Document Scriptorium as a Promptkit application

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## Purpose
Adapters translate external inputs into public engine requests and translate
public results or errors back to their interface. They own IO and presentation
mechanics; use-case decisions remain behind the root `scriptorium` facade.
Scriptorium adapters translate executable inputs into Promptkit public requests
and translate Promptkit results or errors back to CLI or HTTP behavior. They
own IO and presentation mechanics, not framework decisions.
External contracts are canonical in the [CLI reference](../cli.md), [HTTP API
reference](../api.md), and [Go package contract](../consumers/pkg-scriptorium.md).
External contracts are canonical in the [CLI reference](../cli.md) and
[HTTP API reference](../api.md). Promptkit's public engine contract is
described by its tagged
[Go consumer guide](https://gitea.maximumdirect.net/eric/promptkit/src/tag/v0.1.0/docs/consumers/pkg-promptkit.md).
## Components And Collaborators
- `cmd/scriptorium` passes process arguments and streams to
`internal/adapter/cli`.
- `internal/adapter/cli` parses commands, resolves application settings through
`internal/config`, constructs the public engine, and owns process output
handling.
- `internal/adapter/http` decodes DTOs, maps them to public run requests,
calls its local public `Runner` interface, and maps public errors and results
to HTTP DTOs.
- The root `scriptorium` package maps its public types and options to internal
collaborators and maps selected internal errors to public sentinels.
- `internal/format` formats public prepared runs for the CLI.
- `internal/adapter/cli` resolves settings through `internal/config`,
constructs `promptkit.Engine`, maps CLI values to `promptkit.RunRequest`,
and owns output files, summaries, and exit codes.
- `internal/adapter/http` strictly decodes request DTOs, maps them to Promptkit
public values, calls its adapter-owned `Runner` interface, and maps results
and errors to HTTP DTOs.
- `internal/format` renders `promptkit.PreparedRun` values as deterministic text
or JSON.
## Wiring Flows
### CLI
The CLI resolves configuration before constructing the public engine. `run`
calls `Engine.Run` with a public request and `render` calls `Engine.Prepare`
with the same request mapping. `serve` constructs the HTTP-owned restricted
artifact reader, injects it with `WithArtifactReader`, passes the resulting
engine directly to the HTTP handler, and starts the server.
`run` calls `promptkit.Engine.Run`; `render` calls
`promptkit.Engine.Prepare`. Both share request mapping for prompt/profile
selection, file inputs, variables, and presence-aware execution overrides.
Omitted framework settings remain zero values so Promptkit resolves its own
defaults.
Parser state records whether numeric runtime values were explicitly supplied.
That presence is carried into `scriptorium.ExecutionTargetOverride`, allowing
the engine to distinguish omitted values from explicit zero overrides.
`serve` constructs Scriptorium's restricted HTTP artifact reader, injects it
with `promptkit.WithArtifactReader`, passes the engine through the HTTP
adapter's consumer-owned `Runner` interface, and starts the server.
### HTTP
The handler first enforces transport limits, strict JSON decoding, and the
minimal request shape. It maps DTO values to public types without deciding
prompt selection, source behavior, or validation semantics. On success it maps
the public result to the response DTO; on failure it uses `errors.Is` over
public framework errors and HTTP-local artifact-policy errors to choose the
public error mapping.
The handler enforces transport limits and strict JSON decoding before mapping
DTOs into `promptkit.RunRequest`, `promptkit.ArtifactRef`, and
`promptkit.ExecutionTargetOverride`. On success it reads Promptkit artifact,
validation, model, usage, and metadata values directly.
The [HTTP API reference](../api.md) owns the route, DTO schema, status codes,
and externally observable limit behavior.
### Public Go Facade
`NewEngine` applies public options, selects filesystem, `fs.FS`, single-file,
or in-memory dependencies, and constructs a runner. The conversion functions
copy maps and slices across the boundary so callers do not receive internal
domain values. The facade maps selected internal errors to the public sentinel
set and keeps direct request API keys out of public results.
Failure mapping uses `errors.Is` against Promptkit's public sentinels and the
HTTP reader's Scriptorium-owned containment and size errors. Wrapped reader
errors preserve their identity through Promptkit's artifact-load boundary.
