UCP Checker
Check a store

What does a UCP agent find at your store?

We read the UCP profile at /.well-known/ucp, check it against the release it declares, call the services it lists, and show what we found and what to fix.

What you get back

two pages for your store
/status/yourstore.com
Verified yourstore.com HTTP statusUCP releaseMCP, REST, A2A, Embeddedcapabilitieswhen we checked

The status page. The verdict on your store, every finding with the spec rule it comes from, how your store answered each way in, and your UCP profile exactly as served.

/score/yourstore.com
0–100UCP Score · grade A to F points missing by areafixes that raise itspec breaksevery check

The score page. Your UCP Score and how it is made, the fixes that raise it with copy-ready code, and the spec rules it doesn’t count yet. Only a store whose UCP profile we could read gets a score.

Check trace

What we check at your store

There are five ways a UCP agent can reach a store. We try each one, record every request we make, and show what each one met. Shown here on an example store that offers all five; your result shows what your store met.

4 of 5 open
6 requests · 460 ms at the store · signed requests
  1. 01Hosting ↗
    Finding the profile
    Open
  2. 02Identity Linking ↗
    Acting for the buyer
    Offered
  3. 03Embedded ↗
    In the buyer's browser
    Declared
  4. 04Services ↗
    Calling its services
    Open
  5. 05continue_url ↗
    Sending the buyer to the website
    Offered
UCP CheckerUCPCheckerBot/1.0
  • Signed · Web Bot Auth
  • key example-ke…
How to verify us ↗
  • Finding the profile/.well-known/ucp · 200
  • read from profileActing for the buyerdeclared · accounts.yourstore.com
  • not calledIn the buyer's browserEmbedded · declared
  • Calling its servicesREST, MCP · answered
  • read from profileSending to the websitedeclared · /buy
  • Outside UCPhomepage · /llms.txt
  • Checked its linksspec · schemas · handlers
Open
01 · Finding the profile2 requests
Served at /.well-known/ucp with 200 OK, 4.4 KB. robots.txt allows /.well-known/ucp.
Offered
02 · Acting for the buyerread from profile
The buyer can sign the agent in to their own account through accounts.yourstore.com.
Declared
03 · In the buyer's browsernot called
Declared. We don't call it, so whether it works shows only in an agent run.
Open
04 · Calling its services2 requests
The REST service answered at its address. The MCP service answered tools/list in 140 ms.
Offered
05 · Sending the buyer to the websiteread from profile
An agent can hand over a ready cart at yourstore.com/buy.
01 · Finding the profile2 requests · 2 × 200 OK190 ms
GET /robots.txt 200 OK 1.1 KB · text/plain 60 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 10 ms
  • Download 5 ms
URL
https://yourstore.com/robots.txt
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
text/plain
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
text/plain
Got cache-control
public, max-age=300
GET /.well-known/ucp 200 OK 3.0 KB · application/json 120 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 70 ms
  • Download 5 ms
URL
https://yourstore.com/.well-known/ucp
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
application/json
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
application/json
Got cache-control
public, max-age=300
04 · Calling its services2 requests · 2 × 200 OK140 ms
POST /mcp 200 OK 8.0 KB · application/json 140 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 90 ms
  • Download 5 ms
URL
https://yourstore.com/mcp
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
application/json
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
application/json
Got cache-control
public, max-age=300
GET /ucp 200 OK 1.4 KB · application/json 90 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 40 ms
  • Download 5 ms
URL
https://yourstore.com/ucp
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
application/json
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
application/json
Got cache-control
public, max-age=300
Outside UCP · its other files2 requests · 2 × 200 OK110 ms
GET / 200 OK 46.9 KB · text/html 110 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 60 ms
  • Download 5 ms
URL
https://yourstore.com/
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
text/html
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
text/html
Got cache-control
public, max-age=300
GET /llms.txt 200 OK 2.2 KB · text/plain 60 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 10 ms
  • Download 5 ms
URL
https://yourstore.com/llms.txt
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
text/plain
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
text/plain
Got cache-control
public, max-age=300
Links in the profile · spec, schemas, handlers3 requests · 3 × 200 OK140 ms
GET ucp.dev/2026-08-25/schemas/shopping/checkout.json 200 OK 8.8 KB · application/json 130 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 80 ms
  • Download 5 ms
URL
https://ucp.dev/2026-08-25/schemas/shopping/checkout.json
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
application/json
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
application/json
Got cache-control
public, max-age=300
GET ucp.dev/2026-08-25/schemas/shopping/catalog_search.json 200 OK 5.9 KB · application/json 120 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 70 ms
  • Download 5 ms
URL
https://ucp.dev/2026-08-25/schemas/shopping/catalog_search.json
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
application/json
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
application/json
Got cache-control
public, max-age=300
GET ucp.dev/2026-08-25/specification/overview/ 200 OK 87.9 KB · text/html 140 ms

Answered.

  • DNS 8 ms
  • Connect 14 ms
  • TLS 22 ms
  • Wait 90 ms
  • Download 5 ms
URL
https://ucp.dev/2026-08-25/specification/overview/
Server
203.0.113.10
Sent user-agent
UCPCheckerBot/1.0 (+https://ucpchecker.com/methodology)
Sent accept
text/html
Sent signature-agent
"https://ucpchecker.com"
Sent signature
Web Bot Auth (RFC 9421)
Got content-type
text/html
Got cache-control
public, max-age=300
  1. 01 PROFILEValid against the 2026-08-25 schema; keys published
  2. 03 NOTEEmbedded service declared; not called by this check–

What the result says

Verified
The store publishes a UCP profile that is valid against the release it names. It doesn’t mean every agent purchase works: that shows only when an agent tries.
Invalid
We found a profile, but it breaks the release’s rules, for example a missing field or broken JSON. The result lists what to fix.
Not Detected
Nothing at /.well-known/ucp, usually HTTP 404. The result shows how a UCP profile starts.
Blocked
Our request was refused (HTTP 401 or 403), or robots.txt disallows it. That is what our checker met, not how the store treats other agents.
Unreachable
No answer: a timeout, a DNS or certificate error, or a server error (5xx).
Pending
In our list but not checked yet. Check it here to run it now.

Questions

Is the UCP Checker free?
Yes, with no sign-up. Checks are rate-limited so they stay fast for everyone.
Is the result live?
Pressing Check store runs a new check. A status page you open later shows when the store was last checked.
Does Verified mean UCP agents can buy here?
Not on its own. Verified means the profile is valid against its release and the services we called answered. Whether an agent can find a product and reach checkout shows only when an agent tries: UCP Playground sends one.
How is this different from the Validator?
The Checker reads a live store. The UCP Validator checks profile JSON you paste in, so you can test a profile before you publish it.
What is the UCP Score?
A number from 0 to 100 for a store whose profile we read, with the fixes that raise it. Each store’s score page shows how it is made; the methodology has the weights.