Validate exactly one implemented phase or scoped change against its authoritative contract. Use after implementation to re-derive criterion-level conclusions from current evidence and fix only required implementation gaps.
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---
name: phase-validate
description: Validate exactly one implemented phase or scoped change against its authoritative contract. Use after implementation to re-derive criterion-level conclusions from current evidence and fix only required implementation gaps.
---
# Phase Validation
Own contract validation between implementation and structural review.
## Workflow
1. Read the authoritative contract and applicable repository rules unconditionally.
2. Enumerate each observable acceptance criterion, invariant, required progress, environmental assumption, and failure case, then map it to implementation and evidence.
3. Inspect changed files, tests, failure paths, cleanup, side effects, and required checks without trusting implementation claims. Evidence verifies a criterion only when it would fail if the criterion were not met: a test that passes both before and after the change does not verify new behavior. Confirm that each evidence method covers the relevant inputs, states, ordering, and failures.
4. Invoke a focused review skill only when its trigger applies. Treat its findings as claims: verify each one from evidence, and do not treat agreement between reviewers as proof. Keep any fixes within this phase's authority.
5. Use `plan-update` or `spec-update` when the contract is incorrect or incomplete. Do not invent behavior.
6. Fix only implementation gaps required by the selected contract.
7. Run focused checks while correcting, then run the authoritative required command once against final content.
For every criterion report `VERIFIED`, `NOT VERIFIED`, or `INCONCLUSIVE`, with the evidence and a one-sentence explanation. Independence means fresh evidence-based conclusions, not mandatory separate-agent execution.
Do not add verification dependencies or harnesses without authority; report the expected benefit and residual risk when they are unavailable. Do not perform broad maintainability refactoring, final closeout, shipping, commits, pushes, external mutations, or unrelated cleanup. Use `phase-review` after validation for structural regressions.
Finish when every criterion has a supported status, scoped defects are fixed, required checks reflect final content, and blockers are explicit.
