About UCP Checker
An independent checker for the Universal Commerce Protocol. We read what stores publish for UCP agents, check it against the spec, and show the result to anyone, free.
UCP Checker is the independent validation and observability layer for the Universal Commerce Protocol. We crawl, validate and grade every public UCP manifest we can find, run the merchant directory, the UCP Score, live adoption stats, the vertical guides and the authority-bound vendor map, and track the spec as it evolves so you don't have to — measured from two vantages (what a business declares, and what actually happens when an agent transacts), the same way for everyone, without picking winners.
Why independence matters
A readiness check is only useful if it has no stake in the answer. Platforms can't neutrally grade their own adoption, and tools tied to a checkout can't neutrally rank the alternatives.
We don't sell a commerce platform, a checkout or an agent, so there's nothing in a result we'd gain from moving up or down.
Every store is checked against the same public spec, the same way. No store can pay for a better result.
What each check looks at is documented, so anyone can see how a result was reached. An early snapshot of the directory (April 2026) is on Hugging Face under CC BY 4.0, no longer updated.
The check, the status pages, the score, the directory and both validators are free, with no account.
What we do
Check the profile
We read each store's /.well-known/ucp and check it against the release it declares: services, capabilities, payment handlers and keys.
How we checkRead what agents can reach
Every check reads robots.txt for our crawler and the main AI crawlers, and calls the services a profile declares.
UCPCheckerBotKeep a public directory
Every store we check, searchable by store platform, country and what it sells, each with its own status page.
The directoryWatch agents shop, separately
In UCP Playground, a separate product, AI models shop stores and every tool call is recorded. UCPCheckerBot itself never carts or checks out.
UCP Playground