## Package-Local Guarantees
- Adapters do not embed framework orchestration or source-loading decisions.
- Configuration is resolved before adapter dependency composition.
- CLI and HTTP consume the public engine without a repairer; a repairer remains
available only through explicit internal runner construction.
- DTO conversion preserves explicit numeric-override presence.
- Error mapping matches error identities, not error text.
- No adapter creates durable run state; caller-selected output files are not
application state.
- Adapters contain no copied framework types or orchestration.
- Configuration is resolved before Promptkit engine construction.
- Explicit numeric overrides preserve presence, including zero.
- HTTP DTO and error mapping remains stable and transport-owned.
- Resolved secrets are not serialized or printed.
- No adapter creates durable run state.
## Failure And Verification Boundaries
## Verification
Keep external error payloads concise, preserve strict external decoding, and do
not serialize resolved secret values. Validation content failures remain result
state; runtime failures remain errors for the relevant adapter to map.
Inspect focused tests when changing this area:
Inspect:
- `internal/adapter/cli/run_test.go`
- `internal/adapter/http/handler_test.go`
- `engine_test.go`
- `internal/adapter/http/artifact_reader_test.go`
- `internal/format/prepared_run_test.go`
- `internal/adapter/dependency_test.go`
Run the affected adapter package tests and recheck the relevant canonical
contract. The [testing policy](../policy/testing.md) owns global test
sufficiency guidance.
The adapter tests protect parsing, configuration mapping, output, status
mapping, restricted artifacts, and representative real Promptkit-engine
workflows. The dependency test protects the repository boundary.
## Change Recipes
### Application Configuration Fields
For a CLI or HTTP change:
1. Add the field to the relevant `internal/config` shape and default handling.
2. Parse and validate it, then preserve configuration and CLI-override
precedence while wiring it through its consuming adapter.
3. Add focused configuration and adapter tests for parsing, mapping, and
effective behavior.
4. Update the [configuration contract](../config.md) and any affected external
contract.
1. identify the Scriptorium-owned external contract;
2. map through Promptkit public values without copying framework semantics;
3. add or update the narrow application-owned test;
4. update the canonical Scriptorium contract; and
5. coordinate and tag Promptkit first if a required public capability is
genuinely absent.
### CLI Flags
1. Add the flag to the relevant parser in `internal/adapter/cli/run.go`.
2. Keep command scope and application-configuration precedence intentional.
3. Add or update parser and command tests in
`internal/adapter/cli/run_test.go`.
4. Update the [CLI contract](../cli.md) and affected maintained examples.
### Adapter Capabilities
1. Define or reuse an adapter-local consumer interface with public facade
types when a test seam is needed.
2. Implement translation and IO behavior without moving framework decisions out
of the public engine.
3. Add focused mapping, parsing, and error-behavior tests.
4. Update this document and the affected public or integration contract. Update
[source internals](sources.md) when source-loading behavior changes.
Update [source internals](sources.md) when application source locations or HTTP
artifact containment changes.

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# LLM Internals
## Purpose
`internal/llm` defines the provider-neutral `Client` interface and the
OpenAI-compatible client implementation. The [OpenAI-compatible integration
contract](../integrations/openai-compatible-chat.md) owns the outbound HTTP wire
format and protocol behavior.
## Construction
`NewOpenAICompatibleClient` validates a non-empty configured base URL, records
an optional default model, and resolves one transport cap. A supplied client
with a positive timeout supplies that cap; otherwise a positive configured
timeout is used, then the internal default.
When callers supply an `http.Client`, construction clones it rather than
mutating the caller's instance. A supplied client with a zero or negative
timeout receives the resolved transport cap in the clone. The client stores the
trimmed base URL, default model, and cloned client.
## Generate Flow
`Generate` receives a `domain.GenerateRequest` from the runner:
1. validate the effective timeout and choose the request endpoint;
2. map the domain request to the internal wire-request representation;
3. validate and flatten extra parameters and encode JSON;
4. derive a child context when the effective generation timeout is positive,
then create the HTTP request with that context;
5. prefer a direct API key, otherwise resolve the configured key environment
variable;
6. execute with the construction-time HTTP client, reject non-success status
responses without returning
provider response bodies; and
7. decode the response subset into `domain.GenerateResponse`.
