Protocol
HIGH/.well-known/ucp returns 200 directly with no redirects
Fetching `/.well-known/ucp` returns 200 with no redirect chain. Lightweight agent clients fetch `/.well-known/ucp` without following redirects — a 301/302 means they never see your profile.
What this check looks for
Per the UCP overview, the profile lives at the canonical well-known URI. We require the GET to return 200 directly. Any 3xx response (or a status indicating a followed redirect chain) breaks the contract for lightweight agent runtimes that fetch the profile without following hops. Transport metadata for this check is populated by the v2 runner (Task I1); until then the check returns `na`.
Which AI surfaces it affects
- Google AI Mode (UCP)100
- Microsoft Copilot70
- ChatGPT (ACP)30
- Meta AI30
- Perplexity20
Weighted against the live specs — ACP 2026-04-17, UCP 2026-04-08.
How to fix it
Serve /.well-known/ucp directly with a 200 response
Shopify
Developer- Shopify storefronts often 301 well-known requests through the apex. Add a Shopify Function or proxy that responds directly with the UCP JSON instead of redirecting.
BigCommerce
Developer- Use a Cloudflare Worker (or your CDN's edge function) to serve `/.well-known/ucp` directly on the apex host; avoid redirecting to a subdomain.
WooCommerce
Developer- Place the UCP JSON file at the document root under `/.well-known/ucp` (no .html extension) and configure your webserver to return it with a 200 — not a redirect to /ucp/ or similar.
Custom / headless
Developer- Bind the canonical URL `/.well-known/ucp` to your handler with a direct 200 response — no `Location:` header.
GET /.well-known/ucp HTTP/1.1
Host: example.com
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: public, max-age=3600
{ "version": "2026-04-08", ... }The spec it's pinned to
UCP overview — profile location is stable
The UCP overview names `/.well-known/ucp` as the canonical, stable profile location. Returning 3xx forces agents to handle redirect chains; lightweight runtimes drop the profile entirely.
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