Summary
Connects Claude to the WhoisJSON API for domain intelligence lookups. You get four tools: whois_lookup pulls registration data like registrar info and nameservers, dns_lookup fetches all DNS records including A, MX, TXT, and DMARC, ssl_check validates certificates, and domain_availability tells you if a domain is up for grabs. Requires a WhoisJSON API key from their dashboard. Useful when you need to audit domain configurations, investigate ownership chains, or check SSL expiry dates without leaving your conversation. Runs via npx with stdio transport, so setup is just dropping your API key into Claude's config.
Keep your Mac awake while Claude Code and 40+ AI agents run. Sleeps when they're idle.
One time payment $9 →
Integrate web data into your AI product. One API to scrape website & brand data.
Get API Key Now →
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@whoisjson/mcp-server
MCP (Model Context Protocol) server for the WhoisJSON API. Exposes WHOIS, DNS, SSL, and domain availability lookups as tools for AI assistants.
Tools
| Tool | Description |
|---|---|
whois_lookup | WHOIS registration data for a domain (registrar, dates, contacts, nameservers…) |
dns_lookup | All DNS records for a domain (A, AAAA, MX, NS, TXT, CNAME, SOA, CAA, DMARC…) |
ssl_check | SSL/TLS certificate details and validity for a domain |
domain_availability | Check if a domain is available for registration |
Prerequisites
- Sign up at whoisjson.com and copy your API key from the dashboard.
- Node.js ≥ 18.
Installation
npm install -g @whoisjson/mcp-server
# or run directly with npx (no install needed):
npx @whoisjson/mcp-server
Configuration
Claude Desktop
Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or
%APPDATA%\Claude\claude_desktop_config.json (Windows):
{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "your_api_key_here"
}
}
}
}
Cursor
Edit ~/.cursor/mcp.json:
{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "your_api_key_here"
}
}
}
}
Windsurf
Edit ~/.codeium/windsurf/mcp_config.json:
{
"mcpServers": {
"whoisjson": {
"command": "npx",
"args": ["-y", "@whoisjson/mcp-server"],
"env": {
"WHOISJSON_API_KEY": "your_api_key_here"
}
}
}
}
Running locally (development)
cd mcp-server
npm install
npm run build
WHOISJSON_API_KEY=your_key npm start
Publishing
npm run build
npm publish --access public
API reference
Full API documentation: whoisjson.com/documentation
Featured
Keep your Mac awake while Claude Code and 40+ AI agents run. Sleeps when they're idle.
One time payment $9 →Integrate web data into your AI product. One API to scrape website & brand data.
Get API Key Now →Agent, run crypto. Access onchain data & trade routes via 1inch.
Install now →On Capafy, your Skill runs online 24/7 as an agent product, and you get paid every time someone uses it.
Start earning →Configuration
WHOISJSON_API_KEY*secretYour WhoisJSON API key from whoisjson.com/dashboard
Registryactive
Package@whoisjson/mcp-server
TransportSTDIO
AuthRequired
UpdatedApr 9, 2026