`openAIChatRequestFromGenerateRequest` is the conversion boundary for effective
model defaults, explicit numeric-presence state, rendered messages, structured
output, and session-ID validation. `openAIChatRequestPayload` protects reserved
fields and JSON encoding before an HTTP call. The external payload shape is
defined only in the [integration contract](../integrations/openai-compatible-chat.md).
## Error Categories
The package uses these internal sentinels:
- `ErrInvalidConfig` for invalid client construction;
- `ErrInvalidRequest` for invalid effective generation input;
- `ErrRequestFailed` for request construction or transport failures;
- `ErrUnexpectedStatus` for non-success HTTP responses; and
- `ErrMalformedResponse` for invalid or incomplete successful-response data.
The runner maps an invalid LLM request to its invalid-request category and
other LLM failures to its generation category. Adapters then apply their public
error contracts.
## Package-Local Guarantees
- The default-model fallback happens before wire encoding.
- Per-generation timeout handling derives a request context; it never replaces
or mutates the configured HTTP client's transport cap.
- Direct API keys take precedence over environment lookup within this client.
- Provider response bodies are discarded for non-success status responses.
- The client does not implement retries, tool calls, or a stateful session
store.
## Verification And Change Recipe
Inspect:
- `internal/llm/openai_compatible_client_test.go`
- `internal/usecase/runner_test.go`
- `internal/adapter/http/handler_test.go`
When changing the client:
1. keep domain-to-wire mapping inside `internal/llm` and preserve the `Client`
interface;
2. test construction, timeout selection, mapping, and error categorization;
3. update the [OpenAI-compatible integration contract](../integrations/openai-compatible-chat.md)
for any observable wire or protocol change; and
4. update [runner internals](runner.md) if the client boundary or structured
output handoff changes.
The [testing policy](../policy/testing.md) owns global test sufficiency.

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# Internal Component Overview
## Purpose
This is the inventory of Scriptorium's implemented components for contributors.
The [architecture policy](../policy/architecture.md) owns normative boundaries
and invariants; public behavior belongs in the linked contracts.
## Public And Command Entrypoints
This is the complete inventory of Scriptorium's implemented Go components.
The [architecture policy](../policy/architecture.md) owns normative boundaries;
public behavior belongs in the linked contracts.
| Component | Implemented responsibility | References |
| --- | --- | --- |
| Root package `scriptorium` | Public Go facade that constructs the engine, exposes request/result types and options, and maps internal errors. | [Go package contract](../consumers/pkg-scriptorium.md), [adapter internals](adapters.md) |
| `cmd/scriptorium` | Process entrypoint that delegates command execution to the CLI adapter. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
| `cmd/scriptorium` | Process entrypoint that delegates arguments and streams to the CLI adapter. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
| `internal/adapter/cli` | Parses commands, resolves application settings, constructs Promptkit engines, maps requests, and owns process output and exit behavior. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
| `internal/adapter/http` | Owns routes, DTOs, strict decoding, limits, Promptkit request/result mapping, public error mapping, and restricted HTTP artifact reading. | [HTTP API](../api.md), [adapter internals](adapters.md), [source internals](sources.md) |
| `internal/config` | Discovers and strictly decodes application configuration and applies built-in and CLI precedence. | [configuration contract](../config.md), [adapter internals](adapters.md) |
| `internal/defaults` | Holds Scriptorium-owned application and HTTP defaults. | [configuration contract](../config.md) |
| `internal/format` | Formats Promptkit prepared-run values for CLI text or JSON output. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
## Adapters, Domain, And Use Case
| Component | Implemented responsibility | References |
| --- | --- | --- |
| `internal/adapter/cli` | Parses CLI commands, constructs the public engine from application settings, and handles process input and output. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
| `internal/adapter/http` | Maps HTTP requests and responses through public engine values, maps public errors, and owns restricted HTTP artifact policy. | [HTTP API contract](../api.md), [adapter internals](adapters.md) |
| `internal/domain` | Defines core request, result, output-contract, and LLM-boundary types. | [runner internals](runner.md) |
