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pantheon-ai/github-actions-validator

Comprehensive toolkit for validating, linting, and testing GitHub Actions workflow files, custom local actions, and public actions. Use this skill when working with GitHub Actions YAML files (.github/workflows/*.yml), validating workflow syntax, testing workflow execution with act, or debugging workflow issues.

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action_versions.mdreferences/

Action Version Validation Reference

This reference provides current recommended action versions and validation procedures for GitHub Actions workflows.

Current Recommended Versions (December 2025)

ActionCurrent VersionMinimum SupportedNotes
actions/checkoutv6v4v6 stores credentials in $RUNNER_TEMP
actions/setup-nodev6v4v6 adds Node 24 support
actions/setup-pythonv5v4v5 adds Python 3.13 support
actions/setup-javav4v4Current latest
actions/setup-gov5v4v5 adds Go 1.23 support
actions/cachev4v4v4.2.0+ required as of Feb 2025
actions/upload-artifactv4v4v3 deprecated
actions/download-artifactv4v4v3 deprecated
docker/setup-buildx-actionv3v3Current latest
docker/login-actionv3v3Current latest
docker/build-push-actionv6v5v6 adds provenance attestation
docker/metadata-actionv5v5Current latest
aws-actions/configure-aws-credentialsv4v4OIDC support improved

Version Validation Process

Step 1: Extract Action References

For each uses: statement in the workflow, extract:

  • Action name (e.g., actions/checkout)
  • Version (e.g., v4, v4.1.1, or SHA like b4ffde65f46...)

Step 2: Compare Against Recommended Versions

For each action found:

  1. Look up the action in the table above
  2. Compare the workflow version against the Current Version
  3. Flag if using a version older than Minimum Supported

Step 3: Report Findings

Generate warnings for:

  • OUTDATED: Action using older major version (e.g., checkout@v4 when v6 is current)
  • DEPRECATED: Action using version below minimum supported
  • UP-TO-DATE: Action using current or acceptable version

Example Version Validation Output

=== Action Version Check ===

actions/checkout@v6.0.0 - UP-TO-DATE (current: v6)
actions/setup-java@v4.2.1 - UP-TO-DATE (current: v4)
docker/build-push-action@v5.3.0 - OUTDATED (current: v6, using: v5)
actions/upload-artifact@v3 - DEPRECATED (minimum: v4, using: v3)

Recommendation: Update docker/build-push-action to v6 for provenance attestation support
Recommendation: Update actions/upload-artifact to v4 (v3 is deprecated)

Using the Version Check Flag

# Check action versions in workflow
bash scripts/validate_workflow.sh --check-versions .github/workflows/ci.yml

# Full validation including version check
bash scripts/validate_workflow.sh .github/workflows/ci.yml

Node.js Runtime Deprecation Timeline

GitHub Actions runtime requirements:

  • Node.js 12: EOL April 2022 - Actions using this are deprecated
  • Node.js 16: EOL September 2023 - Actions using this are deprecated
  • Node.js 20: EOL April 2026 - Current runtime for most actions
  • Node.js 22/24: Current LTS - Newer actions support these

SHA Pinning Best Practice

For security, pin actions to specific commit SHAs:

# Recommended: SHA pinning with version comment
- uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3  # v6.0.0
- uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903  # v6.0.0

# Acceptable: Major version tag
- uses: actions/checkout@v6

# Not recommended: Branch reference
- uses: actions/checkout@main

Cache Storage Updates (November 2025)

GitHub Actions cache storage expanded beyond the 10 GB limit:

New Features:

  • Pay-as-you-go model: Repositories can store more than 10 GB of cache data
  • Free tier: All repositories continue to receive 10 GB at no additional cost
  • New management policies:
    • Cache size eviction limit (GB): Control maximum cache size
    • Cache retention limit (days): Set how long caches are retained

Pricing:

  • First 10 GB per repository: FREE
  • Additional storage: Comparable to Git LFS and Codespaces storage
  • Requires Pro, Team, or Enterprise account to exceed 10 GB limit

Cache best practices:

  • Monitor cache usage in repository settings
  • Configure eviction limits to control costs
  • Use appropriate retention periods for your workflow
  • Clean up old caches regularly
  • Consider cache key strategies to avoid cache bloat

Validation Checklist

When validating workflows, ALWAYS:

  1. Run the validation script
  2. Manually review uses: statements against the version table
  3. Warn about any outdated or deprecated versions
  4. Suggest specific upgrade paths with SHA pinning

Install with Tessl CLI

npx tessl i pantheon-ai/github-actions-validator@0.1.0

SKILL.md

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