drwho.me developer tools

drwho.me

Free tools for domains, mail and the web, and a free MCP server that gives the same tools to AI agents. No account, no API key.

• Site: https://drwho.me
• MCP endpoint: https://drwho.me/mcp/mcp (streamable HTTP)

DNS and most email checks run in your browser (17 of the 32 tools), so the domain never reaches drwho.me. SPF, DMARC, DKIM, TLS-RPT and the blacklist check go from your browser straight to Cloudflare's public DNS. Site checks, WHOIS and the certificate log run on the server, which does not store what you check. So do MTA-STS and the other tools that must read another site's response or open a socket.

drwho.me is built by Hikmah Technologies, the team behind Domain Posture. Each tool here checks one thing. Domain Posture runs every check at once, grades them and tells you what to fix first.

Use the MCP server

Claude Code:

claude mcp add --transport http drwho https://drwho.me/mcp/mcp

Most other clients take this shape (check your client's docs):

{ "mcpServers": { "drwho": { "url": "https://drwho.me/mcp/mcp" } } }

Fair use: 60 tool calls per hour per address. Listing the tools is never limited. On the website, server-side checks are limited to 60 an hour per address (30 an hour shared by requests with no address), and IP lookup to 30 an hour.

To run it yourself over stdio:

docker build -t drwho-mcp .
docker run -i --rm drwho-mcp

Tools

Tool	What it does
dossier_summary	Nine DNS, email and TLS checks on a domain, one graded line each
dossier_dns, dossier_mx, dossier_dnssec	DNS records, mail servers, DNSSEC
dossier_spf, dossier_dmarc, dossier_dkim	Email authentication
dossier_mta_sts, dossier_tlsrpt	Inbound mail TLS policy and reporting
dossier_tls, dossier_headers, dossier_redirects, dossier_cors	TLS certificate, response headers, redirect chain, CORS preflight
dossier_web_surface, dossier_ai_crawlers, dossier_llms_txt, dossier_security_txt	robots.txt, sitemap, page metadata, AI-crawler policy, llms.txt, security.txt
dossier_whois, dossier_ct_log	Registration data, subdomains in certificate logs
dns_lookup, ip_lookup, user_agent_parse	One DNS record type, IP location and network, user agent parsing
base64_encode, base64_decode, jwt_decode, json_format, url_encode, url_decode, uuid_generate	Developer utilities, run locally

Every tool is read-only. A result for a domain also links to the full graded report on Domain Posture.

How it is built

TypeScript on Node 22. Hono renders the pages on the server as plain HTML. There is no client framework: two small custom elements (<dw-check>, <dw-live>) run the tools in the page. The check logic is the MIT-licensed @hikmahtech/dossier-checks package, shared by the browser, the server and the MCP server.

src/content/tools.ts   the tool list; pages, sitemap and navigation read it
src/checks/            which checks run in the browser and which on the server
src/reports/           turns a check result into a report: a verdict and rows
src/lib/               pure logic for the developer tools (also used by MCP)
src/client/            browser scripts, one bundle per tool kind
src/views/             pages; tool views are found by file name
src/mcp/               the MCP tools, the HTTP endpoint, the manifests
src/server/            client address, rate limit, outbound network guard

docs/ADDING_A_TOOL.md explains how to add a tool.

Safety

The server fetches sites that visitors name, so it guards its own network. Before a check runs, the domain must resolve only to public addresses. On top of that, every outgoing connection is checked at the socket layer, whichever library opens it, so a redirect, a changed DNS answer or a WHOIS referral cannot reach a private address. See src/server/ssrf.ts.

The content security policy allows no inline or evaluated script.

Run it

pnpm install
pnpm dev          # http://localhost:3000
pnpm test
pnpm lint

Configuration is in .env.example. Everything is optional: without IPINFO_TOKEN the two IP tools say they are not configured, and without GA_MEASUREMENT_ID no analytics loads. MCP tool calls are counted in a separate GA4 property set by GA_MCP_MEASUREMENT_ID and GA_MCP_API_SECRET; without both, none are sent. Each event carries the client's name and version and a caller id: a keyed hash of the caller's address whose key changes every UTC day, so GA can count distinct callers per day but never sees an address or the domain checked. Set MCP_CALLER_SALT to a long random value to keep ids stable across restarts within a day.

glama.json and server.json are generated from the code with pnpm manifests. A test fails if they are out of date.

Deploy

Dockerfile.web is the website and the hosted MCP endpoint. Dockerfile is the stdio MCP server. .paas/app.yaml is the manifest for koyracloud.

Unknown paths redirect to the same path on domainposture.com. drwho.me used to be that product's address, and links and signed documents issued then must keep working.

Licence

MIT