# Stage: analyze

## Purpose

Execute selected configured Scriptorium artifacts in dependency order and materialize outputs.

## Inputs

- configured artifacts from `pipeline.scriptorium.artifacts`
- optional selected artifact keys supplied through the stage environment
- built-in, configured, extraction, and previous-session source references in
  artifact inputs

Supported source families:
- built-ins: `narratio.transcript.*`, `narratio.bounds.session`
- prepared stable inputs: `narratio.input.players`, `narratio.input.party`,
  `narratio.input.glossary`
- configured artifacts: `narratio.artifact.<key>`
- extraction lanes: `narratio.extraction.<key>`
- previous-session cache: `narratio.previous_session.artifact.<key>`

## Outputs

- one materialized output per executed configured artifact (`output_path`)
- stage metadata describing selected/generated/reused artifacts

## Key Behavior

- when Scriptorium is absent or no configured artifact is executable, completes
  successfully with no outputs and records explanatory metadata. This is not an
  explicit self-skip: both manifests record success, satisfy publish's
  prerequisite, and an ordinary later run reuses the result until forced.
- builds a runtime artifact catalog containing built-ins, configured artifacts,
  and configured extraction lanes. Extraction availability is hydrated only
  from compatible successful extraction evidence.
- uses enabled configured artifacts by default. An explicit `--artifacts`
  selection is a one-invocation override: it makes exactly the named configured
  artifacts executable even when disabled, and does not automatically include
  dependencies. A selected artifact's dependencies must instead already be
  available to the catalog.
- marks non-executable configured artifacts as reusable when output files already exist.
- validates selected artifact dependency order (cycle-safe topo ordering).
- resolves required/optional inputs per artifact source definition.
- omits an unavailable optional input; an unavailable required input fails.
- resolves prepared stable input sources from `inputs/*.yml` materialized by `prepare`.
- resolves previous-session sources from local `previous/` cache only.
- runs optional render-debug, then artifact execution.
- validates non-empty output files and materializes canonical outputs.

## Failure Semantics

- required missing configured/previous-session inputs fail.
- missing required prepared stable input source includes prepare rerun guidance.
- missing required previous-session source includes prepare rerun guidance.
- missing required `narratio.transcript.final_markdown` or
  `narratio.transcript.final_trimmed_markdown` inputs includes render rerun
  guidance.
- dependency cycles or unavailable required dependencies fail.
- adapter validation failures fail stage.

## Invariants

- `analyze` performs no remote storage calls for previous-session source resolution.
- output provenance and metadata are deterministic per execution.

## Related Contracts And Tests

- [Configuration](../config.md#scriptorium-artifact-entries) owns artifact
  fields and source-selection rules.
- [CLI](../cli.md) owns user-visible artifact selection.
- [Scriptorium](../integrations/scriptorium.md) owns the subprocess contract.
- Implementation and tests: `internal/stage/analyze.go`,
  `internal/stage/analyze_test.go`