gum is an open-source command-line tool by Rasty Turek (GitHub user ehmo) that gives AI agents and people a safer way to call Google APIs. It is a single binary that runs as a terminal CLI and as an MCP server; MCP, the Model Context Protocol, is a standard way for AI agents to connect to outside tools.
gum carries an embedded catalog of Google API operations (228 operations across 33 services in version 2.3.1), including Gmail, Drive, Docs, Sheets, Calendar, YouTube, Search Console and Google Ads; bundled plugins add Google Trends, Flights, Scholar and Patents. An agent searches the catalog and loads only the operation it needs, instead of a long list of every method. For sign-in, the user registers a Desktop OAuth client from a Google Cloud project, and gum keeps the resulting refresh token in the operating system's keychain, so tokens never appear in prompts. Write and delete calls pass confirmation gates, and large JSON responses are cut down to small results. A setup command installs it for Codex, Claude, Cursor or Gemini.
It is free software under the MIT license and installs with Homebrew.