NS Lookup MCP Server

A simple MCP (Model Context Protocol) Server that exposes the nslookup command functionality. This service provides a REST API interface to perform DNS lookups, making it easy to integrate DNS resolution capabilities into your applications.

Features

Exposes nslookup command functionality via a REST API
Simple and focused microservice
Modern Python tooling with uv and pyproject.toml
Supports both forward and reverse DNS lookups
Configurable DNS server selection
Clean and concise output formatting

Requirements

Python 3.9 or higher
uv (Python package manager)

Installation

Clone the repository
Install dependencies using uv:

uv pip install -e .

Usage

Start the server:

uv run ns-lookup-mcp

Debug mode:

npx @modelcontextprotocol/inspector uv run ns-lookup-mcp

MCP Interface

Tools

The server exposes the following tool:

{
  "name": "nslookup",
  "description": "Performs DNS lookups using the nslookup command. Supports both forward and reverse DNS lookups.",
  "inputSchema": {
    "type": "object",
    "properties": {
      "hostname": {
        "type": "string",
        "description": "Domain name or IP address to look up"
      },
      "server": {
        "type": "string",
        "description": "Optional DNS server to use for the lookup"
      }
    },
    "required": ["hostname"]
  }
}

Prompts

The server provides the following prompt:

{
  "name": "nslookup",
  "description": "Perform a DNS lookup using nslookup",
  "arguments": [
    {
      "name": "hostname",
      "description": "Domain name or IP address to look up",
      "required": true
    },
    {
      "name": "server",
      "description": "Optional DNS server to use",
      "required": false
    }
  ]
}

MCP Client Configuration

To use this server with an MCP client, add the following configuration to your client's settings:

{
  "mcpServers": {
    "nslookup": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "[workspace]/ns-lookup-mcp",
        "ns-lookup-mcp"
      ]
    }
  }
}

Replace [workspace] with the actual path to your workspace directory.

Example Output

The server returns DNS lookup results in a clean, concise format:

DNS:    192.168.1.1
Name:   example.com
Address: 93.184.216.34

Common DNS Servers

Google DNS: 8.8.8.8
Cloudflare DNS: 1.1.1.1
OpenDNS: 208.67.222.222

License

MIT