manage-extensions Guide Skill

This skill allows Tars to manage Gemini CLI extensions — listing, enabling, disabling, and installing them.

How It Works

Extensions are managed via the gemini extensions CLI commands. Because Tars spawns a fresh gemini chat process for each interaction, any changes made during one message take effect on the next message automatically.

Extension enablement state is persisted in: ~/.tars/.gemini/extensions/extension-enablement.json

Commands

All commands below should be executed via run_shell_command. The GEMINI_CLI_HOME environment variable is already set in your shell environment.

List Extensions

bash

gemini extensions list

Shows all installed extensions, their enabled/disabled state, and their MCP servers.

Disable an Extension

bash

gemini extensions disable <name>

Disables the extension for the current user scope. It will no longer load on the next interaction.

•--scope user — Disable for the user (default).
•--scope workspace — Disable only for the current project.

Enable an Extension

bash

gemini extensions enable <name>

Re-enables a previously disabled extension.

Install an Extension

bash

gemini extensions install <path-or-url>

Installs a new extension from a local directory or remote URL.

Link an Extension (Development)

bash

gemini extensions link <path>

Creates a symlink to a local extension directory. Changes to the source are reflected immediately without reinstalling.

Important Notes

•Changes are deferred: Enable/disable only takes effect on the next gemini chat invocation. Since Tars spawns a fresh process per Discord message, changes apply on the next message.
•State file: The enablement state is stored in extension-enablement.json, not in settings.json.
•Scope: Use --scope workspace if you only want to toggle an extension for a specific project context.
•Discovery: If an extension's MCP server fails to connect at startup, it will show an error in the logs but won't crash the session.