstPrecipitation)
+	}
+	if derived.PrecipTiming.LastPrecipitation == nil || derived.PrecipTiming.LastPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T14:00:00-05:00" {
+		t.Fatalf("PrecipTiming.LastPrecipitation = %#v, want final closed window end", derived.PrecipTiming.LastPrecipitation)
+	}
+	if len(derived.PrecipTiming.PrecipitationWindows) != 2 {
+		t.Fatalf("PrecipitationWindows = %#v, want two threshold windows", derived.PrecipTiming.PrecipitationWindows)
+	}
+	if !derived.PrecipTiming.ThunderMentioned {
+		t.Fatal("PrecipTiming.ThunderMentioned = false, want true")
+	}
+	morning := derived.DailySummaries[0].Dayparts[0]
+	if len(morning.HourlyPeriods) != 1 || morning.MaxPrecipitationProbability == nil || morning.MaxPrecipitationProbability.Value != 60 {
+		t.Fatalf("morning summary = %#v, want sliced hour with precip max", morning)
+	}
+}
+
+func TestBuildDerivedOutlookBuildsPartialDaySummariesWithMissingOptionalSources(t *testing.T) {
+	location := testLocation()
+	resolved := resolveForTest(t, report.ThreeDay, mustParse("2026-05-29T08:00:00-05:00"), location)
+	bundle := testBundle(location)
+	bundle.Narrative = nil
+	bundle.Alerts = nil
+	bundle.Discussion = nil
+	bundle.WeatherStory = nil
+
+	derived, err := BuildDerived(BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  location.String(),
+		Dayparts:  testDayparts(),
+		Collected: BuildCollected(bundle),
+	})
+	if err != nil {
+		t.Fatalf("BuildDerived() error = %v", err)
+	}
+
+	if len(derived.DailySummaries) != 3 {
+		t.Fatalf("DailySummaries length = %d, want 3 partial-day summaries", len(derived.DailySummaries))
+	}
+	if len(derived.ValidPeriodNarrativePeriods) != 0 {
+		t.Fatalf("ValidPeriodNarrativePeriods length = %d, want 0 for missing optional source", len(derived.ValidPeriodNarrativePeriods))
+	}
+	if len(derived.AlertOverlaps) != 0 {
+		t.Fatalf("AlertOverlaps = %#v, want none for missing optional alerts", derived.AlertOverlaps)
+	}
+	if derived.DailySummaries[0].Period.Start.Format(time.RFC3339) != "2026-05-29T08:00:00-05:00" {
+		t.Fatalf("first summary start = %s, want valid-period start", derived.DailySummaries[0].Period.Start.Format(time.RFC3339))
+	}
+}
+
+func TestBuildDerivedWeekendAndTomorrow(t *testing.T) {
+	location := testLocation()
+	for _, id := range []report.ID{report.DailyTomorrow, report.Weekend} {
+		resolved := resolveForTest(t, id, mustParse("2026-05-29T08:00:00-05:00"), location)
+		derived, err := BuildDerived(BuildDerivedRequest{
+			Resolved:  resolved,
+			Timezone:  location.String(),
+			Dayparts:  testDayparts(),
+			Collected: BuildCollected(testBundle(location)),
+		})
+		if err != nil {
+			t.Fatalf("BuildDerived(%s) error = %v", id, err)
+		}
+		if len(derived.DailySummaries) == 0 {
+			t.Fatalf("BuildDerived(%s) DailySummaries length = 0, want summaries", id)
+		}
+	}
+}
+
+func TestBuildDerivedStormBuildsWindowSummary(t *testing.T) {
+	location := testLocation()
+	resolved := resolveStormForTest(t, location)
+	derived, err := BuildDerived(BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  location.String(),
+		Dayparts:  testDayparts(),
+		Collected: BuildCollected(testBundle(location)),
+	})
+	if err != nil {
+		t.Fatalf("BuildDerived() error = %v", err)
+	}
+
+	if len(derived.ValidPeriodHourlyPeriods) != 2 {
+		t.Fatalf("ValidPeriodHourlyPeriods length = %d, want 2 storm-window hours", len(derived.ValidPeriodHourlyPeriods))
+	}
+	if len(derived.ValidPeriodDailyPeriods) != 1 {
+		t.Fatalf("ValidPeriodDailyPeriods length = %d, want 1 daily period", len(derived.ValidPeriodDailyPeriods))
+	}
+	if derived.StormWindowSummary == nil {
+		t.Fatal("StormWindowSummary = nil, want summary")
+	}
+	if derived.StormWindowSummary.MaxPrecipitationProbability == nil || derived.StormWindowSummary.MaxPrecipitationProbability.Value != 80 {
+		t.Fatalf("StormWindowSummary = %#v, want peak precipitation", derived.StormWindowSummary)
+	}
+	if len(derived.StormWindowSummary.AlertOverlaps) != 1 {
+		t.Fatalf("StormWindowSummary.AlertOverlaps length = %d, want 1", len(derived.StormWindowSummary.AlertOverlaps))
+	}
+}
+
+func testBundle(location *time.Location) *weatherdata.Bundle {
+	return &weatherdata.Bundle{
+		FetchedAt: mustParse("2026-05-29T10:00:00Z"),
+		Current:   &weatherdata.Current{ConditionText: "Cloudy"},
+		Hourly: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+			hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Showers", 60, 10),
+			hour(location, "2026-05-29T12:00:00-05:00", "2026-05-29T13:00:00-05:00", "Thunderstorms", 80, 35),
+			hour(location, "2026-05-29T13:00:00-05:00", "2026-05-29T14:00:00-05:00", "Heavy rain", 70, 25),
+			hour(location, "2026-05-29T14:00:00-05:00", "2026-05-29T15:00:00-05:00", "Hot", 10, 15),
+			hour(location, "2026-05-30T09:00:00-05:00", "2026-05-30T10:00:00-05:00", "Clear", 0, 5),
+		}},
+		Narrative: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+			hour(location, "2026-05-29T06:00:00-05:00", "2026-05-29T18:00:00-05:00", "Storm chances peak midday.", 70, 20),
+		}},
+		Daily: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+			hour(location, "2026-05-29T00:00:00-05:00", "2026-05-30T00:00:00-05:00", "Storms", 70, 20),
+		}},
+		Alerts: &weatherdata.AlertRun{Alerts: []json.RawMessage{
+			json.RawMessage(`{"event":"Flood Watch","headline":"Flooding possible","severity":"Moderate","effective":"2026-05-29T11:00:00-05:00","expires":"2026-05-29T15:00:00-05:00"}`),
+		}},
+		Discussion:   &weatherdata.Discussion{Product: "discussion", KeyMessages: []string{"Storm confidence is moderate."}},
+		WeatherStory: &weatherdata.WeatherStory{Title: "Storm Risk"},
+		Sources:      []weatherdata.Source{{Name: "hourly"}},
+		Warnings:     []weatherdata.SourceWarning{{Source: "daily", Code: "missing_source"}},
+	}
+}
+
+func hour(location *time.Location, start string, end string, text string, precip float64, gust float64) weatherdata.ForecastPeriod {
+	temperature := 70.0
+	return weatherdata.ForecastPeriod{
+		StartTime:                         mustParse(start).In(location),
+		EndTime:                           mustParse(end).In(location),
+		TextDescription:                   text,
+		TemperatureF:                      &temperature,
+		ProbabilityOfPrecipitationPercent: &precip,
+		WindGustMph:                       &gust,
+	}
+}
+
+func testDayparts() []forecast.DaypartDefinition {
+	return []forecast.DaypartDefinition{
+		{Name: "morning", Start: "06:00", End: "12:00"},
+		{Name: "afternoon", Start: "12:00", End: "18:00"},
+		{Name: "evening", Start: "18:00", End: "24:00"},
+	}
+}
+
+func resolveForTest(t *testing.T, id report.ID, now time.Time, location *time.Location) report.Resolved {
+	t.Helper()
+	resolved, err := report.Resolve(id, report.ResolveRequest{Now: now, Location: location})
+	if err != nil {
+		t.Fatalf("resolve %s: %v", id, err)
+	}
+	return resolved
+}
+
+func resolveStormForTest(t *testing.T, location *time.Location) report.Resolved {
+	t.Helper()
+	resolved, err := report.Resolve(report.Storm, report.ResolveRequest{
+		Now:        mustParse("2026-05-29T08:00:00-05:00"),
+		Location:   location,
+		StormStart: mustParse("2026-05-29T11:30:00-05:00"),
+		StormEnd:   mustParse("2026-05-29T13:30:00-05:00"),
+	})
+	if err != nil {
+		t.Fatalf("resolve storm: %v", err)
+	}
+	return resolved
+}
+
+func testLocation() *time.Location {
+	location, err := time.LoadLocation("America/Chicago")
+	if err != nil {
+		panic(err)
+	}
+	return location
+}
+
+func mustParse(value string) time.Time {
+	parsed, err := time.Parse(time.RFC3339, value)
+	if err != nil {
+		panic(err)
+	}
+	return parsed
+}

internal/fileutil/fileutil.go

@@ -0,0 +1,48 @@
+// Package fileutil provides narrow filesystem helpers for durable artifacts.
+package fileutil
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+func WriteFileAtomic(path string, data []byte) error {
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+		return fmt.Errorf("create directory %q: %w", filepath.Dir(path), err)
+	}
+	tmp, err := os.CreateTemp(filepath.Dir(path), "."+filepath.Base(path)+".*.tmp")
+	if err != nil {
+		return fmt.Errorf("create temporary file for %q: %w", path, err)
+	}
+	tmpName := tmp.Name()
+	defer os.Remove(tmpName)
+	if _, err := tmp.Write(data); err != nil {
+		tmp.Close()
+		return fmt.Errorf("write temporary file for %q: %w", path, err)
+	}
+	if err := tmp.Close(); err != nil {
+		return fmt.Errorf("close temporary file for %q: %w", path, err)
+	}
+	if err := os.Rename(tmpName, path); err != nil {
+		return fmt.Errorf("save %q: %w", path, err)
+	}
+	return nil
+}
+
+func WriteJSONAtomic(path string, value any) error {
+	data, err := json.MarshalIndent(value, "", "  ")
+	if err != nil {
+		return fmt.Errorf("marshal %q: %w", path, err)
+	}
+	return WriteFileAtomic(path, data)
+}
+
+func CopyFileAtomic(source string, target string) error {
+	data, err := os.ReadFile(source)
+	if err != nil {
+		return fmt.Errorf("read %q: %w", source, err)
+	}
+	return WriteFileAtomic(target, data)
+}

internal/fileutil/fileutil_test.go

@@ -0,0 +1,103 @@
+package fileutil
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestWriteFileAtomicCreatesParentDirectory(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "nested", "artifact.txt")
+
+	if err := WriteFileAtomic(path, []byte("artifact")); err != nil {
+		t.Fatalf("WriteFileAtomic() error = %v", err)
+	}
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("ReadFile() error = %v", err)
+	}
+	if string(data) != "artifact" {
+		t.Fatalf("data = %q, want artifact", data)
+	}
+}
+
+func TestWriteFileAtomicOverwritesTarget(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "artifact.txt")
+	if err := WriteFileAtomic(path, []byte("old")); err != nil {
+		t.Fatalf("WriteFileAtomic() initial error = %v", err)
+	}
+
+	if err := WriteFileAtomic(path, []byte("new")); err != nil {
+		t.Fatalf("WriteFileAtomic() overwrite error = %v", err)
+	}
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("ReadFile() error = %v", err)
+	}
+	if string(data) != "new" {
+		t.Fatalf("data = %q, want new", data)
+	}
+}
+
+func TestWriteFileAtomicCleansTemporaryFileAfterRenameError(t *testing.T) {
+	dir := t.TempDir()
+	target := filepath.Join(dir, "target")
+	if err := os.Mkdir(target, 0o755); err != nil {
+		t.Fatalf("Mkdir() error = %v", err)
+	}
+
+	err := WriteFileAtomic(target, []byte("data"))
+	if err == nil {
+		t.Fatal("WriteFileAtomic() error = nil, want rename error")
+	}
+	if !strings.Contains(err.Error(), "save") {
+		t.Fatalf("error = %q, want save context", err.Error())
+	}
+	matches, err := filepath.Glob(filepath.Join(dir, ".target.*.tmp"))
+	if err != nil {
+		t.Fatalf("Glob() error = %v", err)
+	}
+	if len(matches) != 0 {
+		t.Fatalf("temporary files = %v, want none", matches)
+	}
+}
+
+func TestWriteJSONAtomic(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "artifact.json")
+
+	if err := WriteJSONAtomic(path, map[string]string{"status": "ok"}); err != nil {
+		t.Fatalf("WriteJSONAtomic() error = %v", err)
+	}
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("ReadFile() error = %v", err)
+	}
+	if string(data) != "{\n  \"status\": \"ok\"\n}" {
+		t.Fatalf("json = %q, want indented object", data)
+	}
+}
+
+func TestCopyFileAtomic(t *testing.T) {
+	dir := t.TempDir()
+	source := filepath.Join(dir, "source.txt")
+	target := filepath.Join(dir, "nested", "target.txt")
+	if err := os.WriteFile(source, []byte("copied"), 0o600); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
+	}
+
+	if err := CopyFileAtomic(source, target); err != nil {
+		t.Fatalf("CopyFileAtomic() error = %v", err)
+	}
+
+	data, err := os.ReadFile(target)
+	if err != nil {
+		t.Fatalf("ReadFile() error = %v", err)
+	}
+	if string(data) != "copied" {
+		t.Fatalf("data = %q, want copied", data)
+	}
+}

