undici

What this client asked www.pathwren.workers.dev for, when, and what it got. Every number below is from this host's own server-side request log, 2026-09-01 00:36:09Z to 2026-09-03 06:01:15Z UTC.

undici

This name is an HTTP client library's default user-agent, not an operator identity: several unrelated programs can send it, and the rows below may be more than one party. 160 request(s) from 3 distinct address(es), 10 distinct path(s), first seen 2026-09-01 00:36:09Z, last seen 2026-09-03 06:01:15Z UTC. 30 separate visit(s), counting a gap of more than 30 minutes as a new one, median 66.4 minutes between them.

The user-agent strings, exactly as they arrived

user-agentrequestsaddressesfirst seenlast seen
undici16032026-09-01 00:36:09Z2026-09-03 06:01:15Z

What it asked for, in the order it asked

First request to each path, oldest first.

#pathat (UTC)status
1/mcp2026-09-01 00:36:09Z200
2/.well-known/oauth-protected-resource2026-09-01 01:07:30Z404
3/a2a2026-09-01 02:57:08Z200
4/c/mcp-registry-official/mcp2026-09-01 03:21:07Z200
5/c/mcp-registry-official/mcp/triage2026-09-01 10:07:56Z200
6/c/mcp-registry-official/mcp/doctor2026-09-01 10:07:57Z200
7/c/nanda/a2a2026-09-01 11:35:25Z200
8/c/mcp-registry-official/mcp/netcheck2026-09-02 01:34:55Z200
9/c/mcp-registry-official/mcp/robots2026-09-02 01:34:56Z200
10/c/mcp-registry-official/mcp/lint2026-09-02 18:44:48Z200

Everything it asked for

pathrequestsstatus codesfirstlast
/c/mcp-registry-official/mcp/netcheck41200×27, 202×9, 405×52026-09-02 01:34:55Z2026-09-03 06:00:00Z
/c/mcp-registry-official/mcp/triage29200×21, 202×5, 405×32026-09-01 10:07:56Z2026-09-03 05:59:39Z
/.well-known/oauth-protected-resource22404×222026-09-01 01:07:30Z2026-09-03 06:01:15Z
/c/mcp-registry-official/mcp17200×15, 202×1, 405×12026-09-01 03:21:07Z2026-09-03 05:59:37Z
/mcp17200×15, 202×1, 405×12026-09-01 00:36:09Z2026-09-03 05:59:36Z
/c/mcp-registry-official/mcp/doctor15200×152026-09-01 10:07:57Z2026-09-03 05:59:39Z
/c/mcp-registry-official/mcp/robots13200×11, 202×1, 405×12026-09-02 01:34:56Z2026-09-03 06:00:01Z
/c/mcp-registry-official/mcp/lint4200×42026-09-02 18:44:48Z2026-09-03 06:00:36Z
/a2a1200×12026-09-01 02:57:08Z2026-09-01 02:57:08Z
/c/nanda/a2a1200×12026-09-01 11:35:25Z2026-09-01 11:35:25Z

What it asked for that did not exist

path it asked forwhat it gotfirst askedsince then
/mcp405×12026-09-01 00:36:09Zstill absent
/.well-known/oauth-protected-resource404×222026-09-01 01:07:30Zstill absent — on purpose: No
/c/mcp-registry-official/mcp405×12026-09-01 03:21:07Zstill absent
/c/mcp-registry-official/mcp/triage405×32026-09-01 10:07:56Zstill absent
/c/mcp-registry-official/mcp/netcheck405×52026-09-02 01:34:55Zstill absent
/c/mcp-registry-official/mcp/robots405×12026-09-02 01:34:56Zstill absent

What it got, and what it sent

Status codes
200×110, 404×22, 202×17, 405×11
Accept headers
application/json, text/event-stream, */*, text/event-stream
Bytes served
689000
Attributed to a channel
mcp-registry-official (133), mcp-registry (3), nanda (1)
Our instrument classed it
agent×160 — that is our classifier's label from the user-agent, not the operator's, and it has been wrong before.

How to verify it is really them

Not observed. This client publishes no address list we could read and no reverse-DNS convention we could test, so the user-agent is the only identity it has here — and a user-agent is a claim, not a proof. Anyone can send this string.

What it publishes about you afterwards

Not observed. We have not seen this client publish a grade, a listing or a record about this host anywhere, and we make no claim that it does or does not.

Its own documentation

Not observed. It carries no URL and no contact address in its user-agent, so there is nowhere documented to ask what it is.

This page as data

curl -s https://www.pathwren.workers.dev/bot/undici.json
curl -s https://www.pathwren.workers.dev/data/observed-clients.json   # every client, one request

JSON · markdown · all clients seen here · index as JSON · check a crawler yourself, no key

Method, and what this page will not say

Rows come from a server-side log written before anything is served, so clients that run no JavaScript are counted exactly like browsers. The window is the whole life of the log, 2026-09-01 00:36:09Z to 2026-09-03 06:01:15Z UTC, and it is stated on every number because a count without a window is not a fact. Addresses are stored as salted hashes and counted, never printed. Our own checks send X-Self: 1 and are excluded, together with every request the analyst flagged as one of our own agents reaching for a URL through a model provider's fetch tool (the numbers are on the index). Nothing here is a claim about intent: where this page does not know something it says not observed.