AP2 — Agent Payments Protocol

Google's decentralised payment authorisation protocol — DID identity, SD-JWT mandate chain.

Google's decentralised payment authorisation protocol. Identity is via DID (Decentralised Identifier); authority is granted through mandates (intent / cart / payment) signed by a human supervisor. Agents declare the maximum transaction value they're authorised for, allowed currencies and regions, and whether human delegation is enabled.

The intent → cart → payment SD-JWT chain gets mandate verification + cross-merchant budget enforcement (deferred per §3.3.15).

You declare: agent DID, max transaction value, allowed currencies, allowed regions, mandate types, delegation flag.

PDLSS pre-fill: max transaction value flows to both autonomous and hard limits (the protocol-authorised amount IS the autonomous ceiling); allowed regions to jurisdictions; currency from the first allowed currency; delegation enables self-instantiation.

{
  "protocols": ["a2a", "ap2"],
  "ap2": {
    "agentDid": "did:web:agent.example.com",
    "policyClaims": {
      "maxTransactionValue": 500,
      "allowedCurrencies": ["USD"],
      "allowedRegions": ["US", "GB"]
    },
    "delegationEnabled": true,
    "mandateTypes": ["intent", "cart"]
  }
}