| `internal/usecase` | Implements `Runner` preparation, execution, validation coordination, and the repairer boundary. | [runner internals](runner.md) |
## Configuration And Sources
| Component | Implemented responsibility | References |
| --- | --- | --- |
| `internal/config` | Loads application settings, applies defaults, and applies CLI overrides. | [configuration contract](../config.md), [adapter internals](adapters.md) |
| `internal/defaults` | Holds compile-time default values used when application settings are resolved. | [configuration contract](../config.md) |
| `internal/promptdef` | Loads prompt definitions from filesystem and `fs.FS` sources. | [configuration contract](../config.md), [source internals](sources.md) |
| `internal/profile` | Loads filesystem and `fs.FS` execution profiles and combines profile repositories. | [configuration contract](../config.md), [source internals](sources.md) |
| `internal/profile/builtin` | Provides embedded built-in execution profiles as a repository. | [configuration contract](../config.md), [source internals](sources.md) |
| `internal/filecatalog` | Provides shared YAML discovery and source-root helpers. | [source internals](sources.md) |
| `internal/artifact` | Provides the framework's ordinary inline and unrestricted file artifact reader. | [configuration contract](../config.md), [source internals](sources.md) |
| `internal/prompt` | Renders prompt templates into messages. | [runner internals](runner.md) |
## Formatting, Validation, And Model Access
| Component | Implemented responsibility | References |
| --- | --- | --- |
| `internal/format` | Formats public prepared-run information for CLI output. | [CLI contract](../cli.md), [adapter internals](adapters.md) |
| `internal/validate` | Defines validation interfaces and provides standard filesystem and `fs.FS` schema validation. | [configuration contract](../config.md), [source internals](sources.md), [runner internals](runner.md) |
| `internal/llm` | Defines the provider-neutral LLM client boundary and its OpenAI-compatible implementation. | [OpenAI-compatible integration](../integrations/openai-compatible-chat.md), [LLM internals](llm.md), [runner internals](runner.md) |
Focused internal documents describe the components that have detailed
orchestration, adapter, or source behavior. Package tests live alongside the
implementation and are identified in those focused documents where relevant.
Framework implementation packages are provided by
[Promptkit v0.1.0](https://gitea.maximumdirect.net/eric/promptkit/src/tag/v0.1.0/docs/consumers/pkg-promptkit.md)
and are not part of this repository.

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# Runner Internals
## Purpose
`internal/usecase.Runner` is the prompt-execution orchestrator. It prepares
domain requests, invokes an injected LLM client, validates output, and returns
domain results. Transport parsing, response mapping, and public type conversion
remain outside this package.
The [configuration reference](../config.md) owns prompt, profile, schema, and
runtime-setting definitions. Public error behavior is defined by the
[HTTP API](../api.md) and [Go package](../consumers/pkg-scriptorium.md)
contracts.
## Dependencies And Construction
`Runner` receives these collaborators:
- `promptdef.Repository`;
- `profile.Repository`;
- `artifact.Reader`;
- `prompt.Renderer`;
- `llm.Client`;
- `validate.Validator`; and
- an optional `OutputRepairer`.
`NewRunner` constructs a runner without a repairer. `NewRunnerWithRepairer`
accepts one explicitly. The public engine chooses concrete repositories and
readers; executable adapters reach the runner only through that engine. The
runner does not load application configuration.
## Prepare Flow
`Prepare` performs one deterministic preparation pass for a request:
1. validate the prompt ID and load the prompt definition;
2. hash the definition and select the explicit or default profile;
3. load the profile and resolve effective execution settings;
4. validate endpoint, model, and credential availability;
5. resolve the output contract and, for JSON Schema output, load a structured
schema document before model execution;
6. read and hash input artifacts;
7. render messages and the session ID; and
8. return a `PreparedRun` containing the effective state and rendered-prompt
hash.
Execution settings merge defaults, profile values, and a request override.
Numeric override presence is retained so explicit zero values are not confused
with omissions.
## Run And Validation Flow
`Run` creates a run ID and timestamps, then calls `Prepare` rather than
duplicating preparation. It sends the prepared prompt, effective target,
target-presence state, and optional structured-output specification to the LLM
client. It converts the returned content to an output artifact, validates it,
and returns the artifact, validation, hashes, usage, and timing metadata.
