Universal Commerce Protocol Adapter (UCP)

UCP — Universal Commerce Protocol Adapter

Contract-only documentation for Universal Commerce Protocol Adapter (UCP).

Status

• Implementation: implemented (Phase 1: checkout capability; Phase 2/3 stubs for order webhooks, identity linking)
• OpenAPI: /ucp/openapi.yaml

Scope

• Platform-aware checkout adapter following UCP spec v2026-01-11.
• Dual-auth: admin (session/api-key) and platform (client_id/secret) credentials.
• Exposes standardized commerce endpoints for external platforms (AI agents, apps, search engines).
• No UI; headless API + eventing only.

Clarifications

• Checkout sessions: full cart state with line items, buyer info, pricing, and escalation handling. FSM: incomplete → ready_for_complete → complete_in_progress → completed.
• Platform credentials: client_id + client_secret managed by admins via platform CRUD. Secrets hashed with SHA-256, timing-safe comparison.
• Order creation: checkout/complete delegates to SCM via internal-invoke with channel_code 'ucp'.
• Capability profiles: per-org UCP configuration via GET /.well-known/ucp?orgcode=X (no auth).