localhost-mcp

MCP server that inspects, manages, and kills local dev servers. Stop guessing what's on :3000.

Why

• Error: listen EADDRINUSE :::3000 — what's holding the port?
• 5 forgotten node / vite / next PIDs eating RAM from last week
• Switching projects → no idea which dev servers are still running
• lsof -i :3000, kill -9 <pid>, repeat

localhost-mcp makes it one tool call.

Install

npm install -g localhost-mcp
claude mcp add --scope user localhost -- localhost-mcp

Or zero-install via npx:

{
  "mcpServers": {
    "localhost": {
      "command": "npx",
      "args": ["-y", "localhost-mcp"]
    }
  }
}

Tools

Safety

• kill_server defaults to dry-run. Must pass confirm=true.
• Refuses PIDs < 1000 (system processes).
• Whitelisted dev processes only (node, python, ruby, go, deno, bun, php, java, rails, vite, next, etc).
• SIGTERM first, escalates to SIGKILL after 5s.

Frameworks detected

next.js, vite, nuxt, remix, astro, webpack-dev-server, esbuild, create-react-app, express, fastify, koa, hono, rails, django, flask, fastapi, uvicorn, gunicorn, deno, bun, php-builtin, jekyll, hugo. Falls back to package.json sniffing.

Platform support

• macOS — full
• Linux — full
• Windows — basic port scan only

Pairs with

terminal-history-mcp — what you ran + what's running = full dev environment memory for AI agents.

Source

• GitHub: https://github.com/HasanJahidul/localhost-mcp
• npm: https://www.npmjs.com/package/localhost-mcp
• License: MIT