Act vs GitHub CLI

act is an open-source command-line tool that runs GitHub Actions workflows locally using Docker containers. It reads workflow files from .github/workflows/ and executes them with environment variables and filesystem configurations matching GitHub's hosted runners. The tool enables fast local feedback on workflow changes without requiring commits and pushes to a remote repository.

GitHub CLI is a developer-utilities tool that official command-line tool for github that brings pull requests, issues, and workflows to the terminal. It is open source software.