internal/forecast/dayparts.go

@@ -0,0 +1,54 @@
+package forecast
+
+import (
+	"fmt"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type DaypartDefinition struct {
+	Name  string `json:"name"`
+	Start string `json:"start"`
+	End   string `json:"end"`
+}
+
+type DaypartWindow struct {
+	Name   string          `json:"name"`
+	Start  time.Time       `json:"start"`
+	End    time.Time       `json:"end"`
+	Period timeutil.Period `json:"period"`
+}
+
+func ResolveDayparts(date time.Time, location *time.Location, definitions []DaypartDefinition) ([]DaypartWindow, error) {
+	if len(definitions) == 0 {
+		return nil, fmt.Errorf("daypart definitions are required")
+	}
+	windows := make([]DaypartWindow, 0, len(definitions))
+	for i, def := range definitions {
+		if def.Name == "" {
+			return nil, fmt.Errorf("daypart[%d].name is required", i)
+		}
+		startClock, err := timeutil.ParseClock(def.Start)
+		if err != nil {
+			return nil, fmt.Errorf("daypart[%d].start: %w", i, err)
+		}
+		endClock, err := timeutil.ParseClock(def.End)
+		if err != nil {
+			return nil, fmt.Errorf("daypart[%d].end: %w", i, err)
+		}
+		period := timeutil.ClockWindow(date, location, startClock, endClock)
+		windows = append(windows, DaypartWindow{
+			Name:   def.Name,
+			Start:  period.Start,
+			End:    period.End,
+			Period: period,
+		})
+	}
+	return windows, nil
+}
+
+func PeriodForForecastPeriod(period weatherdata.ForecastPeriod) timeutil.Period {
+	return timeutil.Period{Start: period.StartTime, End: period.EndTime}
+}

