Summary

• stop default codex review from passing a positional prompt together with --base, which Codex CLI 0.130.0+ rejects
• keep plain diff reviews on native codex review base-branch mode and route custom-instruction reviews through codex exec with an explicit git diff against the base branch
• regenerate the affected skill docs and refresh golden baselines/tests so the incompatibility stays covered

Testing

• bun run gen:skill-docs --host all
• bun test test/gen-skill-docs.test.ts test/skill-validation.test.ts test/host-config.test.ts

Closes #1428