MCP API

The same domain-availability engine behind the site, exposed as an MCP server — so an AI agent can check domains inside its own workflow. Real registry data (DNS + RDAP). No account, no upsell.

Endpoint

Add this URL to Claude.ai, Cursor, or any MCP client:

https://mcp.icanhazdomain.com/mcp

Transport: streamable HTTP, stateless. No auth in v1 — the tools are public and read-only.

How to add it

Claude.ai / Claude Desktop: Settings → Connectors → Add custom connector → paste the URL above.
Cursor: Settings → MCP → Add server → use the URL as a streamable-HTTP server.
Any MCP client: point it at the endpoint as a streamable-HTTP MCP server.

Tools

check_domains

Many domain_labels × many domain_suffixes → availability for every combination in one call.

Pass a single label to check one name across many suffixes — ["openai"] × ["com","ai","dev"] — or many labels to compare a shortlist: ["uxrubric","uxeval","uxbench"] × ["com","ai","app"] → 9 results. Caps: 50 labels, 50 suffixes, ≤ 1000 combinations per call (split larger sweeps across calls).

Prefer plain HTTP?

The same engine answers a simple JSON API for non-MCP callers: POST https://mcp.icanhazdomain.com/api/check with { "domain_label": "openai", "domain_suffixes": ["com","ai"] }.