Who is calling? — the one endpoint that needs nothing from you

Takes no arguments at all. It answers about the request you just made: the user-agent you sent, the address you came from, whether the crawler index recognises you, whether any operator publishes a prefix containing your address, the class this host's own instrument books you as, and whether we have seen you here before and what you fetched. Every fact comes from your own request headers or from a file this host already publishes; nothing is fetched and nothing about you is invented.

Copy this

curl -s 'https://www.pathwren.workers.dev/tools/whoami?s=client-dossiers'

Your own dossier: what this host can see about the client making the request, with no argument given.

curl -s 'https://www.pathwren.workers.dev/tools/whoami?spec=1&s=client-dossiers'

The specification of this endpoint instead of the answer: what it returns, which MCP tool answers it, and the caveats.

Run it in a browser — it answers JSON with access-control-allow-origin: *, so fetch() works from any page with no proxy.

No setup at all

• No account, no key, no token, no handshake, no session.
• GET (and HEAD). Anything else answers 405 with an Allow header and points at the MCP endpoint.
• Cacheable: max-age=0, a strong ETag, and a 304 when you send it back.
• Asked with nothing at all it answers for real — a bare GET /tools/whoami is the whole call. Add ?spec=1 if you wanted the specification instead.
• CC0-1.0. Nothing is logged about you beyond the request line this host publishes about every client, including itself.

Parameters

None. This endpoint takes no arguments at all — that is the point of it. Every other endpoint here needs something you have to supply; this one needs nothing, so it is the one you can call before you know anything about this host.

The same tool over MCP

This endpoint holds no copy of the logic: it calls whoami on the ai-crawler-index MCP server in-process, through that server's own JSON-RPC envelope. One implementation, two doors — an answer that changes here changed there.

curl -s https://www.pathwren.workers.dev/mcp \
  -H 'content-type: application/json' \
  -H 'accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call",
       "params":{"name":"whoami","arguments":{}}}'

What it will not do

• The answer depends on your request headers, so it is not cached and carries no ETag comparison across callers.
• Nothing is stored. The published file it reads, /data/observed-clients.json, is built from this host's own access log and is already public.
• The same answer over MCP: tools/call whoami with arguments {} on any of the five servers here.
• It fetches nothing. No argument here or on the MCP tool behind it takes a URL, and neither makes any outbound request: every answer comes out of files this host already publishes.

Also here

• The other 7 endpoints, one page each.
• 123 clients that actually crawled this host, 2026-08-31 20:58:11Z to 2026-09-02 04:57:09Z UTC, one page each.
• /data/observed-clients.json — that whole set in one request.