ucp-checkout-rest

UCP checkout session state transitions work by managing a defined lifecycle from creation to completion or cancellation. The process enforces required REST headers like UCP-Agent, Idempotency-Key, and Request-Signature to ensure proper negotiation and secure transaction finalization for both merchant and platform clients.

UCP checkout REST implementation requires handling state transitions, mandatory headers like Idempotency-Key and Request-Signature, and error parsing for merchant and platform perspectives. It fetches live specification details to accurately map endpoint data types and manage the complete session lifecycle.

UCP checkout cancellation and completion are handled via REST operations that transition the session to its final state. The implementation manages required headers, parses error messages by severity, and fetches live specification endpoint details to ensure accurate transaction finalization for both merchant and platform clients.

You need live specification fetching for UCP REST endpoint details to dynamically retrieve accurate endpoint paths and data types. This ensures your checkout session management operations remain synchronized with the latest Universal Commerce Protocol requirements for transactions and state transitions.