> ## Documentation Index
> Fetch the complete documentation index at: https://extension.js.org/llms.txt
> Use this file to discover all available pages before exploring further.

# extension.dev MCP server

> extension.dev ships an MCP server and an agent skill that work with Extension.js projects. Install pointer here, full documentation on docs.extension.dev.

[extension.dev](https://extension.dev), the platform that sponsors Extension.js, ships `@extension.dev/mcp`, a Model Context Protocol server, and `@extension.dev/skill`, an agent skill. Both are extension.dev products with their own repositories and documentation. They work with any Extension.js project. The server wraps the `extension` CLI and the local control channel that `extension dev` opens. An agent can then build, run, inspect and reload your extension in a real browser, with the same gates that the CLI enforces.

Extension.js itself is the framework and the CLI. Nothing in it depends on the agent tooling, and every operation that the server exposes is also a CLI verb. See [Debugging](/docs/debugging).

## Install

```bash theme={null}
claude mcp add extension-dev npx @extension.dev/mcp
```

Other clients and the plugin install are on [docs.extension.dev/tools/mcp](https://docs.extension.dev/tools/mcp).

## Where the documentation lives

* [MCP server](https://docs.extension.dev/tools/mcp): install, the tool list, session gates and login.
* [Agent skill](https://docs.extension.dev/tools/skill): what the skill teaches an agent and how to install it.
* [Run beside Chrome DevTools MCP](https://docs.extension.dev/tools/chrome-devtools-mcp): which server to reach for, and how to install both.

## Next steps

* [Chrome DevTools MCP](/docs/integrations/chrome-devtools-mcp): Google's Chrome debugging server as an integration.
* [Driving the CLI](/docs/workflows/driving-the-cli): the agent playbook for the CLI itself, no MCP required.
* [AI access via MCP and llms.txt](/docs/ai-access): give your assistant the docs.


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