internal/forecast/derive.go

@@ -0,0 +1,543 @@
+package forecast
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+type DailySummary struct {
+	Date             string                       `json:"date"`
+	Period           timeutil.Period              `json:"period"`
+	Dayparts         []DaypartSummary             `json:"dayparts"`
+	NarrativePeriods []weatherdata.ForecastPeriod `json:"narrativePeriods,omitempty"`
+	AlertOverlaps    []AlertOverlap               `json:"alertOverlaps,omitempty"`
+	Discussion       *weatherdata.Discussion      `json:"discussion,omitempty"`
+	SourceWarnings   []weatherdata.SourceWarning  `json:"sourceWarnings,omitempty"`
+	SourceProvenance []weatherdata.Source         `json:"sourceProvenance,omitempty"`
+}
+
+type DaypartSummary struct {
+	Name                        string                       `json:"name"`
+	Period                      timeutil.Period              `json:"period"`
+	HourlyPeriods               []weatherdata.ForecastPeriod `json:"hourlyPeriods"`
+	Temperature                 Range                        `json:"temperature,omitempty"`
+	ApparentTemperature         Range                        `json:"apparentTemperature,omitempty"`
+	MaxPrecipitationProbability *TimedValue                  `json:"maxPrecipitationProbability,omitempty"`
+	PeakWindSpeed               *TimedValue                  `json:"peakWindSpeed,omitempty"`
+	PeakWindGust                *TimedValue                  `json:"peakWindGust,omitempty"`
+	DominantCondition           string                       `json:"dominantCondition,omitempty"`
+	NotableConditions           []string                     `json:"notableConditions,omitempty"`
+	Indicators                  Indicators                   `json:"indicators"`
+	AlertOverlaps               []AlertOverlap               `json:"alertOverlaps,omitempty"`
+}
+
+type Range struct {
+	Min *float64 `json:"min,omitempty"`
+	Max *float64 `json:"max,omitempty"`
+}
+
+type TimedValue struct {
+	Value float64   `json:"value"`
+	Time  time.Time `json:"time"`
+}
+
+const DefaultPrecipWindowProbabilityThreshold = 40
+
+type Indicators struct {
+	Snow bool `json:"snow,omitempty"`
+	Ice  bool `json:"ice,omitempty"`
+	Fog  bool `json:"fog,omitempty"`
+	Heat bool `json:"heat,omitempty"`
+	Cold bool `json:"cold,omitempty"`
+	Wind bool `json:"wind,omitempty"`
+}
+
+type AlertOverlap struct {
+	Event       string          `json:"event,omitempty"`
+	Headline    string          `json:"headline,omitempty"`
+	Severity    string          `json:"severity,omitempty"`
+	Period      timeutil.Period `json:"period"`
+	Overlap     timeutil.Period `json:"overlap"`
+	Description string          `json:"description,omitempty"`
+}
+
+type PrecipTiming struct {
+	MaxPrecipitationProbability *TimedValue           `json:"maxPrecipitationProbability,omitempty"`
+	FirstPrecipitation          *TimedValue           `json:"firstPrecipitation,omitempty"`
+	LastPrecipitation           *TimedValue           `json:"lastPrecipitation,omitempty"`
+	ProbabilityThreshold        float64               `json:"probabilityThreshold"`
+	PrecipitationWindows        []PrecipitationWindow `json:"precipitationWindows,omitempty"`
+	ThunderMentioned            bool                  `json:"thunderMentioned,omitempty"`
+}
+
+type PrecipitationWindow struct {
+	Start                       time.Time  `json:"start"`
+	End                         *time.Time `json:"end,omitempty"`
+	MaxPrecipitationProbability TimedValue `json:"maxPrecipitationProbability"`
+	ProbabilityThreshold        float64    `json:"probabilityThreshold"`
+}
+
+func BuildPrecipTiming(periods []weatherdata.ForecastPeriod) PrecipTiming {
+	return buildPrecipTimingWithThreshold(periods, DefaultPrecipWindowProbabilityThreshold)
+}
+
+func buildPrecipTimingWithThreshold(periods []weatherdata.ForecastPeriod, threshold float64) PrecipTiming {
+	timing := PrecipTiming{ProbabilityThreshold: threshold}
+	sorted := append([]weatherdata.ForecastPeriod(nil), periods...)
+	sort.SliceStable(sorted, func(i int, j int) bool {
+		return sorted[i].StartTime.Before(sorted[j].StartTime)
+	})
+
+	var active *PrecipitationWindow
+	var activeLastEnd time.Time
+	closeActive := func() {
+		if active == nil {
+			return
+		}
+		end := activeLastEnd
+		active.End = &end
+		timing.PrecipitationWindows = append(timing.PrecipitationWindows, *active)
+		active = nil
+	}
+	startActive := func(forecastPeriod weatherdata.ForecastPeriod, probability float64) {
+		active = &PrecipitationWindow{
+			Start: forecastPeriod.StartTime,
+			MaxPrecipitationProbability: TimedValue{
+				Value: probability,
+				Time:  forecastPeriod.StartTime,
+			},
+			ProbabilityThreshold: threshold,
+		}
+		activeLastEnd = forecastPeriod.EndTime
+		if timing.FirstPrecipitation == nil {
+			timing.FirstPrecipitation = &TimedValue{
+				Value: probability,
+				Time:  forecastPeriod.StartTime,
+			}
+		}
+	}
+
+	for _, forecastPeriod := range sorted {
+		setMaxTimedValue(&timing.MaxPrecipitationProbability, forecastPeriod.ProbabilityOfPrecipitationPercent, forecastPeriod.StartTime)
+		if forecastPeriod.ProbabilityOfPrecipitationPercent == nil || *forecastPeriod.ProbabilityOfPrecipitationPercent < threshold {
+			closeActive()
+		} else {
+			probability := *forecastPeriod.ProbabilityOfPrecipitationPercent
+			if active == nil {
+				startActive(forecastPeriod, probability)
+			} else {
+				if forecastPeriod.StartTime.After(activeLastEnd) {
+					closeActive()
+					startActive(forecastPeriod, probability)
+				}
+				if probability > active.MaxPrecipitationProbability.Value {
+					active.MaxPrecipitationProbability = TimedValue{
+						Value: probability,
+						Time:  forecastPeriod.StartTime,
+					}
+				}
+				if forecastPeriod.EndTime.After(activeLastEnd) {
+					activeLastEnd = forecastPeriod.EndTime
+				}
+			}
+		}
+		if mentionsThunder(forecastPeriod.TextDescription) {
+			timing.ThunderMentioned = true
+		}
+	}
+	if active != nil {
+		timing.PrecipitationWindows = append(timing.PrecipitationWindows, *active)
+	}
+	if len(timing.PrecipitationWindows) > 0 {
+		final := timing.PrecipitationWindows[len(timing.PrecipitationWindows)-1]
+		if final.End != nil {
+			timing.LastPrecipitation = &TimedValue{
+				Value: final.MaxPrecipitationProbability.Value,
+				Time:  *final.End,
+			}
+		}
+	}
+	return timing
+}
+
+func BuildDailySummary(bundle *weatherdata.Bundle, date time.Time, location *time.Location, dayparts []DaypartDefinition) (*DailySummary, error) {
+	if bundle == nil {
+		return nil, fmt.Errorf("forecast bundle is required")
+	}
+	if location == nil {
+		location = time.UTC
+	}
+	if bundle.Hourly == nil || len(bundle.Hourly.Periods) == 0 {
+		return nil, fmt.Errorf("hourly forecast data is required")
+	}
+	day := timeutil.CivilDay(date, location)
+	windows, err := ResolveDayparts(date, location, dayparts)
+	if err != nil {
+		return nil, err
+	}
+	alerts := AlertOverlaps(bundle.Alerts, day)
+
+	summary := &DailySummary{
+		Date:             day.Start.Format(timeutil.DateLayout),
+		Period:           day,
+		NarrativePeriods: SelectNarrativePeriods(bundle, day),
+		AlertOverlaps:    alerts,
+		Discussion:       SelectDiscussion(bundle),
+		SourceWarnings:   bundle.Warnings,
+		SourceProvenance: bundle.Sources,
+	}
+	for _, window := range windows {
+		periods := SelectHourlyPeriods(bundle.Hourly, window.Period)
+		daypartSummary := SummarizeDaypart(window.Name, window.Period, periods)
+		daypartSummary.AlertOverlaps = overlapsWithin(alerts, window.Period)
+		summary.Dayparts = append(summary.Dayparts, daypartSummary)
+	}
+	return summary, nil
+}
+
+func BuildPeriodDailySummaries(bundle *weatherdata.Bundle, period timeutil.Period, location *time.Location, dayparts []DaypartDefinition) ([]DailySummary, error) {
+	if !period.IsValid() {
+		return nil, fmt.Errorf("valid forecast period is required")
+	}
+	if location == nil {
+		location = time.UTC
+	}
+	var summaries []DailySummary
+	for day := timeutil.CivilDay(period.Start, location); day.Start.Before(period.End); day = timeutil.CivilDay(day.Start.AddDate(0, 0, 1), location) {
+		overlap, ok := day.Intersection(period)
+		if !ok {
+			continue
+		}
+		summary, err := buildDailySummaryForPeriod(bundle, overlap, location, dayparts)
+		if err != nil {
+			return nil, err
+		}
+		summaries = append(summaries, *summary)
+	}
+	return summaries, nil
+}
+
+func buildDailySummaryForPeriod(bundle *weatherdata.Bundle, period timeutil.Period, location *time.Location, dayparts []DaypartDefinition) (*DailySummary, error) {
+	if bundle == nil {
+		return nil, fmt.Errorf("forecast bundle is required")
+	}
+	if bundle.Hourly == nil || len(bundle.Hourly.Periods) == 0 {
+		return nil, fmt.Errorf("hourly forecast data is required")
+	}
+	windows, err := ResolveDayparts(period.Start, location, dayparts)
+	if err != nil {
+		return nil, err
+	}
+	alerts := AlertOverlaps(bundle.Alerts, period)
+	summary := &DailySummary{
+		Date:             period.Start.In(location).Format(timeutil.DateLayout),
+		Period:           period,
+		NarrativePeriods: SelectNarrativePeriods(bundle, period),
+		AlertOverlaps:    alerts,
+		Discussion:       SelectDiscussion(bundle),
+		SourceWarnings:   bundle.Warnings,
+		SourceProvenance: bundle.Sources,
+	}
+	for _, window := range windows {
+		clipped, ok := window.Period.Intersection(period)
+		if !ok {
+			continue
+		}
+		periods := SelectHourlyPeriods(bundle.Hourly, clipped)
+		daypartSummary := SummarizeDaypart(window.Name, clipped, periods)
+		daypartSummary.AlertOverlaps = overlapsWithin(alerts, clipped)
+		summary.Dayparts = append(summary.Dayparts, daypartSummary)
+	}
+	return summary, nil
+}
+
+func SelectHourlyPeriods(run *weatherdata.ForecastRun, period timeutil.Period) []weatherdata.ForecastPeriod {
+	if run == nil {
+		return nil
+	}
+	var selected []weatherdata.ForecastPeriod
+	for _, forecastPeriod := range run.Periods {
+		if PeriodForForecastPeriod(forecastPeriod).Overlaps(period) {
+			selected = append(selected, forecastPeriod)
+		}
+	}
+	sort.SliceStable(selected, func(i int, j int) bool {
+		return selected[i].StartTime.Before(selected[j].StartTime)
+	})
+	return selected
+}
+
+func SelectNarrativePeriods(bundle *weatherdata.Bundle, period timeutil.Period) []weatherdata.ForecastPeriod {
+	if bundle == nil || bundle.Narrative == nil {
+		return nil
+	}
+	return SelectHourlyPeriods(bundle.Narrative, period)
+}
+
+func SelectDiscussion(bundle *weatherdata.Bundle) *weatherdata.Discussion {
+	if bundle == nil {
+		return nil
+	}
+	return bundle.Discussion
+}
+
+func SummarizeDaypart(name string, period timeutil.Period, periods []weatherdata.ForecastPeriod) DaypartSummary {
+	summary := DaypartSummary{
+		Name:          name,
+		Period:        period,
+		HourlyPeriods: periods,
+	}
+	conditionCounts := map[string]int{}
+	conditions := map[string]struct{}{}
+
+	for _, forecastPeriod := range periods {
+		addRangeValue(&summary.Temperature, periodTemperatureValues(forecastPeriod)...)
+		addRangeValue(&summary.ApparentTemperature, valueFromPointers(forecastPeriod.ApparentTemperatureF, forecastPeriod.ApparentTemperatureC)...)
+		setMaxTimedValue(&summary.MaxPrecipitationProbability, forecastPeriod.ProbabilityOfPrecipitationPercent, forecastPeriod.StartTime)
+		setMaxTimedValue(&summary.PeakWindSpeed, firstValue(forecastPeriod.WindSpeedMph, forecastPeriod.WindSpeedKmh), forecastPeriod.StartTime)
+		setMaxTimedValue(&summary.PeakWindGust, firstValue(forecastPeriod.WindGustMph, forecastPeriod.WindGustKmh), forecastPeriod.StartTime)
+
+		text := strings.TrimSpace(forecastPeriod.TextDescription)
+		if text != "" {
+			conditionCounts[text]++
+			conditions[text] = struct{}{}
+			summary.Indicators = mergeIndicators(summary.Indicators, indicatorsForText(text))
+		}
+		summary.Indicators = mergeIndicators(summary.Indicators, numericIndicators(forecastPeriod))
+	}
+
+	summary.DominantCondition = dominantCondition(conditionCounts)
+	summary.NotableConditions = sortedKeys(conditions)
+	return summary
+}
+
+func periodTemperatureValues(period weatherdata.ForecastPeriod) []*float64 {
+	values := []*float64{}
+	values = append(values, valueFromPointers(period.TemperatureF, period.TemperatureC)...)
+	values = append(values, valueFromPointers(period.TemperatureFMin, period.TemperatureCMin)...)
+	values = append(values, valueFromPointers(period.TemperatureFMax, period.TemperatureCMax)...)
+	return values
+}
+
+func valueFromPointers(values ...*float64) []*float64 {
+	for _, value := range values {
+		if value != nil {
+			return []*float64{value}
+		}
+	}
+	return nil
+}
+
+func firstValue(values ...*float64) *float64 {
+	for _, value := range values {
+		if value != nil {
+			return value
+		}
+	}
+	return nil
+}
+
+func addRangeValue(target *Range, values ...*float64) {
+	for _, value := range values {
+		if value == nil {
+			continue
+		}
+		if target.Min == nil || *value < *target.Min {
+			copied := *value
+			target.Min = &copied
+		}
+		if target.Max == nil || *value > *target.Max {
+			copied := *value
+			target.Max = &copied
+		}
+	}
+}
+
+func setMaxTimedValue(target **TimedValue, value *float64, at time.Time) {
+	if value == nil {
+		return
+	}
+	if *target == nil || value != nil && *value > (*target).Value {
+		*target = &TimedValue{Value: *value, Time: at}
+	}
+}
+
+func dominantCondition(counts map[string]int) string {
+	var dominant string
+	var dominantCount int
+	for condition, count := range counts {
+		if count > dominantCount || count == dominantCount && condition < dominant {
+			dominant = condition
+			dominantCount = count
+		}
+	}
+	return dominant
+}
+
+func sortedKeys(values map[string]struct{}) []string {
+	out := make([]string, 0, len(values))
+	for value := range values {
+		out = append(out, value)
+	}
+	sort.Strings(out)
+	return out
+}
+
+func indicatorsForText(text string) Indicators {
+	lower := strings.ToLower(text)
+	return Indicators{
+		Snow: strings.Contains(lower, "snow"),
+		Ice:  strings.Contains(lower, "ice") || strings.Contains(lower, "freezing") || strings.Contains(lower, "sleet"),
+		Fog:  strings.Contains(lower, "fog"),
+		Wind: strings.Contains(lower, "wind") || strings.Contains(lower, "gust"),
+	}
+}
+
+func mentionsThunder(text string) bool {
+	return strings.Contains(strings.ToLower(text), "thunder")
+}
+
+func numericIndicators(period weatherdata.ForecastPeriod) Indicators {
+	windGust := firstValue(period.WindGustMph, period.WindGustKmh)
+	windSpeed := firstValue(period.WindSpeedMph, period.WindSpeedKmh)
+	indicators := Indicators{}
+	if period.TemperatureF != nil {
+		indicators.Heat = *period.TemperatureF >= 95
+		indicators.Cold = *period.TemperatureF <= 32
+	} else if period.TemperatureC != nil {
+		indicators.Heat = *period.TemperatureC >= 35
+		indicators.Cold = *period.TemperatureC <= 0
+	}
+	if windGust != nil && *windGust >= 35 || windSpeed != nil && *windSpeed >= 25 {
+		indicators.Wind = true
+	}
+	return indicators
+}
+
+func mergeIndicators(left Indicators, right Indicators) Indicators {
+	return Indicators{
+		Snow: left.Snow || right.Snow,
+		Ice:  left.Ice || right.Ice,
+		Fog:  left.Fog || right.Fog,
+		Heat: left.Heat || right.Heat,
+		Cold: left.Cold || right.Cold,
+		Wind: left.Wind || right.Wind,
+	}
+}
+
+func AlertOverlaps(alertRun *weatherdata.AlertRun, period timeutil.Period) []AlertOverlap {
+	if alertRun == nil {
+		return nil
+	}
+	var overlaps []AlertOverlap
+	for _, rawAlert := range alertRun.Alerts {
+		alert, ok := parseAlert(rawAlert)
+		if !ok || !alert.Period.IsValid() || !alert.Period.Overlaps(period) {
+			continue
+		}
+		overlaps = append(overlaps, AlertOverlap{
+			Event:       alert.Event,
+			Headline:    alert.Headline,
+			Severity:    alert.Severity,
+			Period:      alert.Period,
+			Overlap:     intersect(alert.Period, period),
+			Description: alert.Description,
+		})
+	}
+	sort.SliceStable(overlaps, func(i int, j int) bool {
+		return overlaps[i].Period.Start.Before(overlaps[j].Period.Start)
+	})
+	return overlaps
+}
+
+type parsedAlert struct {
+	Event       string
+	Headline    string
+	Severity    string
+	Description string
+	Period      timeutil.Period
+}
+
+func parseAlert(raw json.RawMessage) (parsedAlert, bool) {
+	var fields map[string]json.RawMessage
+	if err := json.Unmarshal(raw, &fields); err != nil {
+		return parsedAlert{}, false
+	}
+	alert := parsedAlert{
+		Event:       stringField(fields, "event"),
+		Headline:    firstStringField(fields, "headline", "title"),
+		Severity:    stringField(fields, "severity"),
+		Description: firstStringField(fields, "description", "instruction"),
+	}
+	start, startOK := firstTimeField(fields, "effective", "onset", "startsAt", "startTime", "sent")
+	end, endOK := firstTimeField(fields, "expires", "ends", "endsAt", "endTime")
+	if !startOK || !endOK {
+		return parsedAlert{}, false
+	}
+	alert.Period = timeutil.Period{Start: start, End: end}
+	return alert, true
+}
+
+func stringField(fields map[string]json.RawMessage, name string) string {
+	value, ok := fields[name]
+	if !ok {
+		return ""
+	}
+	var out string
+	if err := json.Unmarshal(value, &out); err != nil {
+		return ""
+	}
+	return out
+}
+
+func firstStringField(fields map[string]json.RawMessage, names ...string) string {
+	for _, name := range names {
+		if value := stringField(fields, name); value != "" {
+			return value
+		}
+	}
+	return ""
+}
+
+func firstTimeField(fields map[string]json.RawMessage, names ...string) (time.Time, bool) {
+	for _, name := range names {
+		value := stringField(fields, name)
+		if value == "" {
+			continue
+		}
+		parsed, err := time.Parse(time.RFC3339, value)
+		if err == nil {
+			return parsed, true
+		}
+	}
+	return time.Time{}, false
+}
+
+func intersect(left timeutil.Period, right timeutil.Period) timeutil.Period {
+	start := left.Start
+	if right.Start.After(start) {
+		start = right.Start
+	}
+	end := left.End
+	if right.End.Before(end) {
+		end = right.End
+	}
+	return timeutil.Period{Start: start, End: end}
+}
+
+func overlapsWithin(alerts []AlertOverlap, period timeutil.Period) []AlertOverlap {
+	var out []AlertOverlap
+	for _, alert := range alerts {
+		if alert.Period.Overlaps(period) {
+			alert.Overlap = intersect(alert.Period, period)
+			out = append(out, alert)
+		}
+	}
+	return out
+}

