@thexjs/mcp

An MCP server that gives AI coding agents (Claude Code, Claude Desktop, Cursor, Windsurf, etc.) grounded, accurate knowledge of the x framework — instead of letting them pattern-match to Next.js / Remix / Astro / TanStack Start syntax that looks similar but isn't the same.

Every project scaffolded with bun create thexjs-app@latest already wires this up (.mcp.json for Claude Code, .cursor/mcp.json for Cursor). To add it to an existing project by hand:

{
  "mcpServers": {
    "thexjs": {
      "command": "bunx",
      "args": ["@thexjs/mcp"]
    }
  }
}

Tools

• list_topics — lists every doc topic (routing, loaders, actions, env, auth, config, ...).
• get_docs — returns grounded reference docs for a topic, including explicit "this is NOT X's syntax" corrections for the conventions agents most often get wrong (loaders, server actions, env prefixing).
• search_docs — full-text search across all topics.
• scaffold_file — generates a correctly-shaped file (page, dynamic page, layout, middleware, api-route, action) with the right exports, path, and conventions, ready to paste.

Why this exists

x deliberately diverges from Next.js/Remix/TanStack Start in a few specific places (no "use server" directives, underscore-prefixed special files, THEXJS_PUBLIC_ env prefix, loader args that are { params, request } rather than { context }). Those are exactly the details a general-purpose coding agent is likely to get wrong from training data alone, confidently. This server is the fix: ground the agent in the framework's actual conventions before it writes code, rather than relying on it to have memorized a small framework's syntax correctly.

Local dev / run without publishing

bun run start   # from packages/mcp — runs src/index.ts directly over stdio