github-actions-validator

A validator for GitHub Actions workflows, the YAML files that automate tasks such as testing, building, and deploying code on GitHub.

In plain words
What is it for?
Use it to check files in .github/workflows, debug actionlint findings, test workflows locally, validate custom actions, and review public action versions or deprecations.
Why use it?
It finds syntax errors, configuration problems, invalid actions, and workflow issues before they cause failures on GitHub. It can also test workflows locally with act when available.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/akin-ozer/cc-devops-skills/github-actions-validator
Any agent
npx skills add akin-ozer/cc-devops-skills --skill github-actions-validator
Clone the repo
git clone --depth 1 https://github.com/akin-ozer/cc-devops-skills

Made for: Claude Code, Codex.

Per session 20 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,739 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00020 $0.04739
Opus 5 $0.00010 $0.02370
Sonnet 5 $0.00004 $0.00948
Haiku 4.5 $0.00002 $0.00474

Measured 2d ago against content hash aa9fa15e70ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

github-actions-validator scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

The scan reads SKILL.md. This mod also ships 3 executable files (scripts/install_tools.sh, scripts/validate_workflow.sh, tests/test_validate_workflow.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

devops-skills-plugin/skills/github-actions-validator/SKILL.md · 574 lines

How it starts

The opening of the file, as written. The whole thing — 574 lines — stays where its author put it; the contents beside it link to each section on GitHub.

GitHub Actions Validator

Overview

Validate and test GitHub Actions workflows, custom actions, and public actions using industry-standard tools (actionlint and act). This skill provides comprehensive validation including syntax checking, static analysis, local workflow execution testing, and action verification with version-aware documentation lookup.

Trigger Phrases

Use this skill when the request includes phrases like:

  • "validate this GitHub Actions workflow"
  • "check my .github/workflows/*.yml file"
  • "debug actionlint errors"
  • "test this workflow locally with act"
  • "verify GitHub Action versions or deprecations"

When to Use This Skill

Use this skill when:

  • Validating workflow files: Checking .github/workflows/*.yml for syntax errors and best practices
  • Testing workflows locally: Running workflows with act before pushing to GitHub
  • Debugging workflow failures: Identifying issues in workflow configuration
  • Validating custom actions: Checking composite, Docker, or JavaScript actions
  • Verifying public actions: Validating usage of actions from GitHub Marketplace
  • Pre-commit validation: Ensuring workflows are valid before committing

Required Execution Flow

Every validation run should follow these steps in order.

Step 1: Set Skill Path and Run Validation

Run commands from the repository root that contains .github/workflows/.

SKILL_DIR="devops-skills-plugin/skills/github-actions-validator"
bash "$SKILL_DIR/scripts/validate_workflow.sh" <workflow-file-or-directory>

Step 2: Map Each Error to a Reference

For each actionlint/act error, consult the mapping table below, then extract the matching fix pattern.

Step 3: Apply Minimal-Quote Policy

For each issue:

  1. Include the exact error line from tool output.
  2. Quote only the smallest useful snippet from references/ (prefer <=8 lines).
  3. Paraphrase the rest and cite the source file/section.
  4. Show corrected workflow code.

Step 4: Handle Unmapped Errors Explicitly

Read the full file on GitHub · 574 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 574 lines · 20 tokens per session scan A aa9fa15e70ef

Subscribe to this mod's changes

github-actions-validator is a skill published in the GitHub repository akin-ozer/cc-devops-skills (303 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 20 tokens to every session and 4,739 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

multi-agent-release-manager

Cleans up the workspace, formats code, runs presubmit checks, and uploads CLs to Gerrit.

chromium/chromium · 27 tokens

dsh-web-pre-push-checks

Use before pushing, opening or updating a pull request, or claiming dsh-web checks pass. Selects the required repository gates and diff-specific generation, build, and GUI evidence.

zhu1090093659/dsh-web · 45 tokens

babysit

Same-session monitoring loop for PRs, CI runs, tickets, and deployments using the monitorstart / monitorupdate / autonudgestop MCP tools. The loop re-injects your check instructions into THIS session on an idle interval — same context, same tools — and works from dashboard chat, Slack threads, and Discord DMs. Use…

kirodotdev/KiroCrew · 137 tokens

azsdk-common-pipeline-analysis

Analyze Azure SDK CI/CD pipeline failures into a structured diagnosis, and define the required output format. Load this skill before calling azsdkanalyzepipeline, which returns raw failure data that this skill interprets and formats. USE FOR: "pipeline failed", "build failure", "CI check failing", "tests failing in…

Azure/azure-sdk-for-net · 192 tokens

harness-setup

HAR: Project init, tool setup, agent config, memory setup, skill mirror sync. Trigger: setup, init, new project, CI/Codex setup, harness-mem, mirror. Do NOT load for: implementation, review, release, planning.

Chachamaru127/claude-code-harness · 57 tokens

managing-github-actions-secrets

Creates and updates GitHub Actions secrets for PostHog workflows. Use when adding a new CI secret, rotating an existing secret, wiring a workflow to an API token, package registry credential, deploy key, or any value referenced via ${{ secrets. }} in .github/workflows/.

PostHog/posthog-foss · 67 tokens