internal/forecast/derive_test.go

@@ -0,0 +1,388 @@
+package forecast
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+)
+
+func TestBuildDailySummaryGroupsDaypartsAndComputesMetrics(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	bundle := testBundle(location)
+	date := time.Date(2026, 5, 29, 12, 0, 0, 0, location)
+	dayparts := []DaypartDefinition{
+		{Name: "overnight", Start: "00:00", End: "06:00"},
+		{Name: "morning", Start: "06:00", End: "12:00"},
+		{Name: "afternoon", Start: "12:00", End: "18:00"},
+		{Name: "evening", Start: "18:00", End: "24:00"},
+	}
+
+	summary, err := BuildDailySummary(bundle, date, location, dayparts)
+	if err != nil {
+		t.Fatalf("BuildDailySummary() error = %v", err)
+	}
+
+	if len(summary.Dayparts) != 4 {
+		t.Fatalf("Dayparts length = %d, want 4", len(summary.Dayparts))
+	}
+	morning := summary.Dayparts[1]
+	if len(morning.HourlyPeriods) != 2 {
+		t.Fatalf("morning periods = %d, want 2", len(morning.HourlyPeriods))
+	}
+	assertRange(t, "morning temperature", morning.Temperature, 58, 72)
+	if morning.MaxPrecipitationProbability == nil || morning.MaxPrecipitationProbability.Value != 70 {
+		t.Fatalf("morning max precip = %#v, want 70", morning.MaxPrecipitationProbability)
+	}
+	if morning.PeakWindGust == nil || morning.PeakWindGust.Value != 40 {
+		t.Fatalf("morning peak gust = %#v, want 40", morning.PeakWindGust)
+	}
+	if morning.DominantCondition != "Thunderstorms and gusty wind" {
+		t.Fatalf("morning dominant = %q, want raw forecast condition", morning.DominantCondition)
+	}
+	if !morning.Indicators.Wind {
+		t.Fatalf("morning indicators = %#v, want wind", morning.Indicators)
+	}
+
+	afternoon := summary.Dayparts[2]
+	assertRange(t, "afternoon apparent", afternoon.ApparentTemperature, 100, 100)
+	if !afternoon.Indicators.Heat {
+		t.Fatalf("afternoon indicators = %#v, want heat", afternoon.Indicators)
+	}
+	if len(summary.NarrativePeriods) != 1 {
+		t.Fatalf("NarrativePeriods length = %d, want 1", len(summary.NarrativePeriods))
+	}
+	if len(summary.AlertOverlaps) != 1 {
+		t.Fatalf("AlertOverlaps length = %d, want 1", len(summary.AlertOverlaps))
+	}
+	if len(morning.AlertOverlaps) != 1 {
+		t.Fatalf("morning AlertOverlaps length = %d, want 1", len(morning.AlertOverlaps))
+	}
+
+	if _, err := json.Marshal(summary.Dayparts); err != nil {
+		t.Fatalf("daypart summaries are not JSON inspectable: %v", err)
+	}
+}
+
+func TestBuildDailySummaryFromFixtureBundle(t *testing.T) {
+	data, err := os.ReadFile(filepath.Join("testdata", "daily_bundle.json"))
+	if err != nil {
+		t.Fatalf("read fixture bundle: %v", err)
+	}
+	var bundle weatherdata.Bundle
+	if err := json.Unmarshal(data, &bundle); err != nil {
+		t.Fatalf("decode fixture bundle: %v", err)
+	}
+	location := time.FixedZone("Test", -5*60*60)
+	summary, err := BuildDailySummary(&bundle, mustParse("2026-05-29T12:00:00-05:00"), location, []DaypartDefinition{
+		{Name: "morning", Start: "06:00", End: "12:00"},
+		{Name: "afternoon", Start: "12:00", End: "18:00"},
+	})
+	if err != nil {
+		t.Fatalf("BuildDailySummary() error = %v", err)
+	}
+	if len(summary.Dayparts) != 2 {
+		t.Fatalf("Dayparts length = %d, want 2", len(summary.Dayparts))
+	}
+	if summary.Dayparts[0].DominantCondition != "Showers and thunderstorms" {
+		t.Fatalf("morning dominant = %q, want raw forecast condition", summary.Dayparts[0].DominantCondition)
+	}
+	if len(summary.AlertOverlaps) != 1 {
+		t.Fatalf("AlertOverlaps length = %d, want 1", len(summary.AlertOverlaps))
+	}
+}
+
+func TestOvernightGroupingAcrossMidnight(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	date := time.Date(2026, 5, 29, 12, 0, 0, 0, location)
+	bundle := &weatherdata.Bundle{Hourly: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T23:00:00-05:00", "2026-05-30T00:00:00-05:00", "Snow", 31, nil, nil, nil, nil),
+		hour(location, "2026-05-30T05:00:00-05:00", "2026-05-30T06:00:00-05:00", "Fog", 30, nil, nil, nil, nil),
+		hour(location, "2026-05-30T06:00:00-05:00", "2026-05-30T07:00:00-05:00", "Clear", 35, nil, nil, nil, nil),
+	}}}
+
+	summary, err := BuildDailySummary(bundle, date, location, []DaypartDefinition{
+		{Name: "night", Start: "22:00", End: "06:00"},
+	})
+	if err != nil {
+		t.Fatalf("BuildDailySummary() error = %v", err)
+	}
+	night := summary.Dayparts[0]
+	if len(night.HourlyPeriods) != 2 {
+		t.Fatalf("night periods = %d, want 2", len(night.HourlyPeriods))
+	}
+	if !night.Indicators.Snow || !night.Indicators.Fog || !night.Indicators.Cold {
+		t.Fatalf("night indicators = %#v, want snow, fog, and cold", night.Indicators)
+	}
+}
+
+func TestBoundaryTimestampsAtDaypartEdges(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	date := time.Date(2026, 5, 29, 12, 0, 0, 0, location)
+	bundle := &weatherdata.Bundle{Hourly: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T05:00:00-05:00", "2026-05-29T06:00:00-05:00", "Before", 55, nil, nil, nil, nil),
+		hour(location, "2026-05-29T06:00:00-05:00", "2026-05-29T07:00:00-05:00", "Start", 56, nil, nil, nil, nil),
+		hour(location, "2026-05-29T12:00:00-05:00", "2026-05-29T13:00:00-05:00", "After", 70, nil, nil, nil, nil),
+	}}}
+
+	summary, err := BuildDailySummary(bundle, date, location, []DaypartDefinition{
+		{Name: "morning", Start: "06:00", End: "12:00"},
+	})
+	if err != nil {
+		t.Fatalf("BuildDailySummary() error = %v", err)
+	}
+	morning := summary.Dayparts[0]
+	if len(morning.HourlyPeriods) != 1 {
+		t.Fatalf("morning periods = %d, want only start-boundary period", len(morning.HourlyPeriods))
+	}
+	if morning.HourlyPeriods[0].TextDescription != "Start" {
+		t.Fatalf("selected period = %q, want Start", morning.HourlyPeriods[0].TextDescription)
+	}
+}
+
+func TestBuildDailySummaryRequiresHourlyData(t *testing.T) {
+	location := time.UTC
+	_, err := BuildDailySummary(&weatherdata.Bundle{}, time.Now(), location, []DaypartDefinition{
+		{Name: "morning", Start: "06:00", End: "12:00"},
+	})
+	if err == nil {
+		t.Fatal("BuildDailySummary() error = nil, want missing hourly error")
+	}
+}
+
+func TestBuildPeriodDailySummariesClipsPartialDays(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	bundle := &weatherdata.Bundle{Hourly: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T05:00:00-05:00", "2026-05-29T06:00:00-05:00", "Before", 50, nil, nil, nil, nil),
+		hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Showers", 60, nil, ptr(60), nil, nil),
+		hour(location, "2026-05-30T14:00:00-05:00", "2026-05-30T15:00:00-05:00", "Hot", 95, nil, nil, nil, nil),
+		hour(location, "2026-05-31T20:00:00-05:00", "2026-05-31T21:00:00-05:00", "Wind", 70, nil, nil, nil, ptr(35)),
+	}}}
+	period := timeutil.Period{
+		Start: mustParse("2026-05-29T07:00:00-05:00").In(location),
+		End:   mustParse("2026-06-01T00:00:00-05:00").In(location),
+	}
+
+	summaries, err := BuildPeriodDailySummaries(bundle, period, location, []DaypartDefinition{
+		{Name: "morning", Start: "06:00", End: "12:00"},
+		{Name: "afternoon", Start: "12:00", End: "18:00"},
+		{Name: "evening", Start: "18:00", End: "24:00"},
+	})
+	if err != nil {
+		t.Fatalf("BuildPeriodDailySummaries() error = %v", err)
+	}
+	if len(summaries) != 3 {
+		t.Fatalf("summaries length = %d, want 3", len(summaries))
+	}
+	if summaries[0].Period.Start.Format(time.RFC3339) != "2026-05-29T07:00:00-05:00" {
+		t.Fatalf("first period start = %s, want clipped start", summaries[0].Period.Start.Format(time.RFC3339))
+	}
+	if len(summaries[0].Dayparts[0].HourlyPeriods) != 1 || summaries[0].Dayparts[0].HourlyPeriods[0].TextDescription != "Showers" {
+		t.Fatalf("first morning periods = %#v, want only post-start hour", summaries[0].Dayparts[0].HourlyPeriods)
+	}
+	if summaries[2].Dayparts[2].PeakWindGust == nil || summaries[2].Dayparts[2].PeakWindGust.Value != 35 {
+		t.Fatalf("third evening gust = %#v, want 35", summaries[2].Dayparts[2].PeakWindGust)
+	}
+}
+
+func TestAlertOverlap(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	raw := json.RawMessage(`{"event":"Flood Watch","headline":"Flooding possible","severity":"Moderate","effective":"2026-05-29T07:00:00-05:00","expires":"2026-05-29T10:00:00-05:00"}`)
+	alertRun := &weatherdata.AlertRun{Alerts: []json.RawMessage{raw}}
+	period := timeutil.Period{
+		Start: mustParse("2026-05-29T06:00:00-05:00").In(location),
+		End:   mustParse("2026-05-29T09:00:00-05:00").In(location),
+	}
+
+	overlaps := AlertOverlaps(alertRun, period)
+	if len(overlaps) != 1 {
+		t.Fatalf("overlaps length = %d, want 1", len(overlaps))
+	}
+	if overlaps[0].Overlap.Start.Format(time.RFC3339) != "2026-05-29T07:00:00-05:00" {
+		t.Fatalf("overlap start = %s, want alert start", overlaps[0].Overlap.Start.Format(time.RFC3339))
+	}
+	if overlaps[0].Overlap.End.Format(time.RFC3339) != "2026-05-29T09:00:00-05:00" {
+		t.Fatalf("overlap end = %s, want period end", overlaps[0].Overlap.End.Format(time.RFC3339))
+	}
+}
+
+func TestBuildPrecipTimingBuildsThresholdWindows(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	periods := []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Cloudy", 70, nil, ptr(0), nil, nil),
+		hour(location, "2026-05-29T12:00:00-05:00", "2026-05-29T13:00:00-05:00", "Thunderstorms", 70, nil, ptr(80), nil, nil),
+		hour(location, "2026-05-29T11:00:00-05:00", "2026-05-29T12:00:00-05:00", "Brief lull", 70, nil, ptr(39.999), nil, nil),
+		hour(location, "2026-05-29T13:00:00-05:00", "2026-05-29T14:00:00-05:00", "Unknown rain chance", 70, nil, nil, nil, nil),
+		hour(location, "2026-05-29T10:00:00-05:00", "2026-05-29T11:00:00-05:00", "Rain likely", 70, nil, ptr(60), nil, nil),
+		hour(location, "2026-05-29T09:00:00-05:00", "2026-05-29T10:00:00-05:00", "Showers", 70, nil, ptr(40), nil, nil),
+	}
+
+	timing := BuildPrecipTiming(periods)
+
+	if timing.FirstPrecipitation == nil || timing.FirstPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T09:00:00-05:00" {
+		t.Fatalf("FirstPrecipitation = %#v, want first threshold window start", timing.FirstPrecipitation)
+	}
+	if timing.LastPrecipitation == nil || timing.LastPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T13:00:00-05:00" {
+		t.Fatalf("LastPrecipitation = %#v, want final closed threshold window end", timing.LastPrecipitation)
+	}
+	if timing.MaxPrecipitationProbability == nil || timing.MaxPrecipitationProbability.Value != 80 {
+		t.Fatalf("MaxPrecipitationProbability = %#v, want 80", timing.MaxPrecipitationProbability)
+	}
+	if timing.ProbabilityThreshold != DefaultPrecipWindowProbabilityThreshold {
+		t.Fatalf("ProbabilityThreshold = %v, want default threshold", timing.ProbabilityThreshold)
+	}
+	if len(timing.PrecipitationWindows) != 2 {
+		t.Fatalf("PrecipitationWindows length = %d, want 2: %#v", len(timing.PrecipitationWindows), timing.PrecipitationWindows)
+	}
+	first := timing.PrecipitationWindows[0]
+	if first.Start.Format(time.RFC3339) != "2026-05-29T09:00:00-05:00" || first.End == nil || first.End.Format(time.RFC3339) != "2026-05-29T11:00:00-05:00" {
+		t.Fatalf("first window = %#v, want 9-11 AM", first)
+	}
+	if first.MaxPrecipitationProbability.Value != 60 || first.MaxPrecipitationProbability.Time.Format(time.RFC3339) != "2026-05-29T10:00:00-05:00" {
+		t.Fatalf("first window max = %#v, want 60 at 10 AM", first.MaxPrecipitationProbability)
+	}
+	second := timing.PrecipitationWindows[1]
+	if second.Start.Format(time.RFC3339) != "2026-05-29T12:00:00-05:00" || second.End == nil || second.End.Format(time.RFC3339) != "2026-05-29T13:00:00-05:00" {
+		t.Fatalf("second window = %#v, want noon-1 PM", second)
+	}
+	if !timing.ThunderMentioned {
+		t.Fatal("ThunderMentioned = false, want true")
+	}
+}
+
+func TestBuildPrecipTimingLeavesFinalWindowOpen(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	periods := []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Cloudy", 70, nil, ptr(0), nil, nil),
+		hour(location, "2026-05-29T09:00:00-05:00", "2026-05-29T10:00:00-05:00", "Showers", 70, nil, ptr(45), nil, nil),
+		hour(location, "2026-05-29T10:00:00-05:00", "2026-05-29T11:00:00-05:00", "Rain likely", 70, nil, ptr(60), nil, nil),
+	}
+
+	timing := BuildPrecipTiming(periods)
+
+	if len(timing.PrecipitationWindows) != 1 {
+		t.Fatalf("PrecipitationWindows length = %d, want 1", len(timing.PrecipitationWindows))
+	}
+	if timing.PrecipitationWindows[0].End != nil {
+		t.Fatalf("open window End = %v, want nil", timing.PrecipitationWindows[0].End)
+	}
+	if timing.LastPrecipitation != nil {
+		t.Fatalf("LastPrecipitation = %#v, want nil for open final window", timing.LastPrecipitation)
+	}
+}
+
+func TestBuildPrecipTimingSupportsNonDefaultThreshold(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	periods := []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Showers", 70, nil, ptr(50), nil, nil),
+		hour(location, "2026-05-29T09:00:00-05:00", "2026-05-29T10:00:00-05:00", "Rain likely", 70, nil, ptr(60), nil, nil),
+		hour(location, "2026-05-29T10:00:00-05:00", "2026-05-29T11:00:00-05:00", "Showers", 70, nil, ptr(55), nil, nil),
+		hour(location, "2026-05-29T11:00:00-05:00", "2026-05-29T12:00:00-05:00", "Drying out", 70, nil, ptr(20), nil, nil),
+	}
+
+	timing := buildPrecipTimingWithThreshold(periods, 55)
+
+	if timing.ProbabilityThreshold != 55 {
+		t.Fatalf("ProbabilityThreshold = %v, want 55", timing.ProbabilityThreshold)
+	}
+	if len(timing.PrecipitationWindows) != 1 {
+		t.Fatalf("PrecipitationWindows length = %d, want 1", len(timing.PrecipitationWindows))
+	}
+	window := timing.PrecipitationWindows[0]
+	if window.Start.Format(time.RFC3339) != "2026-05-29T09:00:00-05:00" || window.End == nil || window.End.Format(time.RFC3339) != "2026-05-29T11:00:00-05:00" {
+		t.Fatalf("window = %#v, want 9-11 AM", window)
+	}
+}
+
+func TestBuildPrecipTimingHandlesDryForecast(t *testing.T) {
+	location := time.FixedZone("Test", -5*60*60)
+	periods := []weatherdata.ForecastPeriod{
+		hour(location, "2026-05-29T08:00:00-05:00", "2026-05-29T09:00:00-05:00", "Sunny", 70, nil, ptr(0), nil, nil),
+	}
+
+	timing := BuildPrecipTiming(periods)
+
+	if timing.FirstPrecipitation != nil || timing.LastPrecipitation != nil || len(timing.PrecipitationWindows) != 0 || timing.ThunderMentioned {
+		t.Fatalf("dry timing = %#v, want no precip timing and no thunder", timing)
+	}
+	if timing.ProbabilityThreshold != DefaultPrecipWindowProbabilityThreshold {
+		t.Fatalf("ProbabilityThreshold = %v, want default threshold", timing.ProbabilityThreshold)
+	}
+	if timing.MaxPrecipitationProbability == nil || timing.MaxPrecipitationProbability.Value != 0 {
+		t.Fatalf("dry max precip = %#v, want checked zero chance", timing.MaxPrecipitationProbability)
+	}
+}
+
+func TestThresholdHelpers(t *testing.T) {
+	if !DifferenceAtLeast(50, 56, 5) {
+		t.Fatal("DifferenceAtLeast = false, want true")
+	}
+	if !CrossesAtOrAbove(29, 32, 32) {
+		t.Fatal("CrossesAtOrAbove = false, want true")
+	}
+	if !CrossesBelow(35, 31, 32) {
+		t.Fatal("CrossesBelow = false, want true")
+	}
+}
+
+func testBundle(location *time.Location) *weatherdata.Bundle {
+	return &weatherdata.Bundle{
+		Hourly: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+			hour(location, "2026-05-29T05:00:00-05:00", "2026-05-29T06:00:00-05:00", "Cloudy", 55, nil, nil, nil, nil),
+			hour(location, "2026-05-29T06:00:00-05:00", "2026-05-29T07:00:00-05:00", "Thunderstorms and gusty wind", 58, ptr(57), ptr(70), ptr(22), ptr(40)),
+			hour(location, "2026-05-29T11:00:00-05:00", "2026-05-29T12:00:00-05:00", "Thunderstorms and gusty wind", 72, ptr(74), ptr(60), ptr(18), ptr(35)),
+			hour(location, "2026-05-29T14:00:00-05:00", "2026-05-29T15:00:00-05:00", "Hot and sunny", 96, ptr(100), ptr(5), ptr(10), ptr(12)),
+		}},
+		Narrative: &weatherdata.ForecastRun{Periods: []weatherdata.ForecastPeriod{
+			hour(location, "2026-05-29T06:00:00-05:00", "2026-05-29T18:00:00-05:00", "Storms early, hot later.", 96, nil, nil, nil, nil),
+		}},
+		Alerts: &weatherdata.AlertRun{Alerts: []json.RawMessage{
+			json.RawMessage(`{"event":"Severe Thunderstorm Watch","headline":"Storms possible","severity":"Severe","effective":"2026-05-29T06:30:00-05:00","expires":"2026-05-29T11:30:00-05:00"}`),
+		}},
+		Discussion: &weatherdata.Discussion{Product: "discussion", KeyMessages: []string{"Storms possible."}},
+		Sources:    []weatherdata.Source{{Name: "hourly"}},
+		Warnings:   []weatherdata.SourceWarning{{Source: "daily", Code: "missing_source"}},
+	}
+}
+
+func hour(location *time.Location, start string, end string, text string, temperature float64, apparent *float64, precip *float64, wind *float64, gust *float64) weatherdata.ForecastPeriod {
+	startTime := mustParse(start).In(location)
+	endTime := mustParse(end).In(location)
+	temp := temperature
+	return weatherdata.ForecastPeriod{
+		StartTime:                         startTime,
+		EndTime:                           endTime,
+		TextDescription:                   text,
+		TemperatureF:                      &temp,
+		ApparentTemperatureF:              apparent,
+		ProbabilityOfPrecipitationPercent: precip,
+		WindSpeedMph:                      wind,
+		WindGustMph:                       gust,
+	}
+}
+
+func mustParse(value string) time.Time {
+	parsed, err := time.Parse(time.RFC3339, value)
+	if err != nil {
+		panic(err)
+	}
+	return parsed
+}
+
+func ptr(value float64) *float64 {
+	return &value
+}
+
+func assertRange(t *testing.T, name string, got Range, wantMin float64, wantMax float64) {
+	t.Helper()
+	if got.Min == nil || got.Max == nil {
+		t.Fatalf("%s = %#v, want min and max", name, got)
+	}
+	if *got.Min != wantMin || *got.Max != wantMax {
+		t.Fatalf("%s = [%v,%v], want [%v,%v]", name, *got.Min, *got.Max, wantMin, wantMax)
+	}
+}

