See what an agent finds, on every store you visit
The extension asks each store you browse for its UCP profile. The badge on the toolbar says whether there is one; a click shows its status, its endpoints, whether its release is the latest, its capabilities and payment handlers, and what changed since your last visit.
UCP CheckerThe badge tells you before you click
The store publishes a UCP profile. Click for what it declares, its endpoints, its status page, or a fresh check.
A profile is there, but an agent may not be able to use it: not valid JSON, a missing version, services or payment handlers, a service with no endpoint, an endpoint that isn't https, or a profile served through a redirect.
No UCP profile at /.well-known/ucp. Most stores, for now.
Something answered, but not a profile the extension could read: a block, an error page or broken JSON.
Who uses it
Check a client's store during an audit without opening developer tools: capabilities, payments and transports at a glance.
Confirm a store's MCP endpoint and release before you point an agent at it, then open it in UCP Playground.
Spot which brands are ready for agents as you browse, and share their public status page.
What it can see
It asks for as little as it can, and every request it makes goes without your cookies.
Host accessonly https://*/.well-known/ucpactiveTabthe current tab's domain, nothing else on the pagewebNavigationto notice you've moved to a new pagestorageits results and your settings, on your device
- The page you're on, or anything you type
- Your cookies or sign-in sessions
- Your browsing history
- Private or incognito windows
When the extension finds a UCP profile, it sends us the store's domain, the profile's address and the profile itself, with the time. Nothing about you or the page goes with it. Turn it off with the “Share what it finds” switch at the bottom of the popup.
