UCP Checker
Check a store
UCP Score

UCP Score for artesanatoemcobre.com.br

Nearly there

84 out of 100, grade B: nearly there. The missing 16 points are spread across Conformance and Capabilities. 3 spec breaks on the status page aren't counted in the score.

Discovery 100Conformance 91Capabilities 58release 2026-04-08

UCP Score 84/100 grade B · nearly there
Points missing 16 Conformance, Capabilities Fixes 2 raise the score Spec breaks 3 not in the score

How the score is made

three areas, weighted
Discovery 30%
Can a UCP agent find and read the profile: HTTPS, an answer at /.well-known/ucp, robots.txt allowing it, and five files outside UCP (llms.txt, sitemap, Open Graph, Organization schema, viewport).
100full marks
Conformance 40%
Does the profile follow the spec: valid against its release (counted three times), a dated release, keys published, few warnings, spec and schema links that resolve.
91−3.6 pts
Capabilities 30%
What an agent can do here: how many capabilities, checkout, at least one service, payment handlers, and services that answer our check.
58−12.6 pts
A85–100Ready for UCP agents
B70–84Nearly there
C50–69Partly ready
D30–49Hard for UCP agents
F0–29Not ready

Raise the score

fixes that move the number
part of +4
1Publish the public keys agents use to check your messages
Your UCP profile lists no public keys, so an agent cannot confirm that a message really came from your store.
Agents use these keys to check that checkout messages really came from you. A store that takes payment through the agent needs them. A store that sends the buyer to its own checkout page can manage without them for now.
Conformance · effort medium 
{
  "keys": [
    {
      "kty": "EC",
      "crv": "P-256",
      "x": "<base64url x>",
      "y": "<base64url y>",
      "kid": "store-2026-10",
      "use": "sig",
      "alg": "ES256"
    }
  ],
  "ucp": { ... }
}

Create a P-256 (ES256) key pair: ES256 is the one algorithm every UCP agent must be able to check. Add the public key to a "keys" list at the top level of your UCP profile, as in the example, with its own "kid", and keep the private key on your server. The spec recommends a new key every 90 days: publish the new one next to the old, sign with it, and remove the old key a week later.

part of +4
2Move to the latest UCP protocol version
Your profile declares a valid but older protocol version. A newer one is published.
Older versions stay valid (agents use the version you declare), but newer abilities (embedded checkout, agent payment mandates, linked customer accounts, card authentication, payment terms and store location lookup) only work against the latest version. The profile itself barely changes: the signing keys move to a root-level "keys" list, and the rest of the update is in what capabilities can say.
Conformance · effort low 
"ucp": {
  "version": "2026-08-25",
  ...
},
"keys": [ ... ]   // beside "ucp", not inside it

Set the version to 2026-08-25 and publish your public keys as a root-level "keys" list. The older "signing_keys" field is still accepted, but "keys" is the one every verifier reads.

Every check

13 passed · 5 to fix
Agent Discovery · 8 of 8
8 OK
HTTPS, UCP profile reachable, AI bot access, llms.txt, sitemap.xml, Open Graph tags, Organization schema (JSON-LD), Mobile viewport metaShow
  • HTTPS · Profile URL uses https://
  • UCP profile reachable · HTTP 200
  • AI bot access · robots.txt allows /.well-known/ucp
  • llms.txt · Found at /llms.txt
  • sitemap.xml · Found at /sitemap.xml
  • Open Graph tags · og:title and og:type/url present
  • Organization schema (JSON-LD) · Organization-typed JSON-LD detected
  • Mobile viewport meta · <meta name="viewport"> present
UCP Conformance · 3 of 5
3 OK
Profile passes schema validation, Protocol version present and well-formed, Spec & schema URLs resolve (5)Show
  • Profile passes schema validation · No structural errors
  • Protocol version present and well-formed · Version: 2026-04-08
  • Spec & schema URLs resolve (5) · All 5 URLs resolved.
To fix
Public keys published
No keys list at the top level of the profile. Fix 1 above.
Conformance
To fix
No validation warnings
1 warning.
Conformance
Capability Coverage · 2 of 5
2 OK
Transports declared, MCP transport reachableShow
  • Transports declared · MCP
  • MCP transport reachable · tools/list returned a JSON-RPC response in 350ms
To fix
Capabilities declared
1 of 6 capability families detected: Catalog. A family counts once however many namespaces or extensions declare it.
Capabilities
Problem
Checkout capability
No checkout capability.
Capabilities
To fix
Payment handlers
Empty array: checkout-link redirect strategy.
Capabilities

Not in the score, but worth fixing first

spec breaks
Problem
The profile sits behind a redirect
artesanatoemcobre.com.br/.well-known/ucp answers 301 redirect. The spec forbids redirects on the profile, so an agent that asks artesanatoemcobre.com.br stops there. Serve it directly on every host agents use.
on the status page
Problem
The profile isn't served with the caching the spec requires
Served with Cache-Control "max-age=14400". Spec level: MUST. Not part of the UCP Score.
on the status page
To fix
The profile has no ETag or Last-Modified header
Spec level: SHOULD. Not part of the UCP Score.
on the status page

The score measures what the profile declares across the three areas above. These break a rule in the spec that agents follow, so they can stop an agent before the score matters.

Speed among Tray stores
The profile answered in 708 ms, faster than 73% of the Tray stores we check.