## 1. Eval Contract

- [x] 1.1 Extend `DiagnosisEvalCase` with optional V2 audit expectations.
- [x] 1.2 Extend `DiagnosisEvalResult` and report output with observed audit signals.
- [x] 1.3 Add deterministic evaluator checks for Gatekeeper, claim checks, Composer output, and raw JSON leakage.

## 2. Fixtures and Baseline

- [x] 2.1 Add fixed eval cases for Gatekeeper failure, unsupported claim filtering, and Composer fallback leakage prevention.
- [x] 2.2 Add matching trace fixtures for each new case.
- [x] 2.3 Regenerate baseline JSON and Markdown reports.

## 3. Documentation

- [x] 3.1 Update eval README with stage 5 scope and verification commands.
- [x] 3.2 Rewrite eval schema documentation so V2 audit fields and case expectations are readable.

## 4. Verification and Archive

- [x] 4.1 Add or update unit tests for the new V2 audit checks.
- [x] 4.2 Run focused evaluator and agent-chain tests.
- [x] 4.3 Validate and archive the OpenSpec change.
- [x] 4.4 Commit the completed phase 5 changes.