A validator can return a content result or an operational error. Content
failures stay in the result; schema loading, compilation, and validator
operational failures are returned as `ErrValidation`. The canonical distinction
for callers is documented by the public contracts.
## Repair Boundary
Repair is an internal optional loop. It starts only when a repairer is present,
the output contract permits one or more attempts, validation failed, and the
validation mode is JSON or JSON Schema. Each repair receives the previous
output, validation errors, effective target, structured-output specification,
and attempt metadata; every repaired result is validated again.
`NewDefaultOutputRepairer` delegates to the injected LLM client. The public
engine, and therefore CLI and HTTP, uses `NewRunner` and does not inject this
repairer.
## Error Translation
Runner sentinels identify failure categories for adapters:
- `ErrInvalidRequest`
- `ErrProfileRequired`
- `ErrAPIKeyEnvMissing` and `ErrAPIKeyRequired`
- `ErrPromptLoad`, `ErrProfileLoad`, and `ErrArtifactLoad`
- `ErrPromptRender`
- `ErrLLMGenerate`
- `ErrValidation`
Wrap errors with those sentinels and preserve their identities through
`errors.Is`; adapters must not classify errors by message text. The runner
passes direct keys only to the LLM boundary and never includes resolved key
values in prepared or run results.
## Package-Local Guarantees
- `Run` always reuses `Prepare`.
- Schema documents are loaded before the initial LLM call when structured output
is required.
- Output validation records attempts used, including repair attempts.
- Runner state is per request; the package does not create a durable run store
or manifest.
- Source, renderer, validator, and LLM implementations remain injected
boundaries.
## Verification And Change Recipe
Inspect:
- `internal/usecase/runner_test.go`
- `engine_test.go`
When changing orchestration:
1. identify the collaborator boundary and the affected `Prepare` or `Run` state;
2. preserve the `Run`-through-`Prepare` path and error identity;
3. add focused runner or integration tests for changed state transitions,
validation, or repair behavior; and
4. update the owning external contract and any affected source or LLM internal
document.
The [testing policy](../policy/testing.md) owns global test sufficiency.

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## Purpose
This document describes how source packages load prompt definitions, profiles,
schemas, and artifacts. The [configuration reference](../config.md) owns their
user-facing formats and settings. The [HTTP API reference](../api.md) owns
HTTP-visible artifact outcomes; [operations](../operations.md) owns deployment
handling.
This document covers Scriptorium-owned source locations and the restricted HTTP
artifact reader. Prompt, profile, schema, and ordinary artifact semantics are
owned by the tagged
[Promptkit format reference](https://gitea.maximumdirect.net/eric/promptkit/src/tag/v0.1.0/docs/formats.md).
## Prompt Definitions
## Application Source Locations
`internal/promptdef` provides filesystem and `fs.FS` repositories. Both use
`internal/filecatalog` for recursive YAML discovery, deterministic ordering,
display paths, and root cleaning.
`internal/config` resolves `prompt_dir`, `profile_dir`, and `schema_dir` from
Scriptorium defaults, configuration files, and CLI overrides.
`internal/adapter/cli` passes those paths into `promptkit.Config` when
constructing the engine.
Repositories select a prompt by YAML ID and optional version rather than by
path. They decode through strict YAML handling, reject duplicate matching
definitions, and resolve `content_file` relative to the definition. The `fs.FS`
implementation resolves content paths inside its source root; absolute paths and
traversal outside that root are rejected before file access.
Scriptorium does not search, parse, validate, or overlay framework source files
itself. Promptkit owns prompt selection, profile built-ins and overlays, schema
resolution, ordinary file artifacts, and the related error identities.
## Profiles And Built-Ins
The [configuration reference](../config.md) owns Scriptorium's source-location
fields and precedence. Maintained files under `examples/` are application
inputs that use Promptkit's tagged formats.
`internal/profile` provides filesystem, `fs.FS`, and overlay repositories.
`internal/profile/builtin` exposes embedded assets through the same repository
interface.
