next-devtools-mcp

What it does

The server bridges coding agents with Next.js development environments, providing runtime diagnostics and development guidance. For Next.js 16+, it connects to the embedded MCP endpoint on the dev server to expose live application state—including errors, route structures, and logs. The server also offers tools for exploring official Next.js documentation and assisting with framework upgrades and feature configuration across all Next.js versions.

Who it's for

Next.js developers using AI-assisted coding tools such as Claude, Cursor, Copilot, or Amp. Most useful for developers who want real-time visibility into their running applications, AI-powered help troubleshooting issues, and guidance navigating Next.js features and version upgrades.

Common use cases

• Query runtime errors and diagnostics from a live Next.js application
• Examine application route structure and configuration
• Review development server logs
• Get AI assistance upgrading Next.js to newer versions
• Enable framework features like Cache Components or Server Actions
• Search official Next.js documentation for API references and guides

Setup pitfalls

• Requires Node.js v20.19 or a newer LTS version; older versions are not supported
• Runtime diagnostics require Next.js 16+; earlier versions can use documentation and automation tools only
• Call the init tool before runtime queries to ensure proper context setup
• The development server must be running (npm run dev) and accessible at http://localhost:3000/_next/mcp (or your custom port)
• Modifies filesystem when assisting with upgrades or enabling features—review changes and keep version control clean