Universal Commerce Protocol profile absent
UCP_PROFILE_ABSENT · v1.0
What it detects
No Universal Commerce Protocol profile is published at /.well-known/ucp.
Why it matters
UCP is the emerging standard agents use to discover a merchant's checkout, capabilities, and signing keys in one machine-readable document; without a profile, an agent has no standardized way to transact with the site at all.
How to fix
- Check for a JSON profile at `/.well-known/ucp` (the Universal Commerce Protocol discovery path, spec at ucp.dev). - Publish a minimal UCP profile declaring `ucp_version`, `merchant` (name, url), a `checkout` service endpoint, and a `signing_keys` array (see `UCP_SIGNING_KEYS_INVALID` for key format). - Reference ucp.dev/specification/overview for the full schema and github.com/Universal-Commerce-Protocol/samples for working reference implementations to adapt. - Verify: `curl` `/.well-known/ucp`, confirm HTTP 200 with valid JSON, and run it through the official conformance suite (github.com/Universal-Commerce-Protocol/conformance).
References
Last reviewed: 2026-09-01 · rule v1.0