internal/forecast/testdata/daily_bundle.json

@@ -0,0 +1,74 @@
+{
+  "fetchedAt": "2026-05-29T15:00:00Z",
+  "hourly": {
+    "issuedAt": "2026-05-29T10:30:00-05:00",
+    "product": "hourly",
+    "periods": [
+      {
+        "startTime": "2026-05-29T06:00:00-05:00",
+        "endTime": "2026-05-29T07:00:00-05:00",
+        "textDescription": "Showers and thunderstorms",
+        "temperatureF": 66,
+        "apparentTemperatureF": 67,
+        "probabilityOfPrecipitationPercent": 80,
+        "windSpeedMph": 18,
+        "windGustMph": 32
+      },
+      {
+        "startTime": "2026-05-29T14:00:00-05:00",
+        "endTime": "2026-05-29T15:00:00-05:00",
+        "textDescription": "Mostly sunny",
+        "temperatureF": 88,
+        "apparentTemperatureF": 91,
+        "probabilityOfPrecipitationPercent": 10,
+        "windSpeedMph": 10,
+        "windGustMph": 16
+      }
+    ]
+  },
+  "narrative": {
+    "issuedAt": "2026-05-29T10:30:00-05:00",
+    "product": "narrative",
+    "periods": [
+      {
+        "startTime": "2026-05-29T06:00:00-05:00",
+        "endTime": "2026-05-29T18:00:00-05:00",
+        "name": "Today",
+        "textDescription": "Morning storms, then partly sunny."
+      }
+    ]
+  },
+  "alerts": {
+    "alerts": [
+      {
+        "event": "Flood Watch",
+        "headline": "Flooding possible",
+        "severity": "Moderate",
+        "effective": "2026-05-29T05:00:00-05:00",
+        "expires": "2026-05-29T09:00:00-05:00"
+      }
+    ]
+  },
+  "discussion": {
+    "product": "discussion",
+    "issuedAt": "2026-05-29T09:25:00-05:00",
+    "keyMessages": [
+      "Storms are most likely during the morning."
+    ],
+    "shortTerm": {
+      "qualifier": "(Through This Evening)",
+      "text": "Morning showers taper as a weak boundary shifts east."
+    },
+    "longTerm": {
+      "qualifier": "(This Weekend)",
+      "text": "Warmer and more humid conditions return with periodic rain chances."
+    }
+  },
+  "sources": [
+    {
+      "name": "hourly",
+      "endpoint": "/forecast/hourly",
+      "fetchedAt": "2026-05-29T15:00:00Z"
+    }
+  ]
+}

internal/forecast/thresholds.go

@@ -0,0 +1,20 @@
+package forecast
+
+func DifferenceAtLeast(previous float64, current float64, threshold float64) bool {
+	return abs(current-previous) >= threshold
+}
+
+func CrossesAtOrAbove(previous float64, current float64, threshold float64) bool {
+	return previous < threshold && current >= threshold
+}
+
+func CrossesBelow(previous float64, current float64, threshold float64) bool {
+	return previous >= threshold && current < threshold
+}
+
+func abs(value float64) float64 {
+	if value < 0 {
+		return -value
+	}
+	return value
+}

