Unplugin

Add unplugin-mcp as a dev dependency to your project. For Rollup-specific usage you can also use the dedicated rollup-plugin-mcp package.

pnpm add -D unplugin-mcp
# or for Rollup specifically:
pnpm add -D rollup-plugin-mcp

Import the appropriate bundler-specific export from unplugin-mcp and add it to your plugins array. Choose which built-in tools to enable — ModuleTool and BundleSizeTool are Rollup-only while BuildConfigTool and BuildErrorTool work across bundlers.

// rollup.config.js
import { rollupPlugin as mcp } from 'unplugin-mcp';
import { ModuleTool, BuildConfigTool, BuildErrorTool, BundleSizeTool } from 'unplugin-mcp/tools';

export default defineConfig({
  plugins: [
    mcp({
      provideUnpluginMcpTools: () => [
        new ModuleTool(),
        new BuildConfigTool(),
        new BuildErrorTool(),
        new BundleSizeTool()
      ]
    })
  ]
});

Start the bundler in watch or dev mode. The MCP plugin will spin up an SSE server (default port 14514) that your MCP client can connect to while the build runs.

npx rollup -c --watch
# or for Vite:
npx vite

Add the SSE endpoint to your MCP client configuration. Because this server runs inside your build process it uses HTTP/SSE transport rather than stdio.

// ~/.config/cursor/mcp.json
{
  "mcpServers": {
    "rollup": {
      "url": "http://localhost:14514/mcp/sse"
    }
  }
}

With the build running and the client connected, ask your AI assistant to analyze module graphs, inspect configuration, or diagnose build errors using the exposed tools.