WhoisJSON MCP Server — WHOIS & DNS tools for AI assistants
Give Claude, Cursor, or Windsurf direct access to WHOIS lookups, DNS records, SSL certificates, and domain availability — from your AI chat, without writing a single line of code.
What is the Model Context Protocol?
The Model Context Protocol (MCP) is an open standard that lets AI assistants call external tools — APIs, databases, services — in a safe, structured way. Instead of copying and pasting data into a chat window, the AI fetches it on your behalf, in real time.
How does it work with WhoisJSON?
Install the WhoisJSON MCP server once, add your API key to the config file, and from that point on any supported AI client can run WHOIS lookups, DNS queries, SSL checks, and availability tests — just by asking in plain English. No webhooks, no glue code, no context switching.
One key, two access modes
Your WhoisJSON API key works identically for the REST API and the MCP server. The MCP server is published as@whoisjson/mcp-server on npm and the source is available onGitHub. It runs locally vianpx — nothing to install permanently.
Four tools, ready to use
Each MCP tool maps directly to a WhoisJSON API endpoint. Ask your AI to use them by name or just describe what you need.
WHOIS Lookup
Full WHOIS record for any domain — registrar, registration and expiry dates, nameservers, and contact info.
DNS Lookup
All DNS records in one call — A, AAAA, MX, TXT, CNAME, NS, SOA, and PTR.
SSL Certificate
TLS certificate details — issuer, expiry date, SANs, and full chain validity.
Domain Availability
Instant availability check — registered or free, for any TLD.
Set up in under two minutes
Add the block below to your AI client's MCP config file, replaceYOUR_API_KEY, and restart.
Edit the config file for your OS, then restart Claude Desktop.
%APPDATA%\Claude\claude_desktop_config.json~/Library/Application Support/Claude/claude_desktop_config.json~/.config/Claude/claude_desktop_config.json{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "YOUR_API_KEY"
}
}
}
}
In Cursor, openSettings → MCP → Add new MCP server, choosecommand type, and paste the config below.
~/.cursor/mcp.json{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "YOUR_API_KEY"
}
}
}
}
In Windsurf, openCascade → MCP Servers → Configure and add the entry below.
~/.codeium/windsurf/mcp_config.json{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "YOUR_API_KEY"
}
}
}
}
Just ask — your AI does the rest
Once the server is connected, try these in Claude, Cursor, or Windsurf.
"Who owns github.com and when does it expire?"
"What are the MX and SPF records for stripe.com?"
"Check the SSL certificate for openai.com — is it still valid?"
"Is coolstartupname.io available to register?"
Start using WhoisJSON in your AI assistant today
Create your free account, grab your API key, and paste it into the config. That's it.