internal/module/module.go

@@ -0,0 +1,145 @@
+// Package module defines stable module contracts for prompt-facing stanzas.
+package module
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+const SnapshotSchemaVersion = "weatherreporter.modules.v1"
+
+type ID string
+
+const (
+	Metadata                ID = "metadata"
+	CurrentConditions       ID = "current_conditions"
+	NarrativeForecast       ID = "narrative_forecast"
+	HourlyForecast          ID = "hourly_forecast"
+	DerivedDailySummary     ID = "derived_daily_summary"
+	DerivedDaypartSummaries ID = "derived_daypart_summaries"
+	PrecipTiming            ID = "precip_timing"
+	AlertDigest             ID = "alert_digest"
+	AreaForecastDiscussion  ID = "area_forecast_discussion"
+	WeatherStory            ID = "weather_story"
+	OutdoorWindows          ID = "outdoor_windows"
+	TomorrowPlanning        ID = "tomorrow_planning"
+)
+
+type ConfigItem struct {
+	ID      ID  `json:"id"`
+	Options any `json:"options,omitempty"`
+}
+
+type Output struct {
+	ID         ID     `json:"id"`
+	StanzaName string `json:"stanzaName"`
+	Value      any    `json:"value"`
+}
+
+type Snapshot struct {
+	SchemaVersion string   `json:"schemaVersion"`
+	Outputs       []Output `json:"outputs"`
+}
+
+func NewSnapshot(outputs []Output) (Snapshot, error) {
+	snapshot := Snapshot{
+		SchemaVersion: SnapshotSchemaVersion,
+		Outputs:       append([]Output(nil), outputs...),
+	}
+	if err := snapshot.Validate(); err != nil {
+		return Snapshot{}, err
+	}
+	return snapshot, nil
+}
+
+func (s Snapshot) Validate() error {
+	if s.SchemaVersion == "" {
+		return fmt.Errorf("schemaVersion is required")
+	}
+	seenModules := map[ID]struct{}{}
+	seenStanzas := map[string]struct{}{}
+	for i, output := range s.Outputs {
+		if output.ID == "" {
+			return fmt.Errorf("outputs[%d].id is required", i)
+		}
+		if output.StanzaName == "" {
+			return fmt.Errorf("outputs[%d].stanzaName is required", i)
+		}
+		if _, ok := seenModules[output.ID]; ok {
+			return fmt.Errorf("duplicate module output %q", output.ID)
+		}
+		seenModules[output.ID] = struct{}{}
+		if _, ok := seenStanzas[output.StanzaName]; ok {
+			return fmt.Errorf("duplicate stanza name %q", output.StanzaName)
+		}
+		seenStanzas[output.StanzaName] = struct{}{}
+	}
+	return nil
+}
+
+func (s Snapshot) LookupStanza(name string) (Output, bool) {
+	for _, output := range s.Outputs {
+		if output.StanzaName == name {
+			return output, true
+		}
+	}
+	return Output{}, false
+}
+
+func StanzaValue[T any](s Snapshot, name string) (T, bool, error) {
+	var zero T
+	output, ok := s.LookupStanza(name)
+	if !ok {
+		return zero, false, nil
+	}
+	data, err := json.Marshal(output.Value)
+	if err != nil {
+		return zero, true, fmt.Errorf("marshal stanza %q: %w", name, err)
+	}
+	if err := json.Unmarshal(data, &zero); err != nil {
+		return zero, true, fmt.Errorf("decode stanza %q: %w", name, err)
+	}
+	return zero, true, nil
+}
+
+type FactRequirement string
+
+const (
+	CollectedCurrentConditions      FactRequirement = "collected.current_conditions"
+	CollectedNarrativeForecast      FactRequirement = "collected.narrative_forecast"
+	CollectedHourlyForecast         FactRequirement = "collected.hourly_forecast"
+	CollectedAlerts                 FactRequirement = "collected.alerts"
+	CollectedDiscussion             FactRequirement = "collected.discussion"
+	CollectedWeatherStory           FactRequirement = "collected.weather_story"
+	CollectedSourceMetadata         FactRequirement = "collected.source_metadata"
+	RequiresDerivedHourlyPeriods    FactRequirement = "derived.hourly_periods"
+	RequiresDerivedNarrativePeriods FactRequirement = "derived.narrative_periods"
+	RequiresDerivedAlertOverlaps    FactRequirement = "derived.alert_overlaps"
+	RequiresDerivedDailySummaries   FactRequirement = "derived.daily_summaries"
+	RequiresDerivedDaypartSummaries FactRequirement = "derived.daypart_summaries"
+	RequiresDerivedPrecipTiming     FactRequirement = "derived.precip_timing"
+)
+
+type MissingDataBehavior string
+
+const (
+	MissingDataOmit  MissingDataBehavior = "omit"
+	MissingDataEmpty MissingDataBehavior = "empty"
+	MissingDataError MissingDataBehavior = "error"
+	MissingDataWarn  MissingDataBehavior = "warn"
+)
+
+type MetadataOptions struct{}
+type CurrentConditionsOptions struct{}
+type NarrativeForecastOptions struct{}
+type HourlyForecastOptions struct{}
+type DerivedDailySummaryOptions struct{}
+type DerivedDaypartSummariesOptions struct{}
+type PrecipTimingOptions struct{}
+type AlertDigestOptions struct{}
+type AreaForecastDiscussionOptions struct {
+	Sections []string `json:"sections,omitempty" yaml:"sections,omitempty"`
+}
+type WeatherStoryOptions struct{}
+type OutdoorWindowsOptions struct{}
+type TomorrowPlanningOptions struct{}

internal/module/module_test.go

@@ -0,0 +1,84 @@
+package module
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+type testStanza struct {
+	Message string `json:"message"`
+	Count   int    `json:"count"`
+}
+
+func TestSnapshotPreservesOutputOrderAndJSON(t *testing.T) {
+	snapshot, err := NewSnapshot([]Output{
+		{ID: Metadata, StanzaName: "metadata", Value: testStanza{Message: "first", Count: 1}},
+		{ID: AlertDigest, StanzaName: "alert_digest", Value: testStanza{Message: "second", Count: 2}},
+	})
+	if err != nil {
+		t.Fatalf("NewSnapshot() error = %v", err)
+	}
+	if snapshot.SchemaVersion != SnapshotSchemaVersion {
+		t.Fatalf("SchemaVersion = %q, want %q", snapshot.SchemaVersion, SnapshotSchemaVersion)
+	}
+	if snapshot.Outputs[0].ID != Metadata || snapshot.Outputs[1].ID != AlertDigest {
+		t.Fatalf("Outputs order = %#v, want input order", snapshot.Outputs)
+	}
+
+	data, err := json.Marshal(snapshot)
+	if err != nil {
+		t.Fatalf("Marshal() error = %v", err)
+	}
+	got := string(data)
+	want := `{"schemaVersion":"weatherreporter.modules.v1","outputs":[{"id":"metadata","stanzaName":"metadata","value":{"message":"first","count":1}},{"id":"alert_digest","stanzaName":"alert_digest","value":{"message":"second","count":2}}]}`
+	if got != want {
+		t.Fatalf("json = %s, want %s", got, want)
+	}
+}
+
+func TestSnapshotRejectsDuplicateOutputs(t *testing.T) {
+	_, err := NewSnapshot([]Output{
+		{ID: Metadata, StanzaName: "metadata", Value: struct{}{}},
+		{ID: Metadata, StanzaName: "other_metadata", Value: struct{}{}},
+	})
+	if err == nil || !strings.Contains(err.Error(), `duplicate module output "metadata"`) {
+		t.Fatalf("duplicate module error = %v, want duplicate module output", err)
+	}
+
+	_, err = NewSnapshot([]Output{
+		{ID: Metadata, StanzaName: "metadata", Value: struct{}{}},
+		{ID: CurrentConditions, StanzaName: "metadata", Value: struct{}{}},
+	})
+	if err == nil || !strings.Contains(err.Error(), `duplicate stanza name "metadata"`) {
+		t.Fatalf("duplicate stanza error = %v, want duplicate stanza name", err)
+	}
+}
+
+func TestStanzaValueDecodesTypedOutput(t *testing.T) {
+	snapshot, err := NewSnapshot([]Output{
+		{ID: Metadata, StanzaName: "metadata", Value: testStanza{Message: "available", Count: 3}},
+	})
+	if err != nil {
+		t.Fatalf("NewSnapshot() error = %v", err)
+	}
+
+	value, found, err := StanzaValue[testStanza](snapshot, "metadata")
+	if err != nil {
+		t.Fatalf("StanzaValue() error = %v", err)
+	}
+	if !found {
+		t.Fatal("StanzaValue() found = false, want true")
+	}
+	if value.Message != "available" || value.Count != 3 {
+		t.Fatalf("StanzaValue() = %#v, want decoded stanza", value)
+	}
+
+	_, found, err = StanzaValue[testStanza](snapshot, "missing")
+	if err != nil {
+		t.Fatalf("StanzaValue(missing) error = %v", err)
+	}
+	if found {
+		t.Fatal("StanzaValue(missing) found = true, want false")
+	}
+}

