goose MCP Setup: Add Extensions in goose Desktop, the CLI and config.yaml

In goose, every MCP server is an "extension." To add one in goose Desktop, open the sidebar, click Extensions, then Add custom extension. In the CLI, run goose configure, choose Add Extension and follow the prompts. Advanced users can edit ~/.config/goose/config.yaml directly.

goose is the open-source AI agent from Block. Anthropic's AAIF announcement names "goose by Block" as a founding project of the Agentic AI Foundation (AAIF), alongside MCP. Its GitHub repository now sits under the aaif-goose organization. This guide covers all three setup routes, plus the permission setting you should change first.

Checked against: goose's Using Extensions documentation and the goose GitHub repository on 2 November 2026. eSEOspace did not test goose.

Before you start: permissions

goose's docs are direct about this: "goose operates autonomously by default." Combined with its built-in Developer extension, that means goose "can execute commands and modify files without your approval." Before connecting business tools, set goose's permission mode and tool permissions so writes need approval. Our permissions and approvals lesson explains what to aim for.

Option 1: goose Desktop

1. Click the button in the top-left to open the sidebar.
2. Click Extensions.
3. Click Add custom extension.
4. Fill in the form. goose's example for the Knowledge Graph Memory server:
5. Type: Standard IO
6. ID: kgm-mcp (any name you like)
7. Name: Knowledge Graph Memory
8. Command: npx -y @modelcontextprotocol/server-memory
9. Add environment variables with the Add button beside each one.
10. Set a Timeout for tool calls, then click Add.

Use the toggles on the same screen to turn extensions on or off for new sessions.

Option 2: goose CLI

Run:

goose configure

Then choose Add Extension and pick a type:

• Built-In Extension: one that ships with goose.
• Command-Line Extension: a local command, such as npx -y @modelcontextprotocol/server-memory or uvx mcp-wiki.
• Remote Extension (Streamable HTTP): a hosted server URL.

The CLI asks for a name, the command or URL, a timeout and any environment variables. goose's docs note that Java and Kotlin extensions are only supported on Linux and macOS.

To add an extension for one session only, use flags:

goose session --with-extension "uvx mcp-server-fetch"
goose session --with-streamable-http-extension "https://example.com/streamable"

Inside a running session, /extension npx -y @modelcontextprotocol/server-memory adds a stdio extension on the fly.

Option 3: Edit config.yaml

goose's docs show this entry for the GitHub server in ~/.config/goose/config.yaml:

extensions:
  github:
    name: GitHub
    cmd: npx
    args: [-y, @modelcontextprotocol/server-github]
    enabled: true
    envs: { "GITHUB_PERSONAL_ACCESS_TOKEN": "<YOUR_TOKEN>" }
    type: stdio
    timeout: 300

Note the differences from the JSON most clients use: cmd instead of command, envs instead of env, and an explicit type. Checked against goose's docs on 2 November 2026.

A remote server that needs a pre-registered OAuth app looks like this:

extensions:
  remote-example:
    name: Remote Example
    type: streamable_http
    uri: https://example.com/mcp
    client_id: <YOUR_REGISTERED_CLIENT_ID>
    client_secret_key: REMOTE_EXAMPLE_OAUTH_SECRET
    scopes:
      - example.readonly
    enabled: true
    timeout: 300

goose's docs explain that remote extensions normally get a client ID automatically through Client ID Metadata Documents or Dynamic Client Registration. You only set client_id when a server supports neither. client_secret_key names a secret stored in goose, and "the secret value itself never goes in the config file." If you leave out scopes, goose uses the server's advertised scopes, "which may be broader than the extension needs."

Built-in extensions you already have

goose ships with several extensions that are MCP servers in their own right. Its docs list Developer (on by default), Computer Controller, Memory, Tutorial and Auto Visualiser, plus platform extensions such as Analyze, Extension Manager, Skills and Summon. In the CLI, enable one with goose configure > Add Extension > Built-In Extension, or start a session with goose session --with-builtin developer.

goose's docs add that you are "free to" use these built-in MCP servers with other agents too. Check what is already on before adding outside servers, so you do not install a second tool that does the same job.

Install links

Server publishers can offer goose deeplinks:

goose://extension?cmd=npx&arg=-y&arg=%40modelcontextprotocol/server-github&timeout=<timeout>&id=<id>&name=<name>&description=<description>

For stdio links, goose's docs say cmd must be one of jbang, npx, uvx, goosed or docker. Remote links use url= and type=streamable_http. Every parameter must be URL-encoded.

Check it worked

Start a session and ask for something only the new extension can do. In Desktop, the button at the bottom of the app shows which extensions are on in the current chat. goose also suggests and enables extensions it thinks a task needs, but those stay on only for that session.

If an extension fails to activate in a locked-down corporate network, goose's docs point to their airgapped and offline setup page.

Common mistakes

• Leaving goose fully autonomous. Set permissions first.
• Writing command and env in YAML. goose uses cmd and envs.
• Putting secrets in config.yaml. Use goose's secret store via goose configure.
• Removing an enabled extension. goose's docs say you must disable it first.

Next step

Read Block and MCP for goose's background, and who owns MCP for how the AAIF works. To choose servers, try the MCP server finder.

Frequently asked questions