Validate Tests (Codex Gate)

Gate the test plan of an implementation plan before any implementation starts. Combines a local check against the testing guidelines with an external Codex review, following the shared convention in ../_shared/CODEX_GATE.md.

This is a required step between /create-plan and /implement. Once the plan passes this gate, the test plan is authoritative — /implement treats it as immutable.

Instructions

1. Find the Plan

   • Detect current workflow folder from git branch
   • Read .ai/<folder>/plan.md
   • If no plan exists, suggest running /create-plan first

2. Local Validation

   Load TESTING_GUIDELINES.md and GIT_TEST_SCENARIOS.md, then check the Test Plan section:

   • Each scenario follows the guidelines (setup patterns, assertions that verify behavior rather than just "no error", proper Git scenario setup)
   • Pay special attention to rules marked CRITICAL in the guidelines
   • All code paths, error conditions, and edge cases have scenarios
   • Scenarios are concrete enough to implement without guessing

   Fix what you find directly in the plan.

3. Codex Gate

   Run a Codex gate per ../_shared/CODEX_GATE.md:

   • Artifact: the Test Plan section of .ai/<folder>/plan.md
   • Task for Codex: find missing scenarios, wrong or underspecified expected outcomes, and scenarios that don't match the source of truth. TDD framing: these tests define the design — gaps found now are cheap, gaps found during implementation are expensive
   • Source of truth: the spec issue or analysis.md/concept.md the plan was created from (pass its content or path)
   • Guidelines: TESTING_GUIDELINES.md, GIT_TEST_SCENARIOS.md

4. Evaluate and Apply

   Evaluate every Codex finding per the convention: apply only with high confidence, reject over-engineering and hypothetical scenarios, when in doubt leave it out. Update the plan's Test Plan section with applied findings.

   Log all findings — applied, partial, and rejected with reasons — to .ai/<folder>/codex-test-plan.md.

5. Report Findings

   Summarize:

   • Local validation: issues found and fixed
   • Codex gate: findings applied / rejected (with the log path)
   • Open questions that need the user (genuine design decisions only)
   • Confirmation that the plan is gated and ready for /implement