internal/promptinput/package.go

@@ -0,0 +1,402 @@
+// Package promptinput builds prompt data packages from module snapshots.
+package promptinput
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/changes"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/fileutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
+	"gopkg.in/yaml.v3"
+)
+
+const SchemaVersion = "weatherreporter.data_package.v2"
+
+const (
+	metadataStanza                 = "metadata"
+	categoryApplicableRiskProducts = "applicable_risk_products"
+	categoryDerivedSummaries       = "derived_summaries"
+	categoryNarrativeProducts      = "narrative_products"
+	categoryRawData                = "raw_data"
+)
+
+var briefingCategoryOrder = []string{
+	categoryApplicableRiskProducts,
+	categoryDerivedSummaries,
+	categoryNarrativeProducts,
+	categoryRawData,
+}
+
+var briefingStanzaCategories = map[string]string{
+	string(module.AlertDigest):             categoryApplicableRiskProducts,
+	string(module.DerivedDailySummary):     categoryDerivedSummaries,
+	string(module.DerivedDaypartSummaries): categoryDerivedSummaries,
+	string(module.PrecipTiming):            categoryDerivedSummaries,
+	string(module.OutdoorWindows):          categoryDerivedSummaries,
+	string(module.TomorrowPlanning):        categoryDerivedSummaries,
+	string(module.NarrativeForecast):       categoryNarrativeProducts,
+	string(module.AreaForecastDiscussion):  categoryNarrativeProducts,
+	string(module.WeatherStory):            categoryNarrativeProducts,
+	string(module.CurrentConditions):       categoryRawData,
+	string(module.HourlyForecast):          categoryRawData,
+}
+
+type BuildRequest struct {
+	Metadata      Metadata
+	Modules       module.Snapshot
+	RecentChanges []changes.Change
+}
+
+type Metadata struct {
+	RunID          string
+	ReportID       report.ID
+	Variant        string
+	PromptID       string
+	GeneratedAt    time.Time
+	Timezone       string
+	ValidPeriod    timeutil.Period
+	SourceWarnings []weatherdata.SourceWarning
+}
+
+type Package struct {
+	SchemaVersion  string                      `json:"schemaVersion" yaml:"schema_version"`
+	RunID          string                      `json:"runId" yaml:"run_id"`
+	Report         Report                      `json:"report" yaml:"report"`
+	Briefing       BriefingStanzas             `json:"briefing" yaml:"briefing"`
+	RecentChanges  RecentChanges               `json:"recentChanges" yaml:"recent_changes"`
+	SourceWarnings []weatherdata.SourceWarning `json:"sourceWarnings,omitempty" yaml:"source_warnings,omitempty"`
+}
+
+type Report struct {
+	ID               report.ID       `json:"id" yaml:"id"`
+	Variant          string          `json:"variant,omitempty" yaml:"variant,omitempty"`
+	PromptID         string          `json:"promptId" yaml:"prompt_id"`
+	GeneratedAt      time.Time       `json:"generatedAt" yaml:"generated_at"`
+	Timezone         string          `json:"timezone" yaml:"timezone"`
+	CurrentLocalDate string          `json:"currentLocalDate" yaml:"current_local_date"`
+	ValidPeriod      timeutil.Period `json:"validPeriod" yaml:"valid_period"`
+}
+
+type BriefingStanzas struct {
+	Order  []string       `json:"-" yaml:"-"`
+	Values map[string]any `json:"-" yaml:"-"`
+}
+
+type RecentChanges struct {
+	Items []changes.Change `json:"items" yaml:"items"`
+}
+
+func Build(req BuildRequest) (Package, error) {
+	localDate, err := currentLocalDate(req.Metadata.GeneratedAt, req.Metadata.Timezone)
+	if err != nil {
+		return Package{}, err
+	}
+	items := make([]changes.Change, len(req.RecentChanges))
+	copy(items, req.RecentChanges)
+	if items == nil {
+		items = []changes.Change{}
+	}
+	pkg := Package{
+		SchemaVersion: SchemaVersion,
+		RunID:         req.Metadata.RunID,
+		Report: Report{
+			ID:               req.Metadata.ReportID,
+			Variant:          req.Metadata.Variant,
+			PromptID:         req.Metadata.PromptID,
+			GeneratedAt:      req.Metadata.GeneratedAt,
+			Timezone:         req.Metadata.Timezone,
+			CurrentLocalDate: localDate,
+			ValidPeriod:      req.Metadata.ValidPeriod,
+		},
+		Briefing:       stanzasFromSnapshot(req.Modules),
+		RecentChanges:  RecentChanges{Items: items},
+		SourceWarnings: append([]weatherdata.SourceWarning(nil), req.Metadata.SourceWarnings...),
+	}
+	if err := Validate(pkg); err != nil {
+		return Package{}, err
+	}
+	return pkg, nil
+}
+
+func stanzasFromSnapshot(snapshot module.Snapshot) BriefingStanzas {
+	values := map[string]any{}
+	order := make([]string, 0, len(snapshot.Outputs))
+	for _, output := range snapshot.Outputs {
+		order = append(order, output.StanzaName)
+		values[output.StanzaName] = output.Value
+	}
+	return BriefingStanzas{Order: order, Values: values}
+}
+
+func currentLocalDate(generatedAt time.Time, timezone string) (string, error) {
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		return "", fmt.Errorf("load report timezone %q: %w", timezone, err)
+	}
+	return generatedAt.In(location).Format(timeutil.DateLayout), nil
+}
+
+func Validate(pkg Package) error {
+	if pkg.SchemaVersion == "" {
+		return fmt.Errorf("schemaVersion is required")
+	}
+	if pkg.SchemaVersion != SchemaVersion {
+		return fmt.Errorf("schemaVersion must be %s", SchemaVersion)
+	}
+	if pkg.RunID == "" {
+		return fmt.Errorf("runId is required")
+	}
+	if pkg.Report.ID == "" {
+		return fmt.Errorf("report.id is required")
+	}
+	if pkg.Report.PromptID == "" {
+		return fmt.Errorf("report.promptId is required")
+	}
+	if pkg.Report.GeneratedAt.IsZero() {
+		return fmt.Errorf("report.generatedAt is required")
+	}
+	if pkg.Report.Timezone == "" {
+		return fmt.Errorf("report.timezone is required")
+	}
+	if pkg.Report.CurrentLocalDate == "" {
+		return fmt.Errorf("report.currentLocalDate is required")
+	}
+	if !pkg.Report.ValidPeriod.IsValid() {
+		return fmt.Errorf("report.validPeriod must be valid")
+	}
+	if len(pkg.Briefing.Order) == 0 {
+		return fmt.Errorf("briefing stanzas are required")
+	}
+	seen := map[string]struct{}{}
+	for _, name := range pkg.Briefing.Order {
+		if name == "" {
+			return fmt.Errorf("briefing stanza name is required")
+		}
+		if _, ok := seen[name]; ok {
+			return fmt.Errorf("duplicate briefing stanza %q", name)
+		}
+		seen[name] = struct{}{}
+		if _, ok := pkg.Briefing.Values[name]; !ok {
+			return fmt.Errorf("briefing stanza %q is missing", name)
+		}
+		if name == metadataStanza {
+			continue
+		}
+		if _, ok := briefingStanzaCategories[name]; !ok {
+			return fmt.Errorf("briefing stanza %q has no prompt-input category", name)
+		}
+	}
+	return nil
+}
+
+func Save(path string, pkg Package) error {
+	data, err := MarshalYAML(pkg)
+	if err != nil {
+		return err
+	}
+	if err := fileutil.WriteFileAtomic(path, data); err != nil {
+		return fmt.Errorf("save data package: %w", err)
+	}
+	return nil
+}
+
+func MarshalYAML(pkg Package) ([]byte, error) {
+	if err := Validate(pkg); err != nil {
+		return nil, err
+	}
+	data, err := yaml.Marshal(pkg)
+	if err != nil {
+		return nil, fmt.Errorf("marshal data package: %w", err)
+	}
+	return data, nil
+}
+
+func LoadYAML(data []byte) (Package, error) {
+	var pkg Package
+	decoder := yaml.NewDecoder(bytes.NewReader(data))
+	if err := decoder.Decode(&pkg); err != nil {
+		return Package{}, fmt.Errorf("decode data package: %w", err)
+	}
+	if err := Validate(pkg); err != nil {
+		return Package{}, err
+	}
+	return pkg, nil
+}
+
+func (b BriefingStanzas) MarshalYAML() (any, error) {
+	node := &yaml.Node{Kind: yaml.MappingNode}
+	categoryNames := map[string][]string{}
+	for _, name := range b.Order {
+		value, ok := b.Values[name]
+		if !ok {
+			continue
+		}
+		if name == metadataStanza {
+			if err := appendYAMLMappingValue(node, name, value); err != nil {
+				return nil, err
+			}
+			continue
+		}
+		category, ok := briefingStanzaCategories[name]
+		if !ok {
+			return nil, fmt.Errorf("briefing stanza %q has no prompt-input category", name)
+		}
+		categoryNames[category] = append(categoryNames[category], name)
+	}
+	for _, category := range briefingCategoryOrder {
+		names := categoryNames[category]
+		if len(names) == 0 {
+			continue
+		}
+		categoryNode := &yaml.Node{Kind: yaml.MappingNode}
+		for _, name := range names {
+			value := b.Values[name]
+			if err := appendYAMLMappingValue(categoryNode, name, value); err != nil {
+				return nil, err
+			}
+		}
+		node.Content = append(node.Content,
+			&yaml.Node{Kind: yaml.ScalarNode, Value: category},
+			categoryNode,
+		)
+	}
+	return node, nil
+}
+
+func (b *BriefingStanzas) UnmarshalYAML(value *yaml.Node) error {
+	if value.Kind != yaml.MappingNode {
+		return fmt.Errorf("briefing must be a mapping")
+	}
+	values := map[string]any{}
+	order := make([]string, 0, len(value.Content)/2)
+	seen := map[string]struct{}{}
+	seenCategories := map[string]struct{}{}
+	categoryOrder := map[string][]string{}
+	for i := 0; i < len(value.Content); i += 2 {
+		name := value.Content[i].Value
+		if name == metadataStanza {
+			if err := decodeBriefingStanza(value.Content[i+1], name, values, &order, seen); err != nil {
+				return err
+			}
+			continue
+		}
+		if !knownBriefingCategory(name) {
+			return fmt.Errorf("unknown briefing category %q", name)
+		}
+		if _, ok := seenCategories[name]; ok {
+			return fmt.Errorf("duplicate briefing category %q", name)
+		}
+		seenCategories[name] = struct{}{}
+		categoryNode := value.Content[i+1]
+		if categoryNode.Kind != yaml.MappingNode {
+			return fmt.Errorf("briefing category %q must be a mapping", name)
+		}
+		var names []string
+		for j := 0; j < len(categoryNode.Content); j += 2 {
+			stanzaName := categoryNode.Content[j].Value
+			category, ok := briefingStanzaCategories[stanzaName]
+			if !ok {
+				return fmt.Errorf("briefing stanza %q has no prompt-input category", stanzaName)
+			}
+			if category != name {
+				return fmt.Errorf("briefing stanza %q belongs under category %q, not %q", stanzaName, category, name)
+			}
+			if err := decodeBriefingStanza(categoryNode.Content[j+1], stanzaName, values, &names, seen); err != nil {
+				return err
+			}
+		}
+		categoryOrder[name] = names
+	}
+	for _, category := range briefingCategoryOrder {
+		order = append(order, categoryOrder[category]...)
+	}
+	b.Order = order
+	b.Values = values
+	return nil
+}
+
+func (b BriefingStanzas) MarshalJSON() ([]byte, error) {
+	out := map[string]any{}
+	for _, name := range b.Order {
+		if value, ok := b.Values[name]; ok {
+			out[name] = value
+		}
+	}
+	return json.Marshal(out)
+}
+
+func (b *BriefingStanzas) UnmarshalJSON(data []byte) error {
+	var values map[string]any
+	if err := json.Unmarshal(data, &values); err != nil {
+		return err
+	}
+	order := make([]string, 0, len(values))
+	for name := range values {
+		order = append(order, name)
+	}
+	b.Order = order
+	b.Values = values
+	return nil
+}
+
+func appendYAMLMappingValue(node *yaml.Node, name string, value any) error {
+	keyNode := &yaml.Node{Kind: yaml.ScalarNode, Value: name}
+	valueNode, err := yamlNode(value)
+	if err != nil {
+		return fmt.Errorf("marshal briefing stanza %q: %w", name, err)
+	}
+	node.Content = append(node.Content, keyNode, valueNode)
+	return nil
+}
+
+func decodeBriefingStanza(node *yaml.Node, name string, values map[string]any, order *[]string, seen map[string]struct{}) error {
+	if _, ok := seen[name]; ok {
+		return fmt.Errorf("duplicate briefing stanza %q", name)
+	}
+	var stanza any
+	if err := node.Decode(&stanza); err != nil {
+		return err
+	}
+	seen[name] = struct{}{}
+	*order = append(*order, name)
+	values[name] = stanza
+	return nil
+}
+
+func knownBriefingCategory(name string) bool {
+	for _, category := range briefingCategoryOrder {
+		if name == category {
+			return true
+		}
+	}
+	return false
+}
+
+func yamlNode(value any) (*yaml.Node, error) {
+	data, err := json.Marshal(value)
+	if err != nil {
+		return nil, err
+	}
+	var normalized any
+	if err := json.Unmarshal(data, &normalized); err != nil {
+		return nil, err
+	}
+	data, err = yaml.Marshal(normalized)
+	if err != nil {
+		return nil, err
+	}
+	var node yaml.Node
+	if err := yaml.Unmarshal(data, &node); err != nil {
+		return nil, err
+	}
+	if len(node.Content) == 0 {
+		return &yaml.Node{Kind: yaml.MappingNode}, nil
+	}
+	return node.Content[0], nil
+}

