actionlint is a static analysis tool and linter specifically designed for GitHub Actions workflow files. It functions as a CI workflow validator and YAML configuration linter to ensure the syntax and logic of automation files are correct before deployment.
The project distinguishes itself by performing deep security auditing and script analysis. It includes a shell script auditor to detect syntax bugs and script injection vulnerabilities in inline commands, and it scans for hardcoded credentials to prevent security leaks.
The tool covers a broad range of validation capabilities, including expression type checking, job dependency verification, and the validation of reusable workflows and matrix configurations. It also verifies trigger events, cron schedules, and action metadata to ensure compatible data types and required parameters are present.
The linter can be used via the command line or integrated into IDEs for real-time feedback.