What problem does it solve? GitHub Actions has three silent-failure behaviours — a non-matching paths: filter publishes no check at all, a skipped job satisfies a required status check, and check-run names carry no workflow prefix — that make naive CI configurations report green without ever running the suite. This Skill provides the reference knowledge needed to add, edit, debug, or review workflows under .github/workflows/ without falling into those traps. ## Core Features & Use Cases - Gate pattern reference: Explains the unskippable gate job with if: always(), its required/optional guard manifest, and the anti-vacuity lock that re-reads the jobs API to certify real conclusions. - Scope derivation: Documents e2e-affected.mjs and its --roots, --self, --only-paths, and --kind flags, including fail-safe directions and the version-skew wrapper requirement. - Sixteen pinnable checks: Lists every gate and ci.yml job name suitable for the protect-main ruleset, plus the exact gh api procedure for pinning them with integration_id: 15368. - Use Case: When a required check sits at "Expected" forever on a PR, or a lane silently stops running after a workflow edit, use this Skill to diagnose which GitHub behaviour caused it and how the gate/backstop test should be updated. ## Quick Start Ask the assistant to explain why a required check is missing on your pull request or to help you add a new CI lane following the gate pattern.