Hoysal-25/Network_utility_MCP_Server

Network Utility MCP Server

A minimal, high-quality Model Context Protocol (MCP) server over STDIO that provides classic network utilities to an LLM/agent or a CLI client:

• 🔌 Port Check (telnet-style) – verify if a host:port is open or closed
• 🌐 DNS Lookup (nslookup-style) – A, AAAA, CNAME, MX, TXT, NS, SOA, ANY

Built with Node.js + TypeScript, with zero runtime dependencies. Implements JSON-RPC 2.0 over stdio to be MCP-friendly. Includes a small demo CLI client.

🚀 Quick Start

bash

1) Install dependencies

npm install

2) Build TypeScript

npm run build

3) Start MCP server (listens on stdio)

npm start

• Server logs → stderr
• JSON-RPC communication → stdin/stdout

🧪 Demo (No Agent Required)

Run the server and test it with the built-in demo client: bash

Terminal 1: Start server

npm run dev

Terminal 2: Run demo client

npm run demo Or send a single request using the included examples: bash

Example: Check port

node dist/mcpServer.js < examples/requests/portCheck.json

Example: DNS A record

node dist/mcpServer.js < examples/requests/dnsA.json

📡 JSON-RPC Methods

net.checkPort

Check if a TCP port is open on a given host.

Params:

json { "host": "example.com", "port": 80, "timeoutMs": 2000 }

Response:

json { "jsonrpc": "2.0", "id": 1, "result": { "open": true } }

dns.lookup

Resolve DNS records for a host.

Params:

{ "host": "example.com", "type": "A" }


**Response:**

json
{ "jsonrpc": "2.0", "id": 2, "result": ["93.184.216.34"] }

Supported record types: `A`, `AAAA`, `CNAME`, `MX`, `TXT`, `NS`, `SOA`, `ANY`

 📂 Project Structure

src/
  mcpServer.ts         # JSON-RPC over stdio server
  utils/
    portCheck.ts       # host:port checker
    dnsLookup.ts       # DNS resolver
  cli/
    demoClient.ts      # interactive CLI to test the server
examples/
  requests/            # sample JSON-RPC requests

🤝 Contributing

1. Fork the repo
2. Create a feature branch (`git checkout -b feature/my-feature`)
3. Commit changes (`git commit -m 'Add new feature'`)
4. Push to your branch (`git push origin feature/my-feature`)
5. Open a Pull Request 🎉