github-actionslisted
Install: claude install-skill toddkasper/expert-skills
# GitHub Actions — Skills Reference
## Overview
**This file is an operational playbook, not an exam outline.** Each section states the rules an agent must apply when building or reviewing Actions automation: syntax constraints, security invariants, decision criteria, and anti-patterns to catch in review. Benchmarked against the GitHub Actions (GH-200) certification blueprint.
> **Load this skill when…** authoring or reviewing GitHub Actions workflow YAML; designing reusable workflows, composite actions, or custom JS/Docker actions; configuring self-hosted runners, OIDC cloud auth, or enterprise runner/policy governance; or hardening an Actions pipeline against script-injection and supply-chain risks.
> **Not this skill:** general Git/GitHub repository administration, branch protection without Actions, or application code in the repository.
> **Study resources, domain weights, and credential logistics:** [references/study-resources.md](references/study-resources.md).
> **Verify steps assume nothing about your tooling** — use your project's MCP/automation, the GitHub CLI (`gh`) and Actions log/`act`/workflow-lint, or the GitHub web UI, in that order of preference.
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## Uncertainty & Escalation
- **Always re-verify live — volatile facts:** GitHub-hosted runner image versions and pre-installed software (`ubuntu-latest`, `windows-latest`, `macos-latest` image mappings change on a rolling basis) `[volatile — verify live]`, action SHA pins for commonly-used actions (e.g.,