Lint GitHub Actions workflows before CI runs with actionlint

Validate workflow syntax, expressions, and shell steps before broken GitHub Actions changes reach CI.

Prerequisites

actionlint binary and GitHub Actions workflow files

Installation

Use the upstream install or setup path that matches your environment:

• go install github.com/rhysd/actionlint/cmd/actionlint@latest

Requirements and caveats from upstream:

• uses: actions/setup-node@v4
• key: ${{ matrix.platform }}-node-${{ hashFiles('**/package-lock.json') }}
• test.yaml:17:11: input "node_version" is not defined in action "actions/setup-node@v4". available inputs are "always-auth", "architecture", "cache", "cache-dependency-path", "check-latest", "node-version", "node-versi...

Basic usage or getting-started notes:

• Actions usage check to check that inputs at with: and outputs in steps.{id}.outputs are correct

• [shellcheck][] and [pyflakes][] integrations for scripts at run:

• Example of broken workflow:

• Source: https://github.com/rhysd/actionlint

• Extracted from upstream docs: https://raw.githubusercontent.com/rhysd/actionlint/HEAD/README.md

Documentation

• https://github.com/rhysd/actionlint

Source

• Agent Skill Exchange