Install and manage extensions
mcp & extensions
// what it does
Extensions bundle MCP servers, custom commands, context files, and tool restrictions into one installable unit. gemini extensions install takes a GitHub URL or a local path and drops it under ~/.gemini/extensions/<name>/. Update with gemini extensions update --all, and toggle per-scope with enable/disable and --scope=workspace.
// shell
$ gemini extensions install https://github.com/gemini-cli-extensions/security$ gemini extensions update --all$ gemini extensions disable security --scope=workspace// gotcha
An extension can register MCP servers that run arbitrary code, so installing one is as much a trust decision as adding an MCP server — read its gemini-extension.json first. Listing installed extensions live is done with /extensions inside a session, not a shell subcommand.