Commerce protocols
Understand the implemented interfaces without assuming every rail is active.
MCP: the agent tool interface
MCP exposes discoverable tools with authenticated, scoped access. mandate0 serves Streamable HTTP on the platform's /api/mcp. Start with MCP setup.
UCP: storefront capabilities and checkout
The Universal Commerce Protocol describes discovery and a checkout lifecycle. WooCommerce publishes a profile at /.well-known/ucp; Shopify uses its configured App Proxy, by default /apps/aa. Storefront profiles describe supported services and payment handlers.
The live proxy implementation is TypeScript in packages/proxy, mounted in-process by the platform at /api/proxy. The Go source in apps/ucp-proxy is retired and is not the launch runtime.
AP2: authorization evidence
AP2-related mandate and cryptographic authorization code exists in the platform. These controls establish the authority under which an agent acts. The existence of a signed object alone is not evidence that a card was charged or a merchant order was created.
ACP: a separate API contract
The platform implements an ACP front door, including discovery and checkout-session routes. It has its own authentication header and payload contracts; do not apply a native REST example to it without reading the appropriate schema.
Launch boundaries
Stripe Connect destination-charge checkout is the intended launch payment path in the repository. Store connection, payment readiness, account readiness, scopes, authority and owner confirmation remain separate requirements.
A protocol implementation in source does not establish that a hosted feature is enabled, externally certified or listed in a third-party marketplace. The runtime's capability discovery and your account's readiness controls determine what you can use.