Probability score (agent)

Definition

Mastercard's score of the likelihood that a transaction was initiated by an AI agent, given to issuers for authorisation decisions.

Example

Rolling out for testing in the US from 30 Sep 2026. mastercard.com, read 4 Nov 2026.

Where it appears in the sourced facts

• Version 2026-04-17 added a Feed API where merchants push catalog data to agent-hosted endpoints (POST /feeds, PATCH /feeds/{id}/products), and deprecated 2026-01-30. github.com, read 4 Nov 2026. In Agentic Commerce Protocol (ACP).
• The README says ACP lets an AI agent embed commerce "without being the merchant of record". github.com, read 4 Nov 2026. In Agentic Commerce Protocol (ACP).
• Visa Intelligent Commerce Connect lists ACP among the four protocols it accepts for agent-initiated payments, in pilot from April 2026. visa.co.uk, read 4 Nov 2026. In Agentic Commerce Protocol (ACP).
• Businesses publish their UCP profile at /.well-known/ucp; platforms send their own profile URI per request in the UCP-Agent header. ucp.dev, read 4 Nov 2026. In Universal Commerce Protocol (UCP).
• The spec defines transports rest (OpenAPI 3.x), mcp (OpenRPC), a2a (Agent Card) and embedded (OpenRPC), and a payment_handlers registry that must be present even when empty. ucp.dev, read 4 Nov 2026. In Universal Commerce Protocol (UCP).

Nearby terms

• Agent Pay for Machines (AP4M)
• Know Your Agent (KYA)
• Dynamic Token Verification Code
• All terms