internal/promptinput/package_test.go

@@ -0,0 +1,266 @@
+package promptinput
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+func TestBuildDailyDataPackage(t *testing.T) {
+	pkg, err := Build(validBuildRequest(t))
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+
+	if pkg.SchemaVersion != SchemaVersion {
+		t.Fatalf("SchemaVersion = %q, want %q", pkg.SchemaVersion, SchemaVersion)
+	}
+	if pkg.RunID != "20260529T100000Z_daily_today" {
+		t.Fatalf("RunID = %q, want metadata run id", pkg.RunID)
+	}
+	if pkg.Report.PromptID != "weather.daily_report" {
+		t.Fatalf("PromptID = %q, want weather.daily_report", pkg.Report.PromptID)
+	}
+	if pkg.Report.CurrentLocalDate != "2026-05-29" {
+		t.Fatalf("CurrentLocalDate = %q, want 2026-05-29", pkg.Report.CurrentLocalDate)
+	}
+	if pkg.Briefing.Order[0] != "metadata" || pkg.Briefing.Order[1] != "current_conditions" || pkg.Briefing.Order[2] != "derived_daily_summary" {
+		t.Fatalf("Briefing.Order = %#v, want snapshot stanza order", pkg.Briefing.Order)
+	}
+	if got := pkg.Briefing.Values["current_conditions"].(map[string]string)["condition_text"]; got != "Partly cloudy" {
+		t.Fatalf("current_conditions.condition_text = %q, want Partly cloudy", got)
+	}
+	if pkg.RecentChanges.Items == nil || len(pkg.RecentChanges.Items) != 0 {
+		t.Fatalf("RecentChanges.Items = %#v, want empty slice", pkg.RecentChanges.Items)
+	}
+}
+
+func TestBuildCurrentLocalDateUsesReportTimezone(t *testing.T) {
+	req := validBuildRequest(t)
+	req.Metadata.GeneratedAt = time.Date(2026, 5, 30, 2, 30, 0, 0, time.UTC)
+	req.Metadata.Timezone = "America/Chicago"
+
+	pkg, err := Build(req)
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+
+	if pkg.Report.CurrentLocalDate != "2026-05-29" {
+		t.Fatalf("CurrentLocalDate = %q, want local Chicago date 2026-05-29", pkg.Report.CurrentLocalDate)
+	}
+}
+
+func TestBuildRejectsInvalidReportTimezone(t *testing.T) {
+	req := validBuildRequest(t)
+	req.Metadata.Timezone = "Not/AZone"
+
+	_, err := Build(req)
+	if err == nil {
+		t.Fatal("Build() error = nil, want invalid timezone error")
+	}
+	if !strings.Contains(err.Error(), "report timezone") {
+		t.Fatalf("error = %q, want report timezone context", err.Error())
+	}
+}
+
+func TestValidateRequiresFields(t *testing.T) {
+	pkg, err := Build(validBuildRequest(t))
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+	pkg.RunID = ""
+
+	err = Validate(pkg)
+	if err == nil {
+		t.Fatal("Validate() error = nil, want required field error")
+	}
+	if !strings.Contains(err.Error(), "runId") {
+		t.Fatalf("error = %q, want runId context", err.Error())
+	}
+}
+
+func TestValidateRequiresCurrentLocalDate(t *testing.T) {
+	pkg, err := Build(validBuildRequest(t))
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+	pkg.Report.CurrentLocalDate = ""
+
+	err = Validate(pkg)
+	if err == nil {
+		t.Fatal("Validate() error = nil, want required field error")
+	}
+	if !strings.Contains(err.Error(), "currentLocalDate") {
+		t.Fatalf("error = %q, want currentLocalDate context", err.Error())
+	}
+}
+
+func TestBuildUsesNamedSnapshotStanzas(t *testing.T) {
+	req := validBuildRequest(t)
+	req.Metadata.RunID = "20260529T100000Z_three_day"
+	req.Metadata.ReportID = report.ThreeDay
+	req.Metadata.PromptID = "weather.three_day_outlook"
+	req.Modules = snapshotWithOutputs(t,
+		module.Output{ID: module.Metadata, StanzaName: "metadata", Value: map[string]string{"run_id": req.Metadata.RunID}},
+		module.Output{ID: module.DerivedDaypartSummaries, StanzaName: "derived_daypart_summaries", Value: map[string]any{"days": []string{"2026-05-29"}}},
+	)
+
+	pkg, err := Build(req)
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+
+	if pkg.Report.ID != report.ThreeDay {
+		t.Fatalf("Report.ID = %q, want three_day", pkg.Report.ID)
+	}
+	if _, ok := pkg.Briefing.Values["derived_daypart_summaries"]; !ok {
+		t.Fatal("Briefing.Values[derived_daypart_summaries] missing")
+	}
+}
+
+func TestMarshalYAMLIsDeterministicAndGroupsNamedStanzas(t *testing.T) {
+	pkg, err := Build(validBuildRequest(t))
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+
+	first, err := MarshalYAML(pkg)
+	if err != nil {
+		t.Fatalf("first marshal: %v", err)
+	}
+	second, err := MarshalYAML(pkg)
+	if err != nil {
+		t.Fatalf("second marshal: %v", err)
+	}
+	if string(first) != string(second) {
+		t.Fatalf("YAML output changed between marshals:\n%s\n---\n%s", string(first), string(second))
+	}
+	if !strings.Contains(string(first), "schema_version: weatherreporter.data_package.v2") ||
+		!strings.Contains(string(first), "briefing:\n") ||
+		!strings.Contains(string(first), "  applicable_risk_products:\n") ||
+		!strings.Contains(string(first), "  derived_summaries:\n") ||
+		!strings.Contains(string(first), "  narrative_products:\n") ||
+		!strings.Contains(string(first), "  raw_data:\n") ||
+		!strings.Contains(string(first), "    current_conditions:\n") ||
+		!strings.Contains(string(first), "      condition_text: Partly cloudy") {
+		t.Fatalf("YAML output missing expected grouped stanzas:\n%s", string(first))
+	}
+	for _, pair := range []struct {
+		before string
+		after  string
+	}{
+		{before: "  metadata:\n", after: "  applicable_risk_products:\n"},
+		{before: "  applicable_risk_products:\n", after: "  derived_summaries:\n"},
+		{before: "  derived_summaries:\n", after: "  narrative_products:\n"},
+		{before: "  narrative_products:\n", after: "  raw_data:\n"},
+	} {
+		if strings.Index(string(first), pair.before) < 0 || strings.Index(string(first), pair.after) < 0 || strings.Index(string(first), pair.before) > strings.Index(string(first), pair.after) {
+			t.Fatalf("YAML category order is wrong, want %q before %q:\n%s", pair.before, pair.after, string(first))
+		}
+	}
+}
+
+func TestLoadYAMLRoundTrip(t *testing.T) {
+	pkg, err := Build(validBuildRequest(t))
+	if err != nil {
+		t.Fatalf("Build() error = %v", err)
+	}
+	data, err := MarshalYAML(pkg)
+	if err != nil {
+		t.Fatalf("MarshalYAML() error = %v", err)
+	}
+
+	loaded, err := LoadYAML(data)
+	if err != nil {
+		t.Fatalf("LoadYAML() error = %v", err)
+	}
+
+	if loaded.SchemaVersion != SchemaVersion || loaded.RunID != pkg.RunID {
+		t.Fatalf("loaded package = %#v, want schema and run id", loaded)
+	}
+	wantOrder := []string{"metadata", "alert_digest", "derived_daily_summary", "narrative_forecast", "current_conditions"}
+	if strings.Join(loaded.Briefing.Order, ",") != strings.Join(wantOrder, ",") {
+		t.Fatalf("loaded package order = %#v, want grouped category order %#v", loaded.Briefing.Order, wantOrder)
+	}
+	if got := loaded.Briefing.Values["current_conditions"].(map[string]any)["condition_text"]; got != "Partly cloudy" {
+		t.Fatalf("loaded current_conditions.condition_text = %#v, want Partly cloudy", got)
+	}
+}
+
+func TestMarshalYAMLRejectsUncategorizedStanza(t *testing.T) {
+	req := validBuildRequest(t)
+	req.Modules = snapshotWithOutputs(t, module.Output{ID: module.ID("custom"), StanzaName: "custom", Value: map[string]string{"value": "x"}})
+
+	_, err := Build(req)
+	if err == nil || !strings.Contains(err.Error(), `briefing stanza "custom" has no prompt-input category`) {
+		t.Fatalf("Build() error = %v, want uncategorized stanza error", err)
+	}
+}
+
+func TestLoadYAMLRejectsMisplacedStanza(t *testing.T) {
+	data := []byte(`
+schema_version: weatherreporter.data_package.v2
+run_id: 20260529T100000Z_daily_today
+report:
+  id: daily_today
+  prompt_id: weather.daily_report
+  generated_at: 2026-05-29T10:00:00Z
+  timezone: America/Chicago
+  current_local_date: "2026-05-29"
+  valid_period:
+    start: 2026-05-29T05:00:00Z
+    end: 2026-05-30T05:00:00Z
+briefing:
+  metadata:
+    run_id: 20260529T100000Z_daily_today
+  raw_data:
+    alert_digest:
+      checked: true
+recent_changes:
+  items: []
+`)
+
+	_, err := LoadYAML(data)
+	if err == nil || !strings.Contains(err.Error(), `briefing stanza "alert_digest" belongs under category "applicable_risk_products"`) {
+		t.Fatalf("LoadYAML() error = %v, want misplaced stanza error", err)
+	}
+}
+
+func validBuildRequest(t *testing.T) BuildRequest {
+	t.Helper()
+	generatedAt := time.Date(2026, 5, 29, 10, 0, 0, 0, time.UTC)
+	return BuildRequest{
+		Metadata: Metadata{
+			RunID:       "20260529T100000Z_daily_today",
+			ReportID:    report.DailyToday,
+			Variant:     "today",
+			PromptID:    "weather.daily_report",
+			GeneratedAt: generatedAt,
+			Timezone:    "America/Chicago",
+			ValidPeriod: timeutil.Period{
+				Start: time.Date(2026, 5, 29, 5, 0, 0, 0, time.UTC),
+				End:   time.Date(2026, 5, 30, 5, 0, 0, 0, time.UTC),
+			},
+		},
+		Modules: snapshotWithOutputs(t,
+			module.Output{ID: module.Metadata, StanzaName: "metadata", Value: map[string]string{"run_id": "20260529T100000Z_daily_today"}},
+			module.Output{ID: module.CurrentConditions, StanzaName: "current_conditions", Value: map[string]string{"condition_text": "Partly cloudy"}},
+			module.Output{ID: module.DerivedDailySummary, StanzaName: "derived_daily_summary", Value: map[string]string{"date": "2026-05-29"}},
+			module.Output{ID: module.AlertDigest, StanzaName: "alert_digest", Value: map[string]bool{"checked": true}},
+			module.Output{ID: module.NarrativeForecast, StanzaName: "narrative_forecast", Value: map[string]string{"product": "narrative"}},
+		),
+	}
+}
+
+func snapshotWithOutputs(t *testing.T, outputs ...module.Output) module.Snapshot {
+	t.Helper()
+	snapshot, err := module.NewSnapshot(outputs)
+	if err != nil {
+		t.Fatalf("NewSnapshot() error = %v", err)
+	}
+	return snapshot
+}

internal/report/daily_report.go

@@ -0,0 +1,82 @@
+package report
+
+import (
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+func dailyTodayDefinition() Definition {
+	return Definition{
+		ID:                 DailyToday,
+		Name:               "Daily Report",
+		PromptID:           "weather.daily_report",
+		ComparisonStrategy: CompareSameValidDate,
+		ArtifactGroup:      "daily",
+		BatchOutputName:    "daily.md",
+		Generated:          true,
+		CompatiblePriorIDs: []ID{DailyToday, DailyTomorrow},
+		Modules:            dailyTodayModules(),
+		Morning:            true,
+		resolve:            resolveDailyToday,
+	}
+}
+
+func dailyTomorrowDefinition() Definition {
+	return Definition{
+		ID:                 DailyTomorrow,
+		Name:               "Tomorrow Planning Brief",
+		PromptID:           "weather.daily_report",
+		ComparisonStrategy: CompareSameValidDate,
+		ArtifactGroup:      "daily",
+		BatchOutputName:    "tomorrow.md",
+		Generated:          true,
+		CompatiblePriorIDs: []ID{DailyToday, DailyTomorrow},
+		Modules:            dailyTomorrowModules(),
+		Evening:            true,
+		resolve:            resolveDailyTomorrow,
+	}
+}
+
+func dailyTodayModules() []module.ConfigItem {
+	return moduleItems(
+		module.Metadata,
+		module.CurrentConditions,
+		module.NarrativeForecast,
+		module.DerivedDailySummary,
+		module.DerivedDaypartSummaries,
+		module.PrecipTiming,
+		module.AlertDigest,
+		module.AreaForecastDiscussion,
+		module.WeatherStory,
+		module.OutdoorWindows,
+		module.HourlyForecast,
+	)
+}
+
+func dailyTomorrowModules() []module.ConfigItem {
+	return moduleItems(
+		module.Metadata,
+		module.CurrentConditions,
+		module.NarrativeForecast,
+		module.DerivedDailySummary,
+		module.DerivedDaypartSummaries,
+		module.PrecipTiming,
+		module.AlertDigest,
+		module.AreaForecastDiscussion,
+		module.WeatherStory,
+		module.OutdoorWindows,
+		module.TomorrowPlanning,
+		module.HourlyForecast,
+	)
+}
+
+func resolveDailyToday(req ResolveRequest) (timeutil.Period, error) {
+	if !req.Date.IsZero() {
+		return timeutil.CivilDay(req.Date, req.Location), nil
+	}
+	return timeutil.CivilDay(req.Now, req.Location), nil
+}
+
+func resolveDailyTomorrow(req ResolveRequest) (timeutil.Period, error) {
+	return timeutil.CivilDay(req.Now.In(req.Location).AddDate(0, 0, 1), req.Location), nil
+}

internal/report/definition.go

@@ -0,0 +1,109 @@
+// Package report defines report identities, registry metadata, and valid periods.
+package report
+
+import (
+	"fmt"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+type ID string
+
+const (
+	DailyToday    ID = "daily_today"
+	DailyTomorrow ID = "daily_tomorrow"
+	ThreeDay      ID = "three_day"
+	Weekend       ID = "weekend"
+	Storm         ID = "storm"
+)
+
+type ComparisonStrategy string
+
+const (
+	CompareSameValidDate  ComparisonStrategy = "same_valid_date"
+	CompareWeekendWindow  ComparisonStrategy = "same_weekend_window"
+	CompareExplicitWindow ComparisonStrategy = "explicit_event_window"
+)
+
+type Batch string
+
+const (
+	Morning Batch = "morning"
+	Evening Batch = "evening"
+)
+
+type Definition struct {
+	ID                 ID
+	Name               string
+	PromptID           string
+	ComparisonStrategy ComparisonStrategy
+	ArtifactGroup      string
+	BatchOutputName    string
+	Generated          bool
+	CompatiblePriorIDs []ID
+	Modules            []module.ConfigItem
+	Morning            bool
+	Evening            bool
+	resolve            func(ResolveRequest) (timeutil.Period, error)
+}
+
+func (d Definition) ResolvePeriod(req ResolveRequest) (timeutil.Period, error) {
+	if d.resolve == nil {
+		return timeutil.Period{}, fmt.Errorf("report %q has no valid-period resolver", d.ID)
+	}
+	return d.resolve(req)
+}
+
+func (d Definition) CompatibleWithPrior(id ID) bool {
+	for _, compatibleID := range d.CompatiblePriorIDs {
+		if id == compatibleID {
+			return true
+		}
+	}
+	return false
+}
+
+func (d Definition) ModuleIDs() []module.ID {
+	ids := make([]module.ID, 0, len(d.Modules))
+	for _, item := range d.Modules {
+		ids = append(ids, item.ID)
+	}
+	return ids
+}
+
+type ResolveRequest struct {
+	Now        time.Time
+	Location   *time.Location
+	Date       time.Time
+	StormStart time.Time
+	StormEnd   time.Time
+}
+
+type Resolved struct {
+	Definition  Definition
+	GeneratedAt time.Time
+	Timezone    string
+	ValidPeriod timeutil.Period
+}
+
+type Metadata struct {
+	RunID       string          `json:"runId"`
+	ReportID    ID              `json:"reportId"`
+	PromptID    string          `json:"promptId"`
+	GeneratedAt time.Time       `json:"generatedAt"`
+	Timezone    string          `json:"timezone"`
+	ValidPeriod timeutil.Period `json:"validPeriod"`
+}
+
+func (r Resolved) Metadata() Metadata {
+	return Metadata{
+		RunID:       r.GeneratedAt.UTC().Format("20060102T150405.000000000Z") + "_" + string(r.Definition.ID),
+		ReportID:    r.Definition.ID,
+		PromptID:    r.Definition.PromptID,
+		GeneratedAt: r.GeneratedAt,
+		Timezone:    r.Timezone,
+		ValidPeriod: r.ValidPeriod,
+	}
+}