## Restricted HTTP Artifact Reader
An overlay asks its primary source first. It falls back only when the primary
reports `ErrProfileNotFound`; invalid YAML, duplicate IDs, validation failures,
and raw-key failures are returned rather than hidden by fallback. This makes a
custom ID override a built-in ID while retaining errors in the custom source.
`internal/adapter/http` implements `promptkit.ArtifactReader` for HTTP
requests. The `serve` path injects it with
`promptkit.WithArtifactReader`, replacing Promptkit's ordinary reader for
inbound HTTP inputs.
The public engine can overlay in-memory profiles ahead of both file-backed and
built-in repositories. Profile field definitions, validation ranges, and the
built-in catalog remain in the [configuration reference](../config.md).
The reader:
## Schemas
- accepts inline references without an artifact root;
- denies file references when no root is configured;
- resolves relative paths below the configured root;
- accepts absolute paths only when they are lexically within that root;
- rejects lexical traversal outside the root;
- applies the configured file byte limit, with zero meaning unlimited;
- preserves content type, body, size, hash, name, and URI metadata; and
- honors context cancellation.
`internal/validate` supplies `StandardValidator` for filesystem sources and
`FSValidator` for `fs.FS` sources. Directory-backed validation loads the named
schema path; it does not search directories by basename. `fs.FS` schema paths
are cleaned and checked against their configured root, while a single-file
source matches its file base name.
Containment is lexical and does not resolve symlinks. The operating system
follows symlinks after the check. The [HTTP API](../api.md) owns observable
request outcomes, and [operations](../operations.md) owns safe deployment
permissions and root selection.
The runner requests a schema document before generation when it needs
structured output. JSON and schema mismatches in generated content are
validation results; source access, decoding, registration, and compilation
failures are operational errors.
## Artifacts
`internal/artifact` owns the framework's ordinary inline and unrestricted file
reader. The public engine uses it by default and permits consumers to replace it
for every input through the public `ArtifactReader` extension. The
HTTP adapter owns its restricted reader for HTTP containment: `serve` injects
that reader into the public engine with `WithArtifactReader`.
The rooted reader cleans paths and applies lexical containment without resolving
symlinks. It checks relative references against the configured root and accepts
absolute references only when they remain inside that lexical root. The OS still
follows symlinks after that check. The public containment outcome is documented
by the [HTTP API reference](../api.md); deployment permissions belong in
[operations](../operations.md).
## Failure Boundaries
Source packages report repository, decoding, duplicate, validation, and read
failures to their callers. They do not select public status codes or response
schemas. The runner categorizes source failures and the public engine preserves
the corresponding public error identities; adapters map those identities to
their own external contract.
Source reads use current filesystem or `fs.FS` content for each request. These
packages create no manifests, checkpoints, or durable run state.
Reader errors remain identifiable after Promptkit wraps them as artifact-load
failures, allowing the HTTP adapter to preserve Scriptorium status and error
codes.
## Verification And Change Recipe
Inspect:
- `internal/promptdef/repository_test.go`
- `internal/profile/repository_test.go`
- `internal/profile/builtin/repository_test.go`
- `internal/artifact/reader_test.go`
- `internal/config/config_test.go`
- `internal/adapter/cli/run_test.go`
- `internal/adapter/http/artifact_reader_test.go`
- `internal/validate/standard_validator_test.go`
- `engine_test.go`
- `internal/adapter/http/handler_test.go`
When updating prompt, profile, schema, or built-in assets:
When changing an application source location or HTTP artifact policy:
1. keep assets valid for the strict loader and the relevant source boundary;
2. update the [configuration reference](../config.md) when a file-format,
catalog, or default changes;
3. run focused source and integration tests, including the built-in repository
test when embedded assets change; and
4. update this document when discovery, precedence, containment, or failure
mechanics change.
The [testing policy](../policy/testing.md) owns global test sufficiency.
1. preserve strict configuration precedence and the Promptkit public boundary;
2. keep containment and size policy in Scriptorium;
3. update focused configuration, reader, and handler tests;
4. update the [configuration](../config.md), [HTTP](../api.md), and
[operations](../operations.md) contracts as applicable; and
5. do not duplicate Promptkit loaders, formats, or ordinary artifact behavior.