MCP Tools

Next.js DevTools MCP

next-devtools-mcp (current version 0.4.0) is Vercel's official MCP server for Next.js development. It is a thin connector: it discovers running Next.js 16+ dev servers and proxies their built-in MCP endpoint at /_next/mcp, plus provides two gateways — one to version-matched documentation, one to browser automation. As of 0.4.0 the server exposes exactly four tools: nextjs_index, nextjs_call, nextjs_docs, and browser_eval.

Setup

Add to project .mcp.json:

{
  "mcpServers": {
    "next-devtools": {
      "command": "npx",
      "args": ["-y", "next-devtools-mcp@latest"]
    }
  }
}

Or install via CLI:

# Universal (writes the right config for your detected client)
npx add-mcp next-devtools-mcp@latest

# Claude Code
claude mcp add next-devtools npx next-devtools-mcp@latest

# Cursor
# Go to Settings → MCP → New MCP Server

# VS Code
code --add-mcp '{"name":"next-devtools","command":"npx","args":["-y","next-devtools-mcp@latest"]}'

Requirements:

• Node.js v20.19+
• For runtime tools (nextjs_index, nextjs_call): Next.js 16+ with dev server running

Removed in 0.4.0: the init, upgrade_nextjs_16, and enable_cache_components tools no longer exist. Upgrade and Cache Components workflows now live in the upgrade codemod (npx @next/codemod@canary upgrade latest, or the next upgrade command in 16.1+) and the migration guide at /docs/app/guides/migrating-to-cache-components.

Tools Reference

nextjs_index

Discover all running Next.js 16+ dev servers and list their available MCP tools.

No parameters required. Returns JSON with discovered servers (port, PID, URL) and available tools.

Typical runtime tools per server (the exact set varies by Next.js version):

• get_errors — Current build, runtime, and type errors
• get_logs — Path to development log file
• get_page_metadata — Route and component metadata
• get_project_metadata — Project structure and config
• get_routes — All filesystem routes grouped by router type (added in 16.1)
• get_server_action_by_id — Look up Server Actions by ID
• get_compilation_issues — Compilation issues from the bundler (16.3+, Turbopack only)
• compile_route — Compile a route on demand; accepts a route specifier like /blog/[slug] or a path like /blog/hello (16.3+, Turbopack only)

nextjs_call

Execute a specific tool on a running Next.js dev server.

nextjs_docs

A gateway to version-accurate Next.js documentation. It no longer takes search/get parameters — instead it points the agent at the docs bundled with the installed Next.js version at node_modules/next/dist/docs/, which the agent then reads directly as files.

Since Next.js 16.3, next dev also auto-writes a version-matched AGENTS.md block pointing at these bundled docs (see /docs/app/guides/ai-agents), so agents get correct documentation with zero setup.

browser_eval

A gateway to the agent-browser CLI. It is not a Playwright action proxy — instead of taking start/navigate/click actions, it tells the agent how to install and run the agent-browser CLI for browser automation.

Use for:

• Verifying pages after changes
• Detecting hydration errors visually
• Taking screenshots for comparison
• Capturing browser console errors

Typical Workflow

1. Start dev server — npm run dev
2. Discover servers — Call nextjs_index to find running instances
3. Check errors — Call nextjs_call with get_errors
4. Read docs — Use the nextjs_docs gateway to locate the bundled docs, then read the files directly
5. Verify changes — Use the browser_eval gateway to drive agent-browser for screenshots and testing

Architecture

Coding Agent
      ↓
  next-devtools-mcp
      ↓
      ├─→ Next.js Dev Server (/_next/mcp) — Runtime diagnostics
      ├─→ agent-browser CLI (gateway) — Browser automation
      └─→ node_modules/next/dist/docs/ (gateway) — Version-matched docs

The MCP server bridges the agent to three systems: the running Next.js app, the agent-browser CLI, and the documentation bundled with the installed Next.js version.

Zero-Setup Docs Tip

Since Next.js 16.3, running next dev automatically maintains an AGENTS.md block in your project that points coding agents at the version-matched docs in node_modules/next/dist/docs/. No manual CLAUDE.md instructions are needed — the framework keeps agents aligned with the exact installed version.