Domain WHOIS MCP: availability checks, registration data, and domain suggestions

Domain WHOIS MCP lets AI agents inspect domain registration signals without parsing registry responses themselves. It combines registry RDAP lookups with a WHOIS.com fallback and exposes structured MCP tools for preliminary availability research, registration metadata, and keyword-based domain checks.

Use cases

• Check whether a candidate domain appears registered before naming a product or campaign.
• Retrieve registrar, creation date, expiry date, and name-server signals for research or operations.
• Inspect available raw WHOIS text when the fallback source supplies it.
• Test one keyword across several top-level domains for a naming shortlist.

MCP tools

Tool	Arguments	Result
check-domain	domain — required string, for example example.com	Human-readable text plus structuredContent containing domain, available, and optional registrar, creationDate, expiryDate, and nameServers.
whois-lookup	domain — required string	Human-readable WHOIS summary plus structuredContent with the same fields and optional rawWhois. Raw text is normally present only when the WHOIS.com fallback was used; an RDAP success produces structured fields without raw WHOIS text.
domain-suggestions	keyword — required string; tlds — optional string array, default ['.com', '.net', '.org', '.io', '.co']	Human-readable status lines plus structuredContent.suggestions, an array of { "domain", "tld", "available" }. The keyword is lowercased and characters outside letters, digits, and hyphens are removed. TLDs may be supplied with or without a leading dot.

The tools check only the exact domain or exact keyword + TLD combinations supplied. They do not invent alternate spellings or perform registrar purchases.

Connect from an MCP client

Use this exact Apify Streamable HTTP endpoint:

https://reverberant-equality--domain-whois-mcp.apify.actor/mcp

Authenticate every request through Apify with a Bearer token:

Authorization: Bearer <APIFY_API_TOKEN>
Content-Type: application/json
Accept: application/json, text/event-stream

Use POST /mcp with an MCP Streamable HTTP client and complete the standard initialization sequence. This is an MCP JSON-RPC endpoint, not a custom REST API. GET /mcp and DELETE /mcp return method-not-allowed responses.

Example tool call after initialization:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "domain-suggestions",
    "arguments": {
      "keyword": "northstar",
      "tlds": [".com", ".io", ".co"]
    }
  }
}

Read the display form from result.content[0].text or the machine-oriented form from result.structuredContent.

Pricing

The live price is $0.005 per tool call. Each tool emits one tool-call pay-per-event charge before performing its network work. domain-suggestions is one paid MCP call even though it checks several supplied TLDs sequentially. An inconclusive lookup or upstream error after charging can still consume the call. Apify platform usage is separate and follows the user’s Apify plan.

Data sources and lookup order

For .com and .net, the server first queries Verisign RDAP. For .org, it first queries the configured Afilias RDAP endpoint. Other TLDs skip the TLD-specific step. When a specific lookup does not yield a record, the server tries the rdap.org redirector and finally fetches https://www.whois.com/whois/{domain} for a best-effort HTML/WHOIS fallback.

RDAP JSON is normalized into registrar, registration/expiration dates, and name servers. Fallback WHOIS text is parsed with conservative regular expressions and may also be returned as rawWhois.

Limitations and error behavior

• Availability is an inference, not a purchase guarantee. A domain is reported available only when no RDAP record is found and fallback WHOIS text contains a recognized not-found phrase. If sources are blocked, time out, change format, or remain ambiguous, the code conservatively reports available: false.
• TLD-specific RDAP configuration exists only for .com, .net, and .org; other registries depend on rdap.org discovery and the fallback.
• WHOIS.com may rate-limit or block automated requests, and its HTML can change. Registry privacy/redaction can omit registrant data.
• Input is accepted as a string rather than fully validating domain syntax. Supply a bare domain such as example.com, without a protocol, path, or email address.
• check-domain and whois-lookup perform separate information and availability passes, so one tool call can make multiple upstream requests.
• A total retrieval failure returns sparse data and treats the domain as not confirmed available rather than throwing. Unexpected handler errors are logged and surfaced as MCP errors.
• Results are point-in-time signals. Confirm important decisions directly with an accredited registrar or the authoritative registry.

Privacy

No tool result is written to an Actor dataset, key-value store, or application database. Domains, keywords, and TLD selections are processed in memory and included in application logs. Requested domains are sent to one or more registry/RDAP services and potentially WHOIS.com, which receive normal network metadata under their own policies. Avoid sensitive internal naming candidates if disclosure to those services is unacceptable. Keep the Apify token in secret client configuration.

Local development

Requires Node.js 20 or newer:

npm install
npm run start:dev       # local MCP endpoint: http://localhost:3000/mcp
npm test                # run Vitest
npm run build           # compile TypeScript into dist/
npm run start:prod      # run the compiled server
apify validate-schema   # validate Actor configuration/schema

Set APIFY_CONTAINER_PORT to use a port other than 3000. Local runs may ignore PPE charging when no monetized Apify environment is active.