{
  "type": "ZkVmReceipt",
  "system": "risc0",
  "receiptFormat": "groth16-bn254",
  "imageId": "sha256:a1a0bc89b5b1febaeda3519f6dbade0fa5ac16beeb143c4e1b01689573567bc6",
  "seal": "GT0ieOk3H8vvmM7ygNO7qkNsHMJ5lnQxQqiYtn0puNwl99/R/Pikb96Ea4cMu0RLyXxPSvFsbBcQRW+3NUWcAhq/zxaPKlxSrxnRUSAf1wV+vbObNyeuZG/TOMZxYKbKD/bRJQOzhOMA9APMWaGcFSobufsxEIKEMDByJOx9YHISlxBC0i/kNOUgiD0RkfAjWiGmJD14TK1I68+htJZGgA0l0mubii1AbUUXItB3LBZp4sy+0SfQM3Q/Vq543eHJHKbdv4XGIzi6oNtw264j34O0fRWQSxTRN/2MAsOWcscs7o5gn2QleupbUAxlRBl66pcvderiPKvnSyjB77BtDg==",
  "journal": {
    "chaingraph_version": "0.4.0",
    "kernel_digest": "sha256:d3389851ebca78ebd45327e99035932bc36aa53855774154bd5abcd72afe7ae8",
    "output": {
      "crosswalk": [
        {
          "concept": "Authorization artifact",
          "values": {
            "acp": "Shared Payment Token",
            "ap2": "Payment Mandate (VDC)"
          }
        },
        {
          "concept": "Proof of user intent",
          "values": {
            "acp": "OAuth delegation + SPT",
            "ap2": "Signed mandate chain"
          }
        },
        {
          "concept": "Scope unit",
          "values": {
            "acp": "Merchant + cart total",
            "ap2": "Cart + amount"
          }
        },
        {
          "concept": "Settlement medium",
          "values": {
            "acp": "Card via PSP",
            "ap2": "Card or stablecoin"
          }
        },
        {
          "concept": "Identity / trust root",
          "values": {
            "acp": "OAuth 2.0",
            "ap2": "FIDO / VDC"
          }
        }
      ],
      "note": "Orientation snapshot only — verify every field against the cited primary source. Specs version monthly.",
      "protocol_names": [
        "AP2",
        "ACP"
      ],
      "protocols_compared": [
        "ap2",
        "acp"
      ],
      "protocols_detail": [
        {
          "artifact": "Checkout Mandate + Payment Mandate, expressed as Verifiable Digital Credentials (VDCs)",
          "audit": "Strong — non-repudiable chained VDC audit trail",
          "backer": "Google → donated to FIDO Alliance (2026)",
          "id": "ap2",
          "identity": "FIDO / verifiable credentials; rides on A2A",
          "name": "AP2",
          "rail": "Rail-agnostic — cards today; x402/stablecoin via the A2A x402 extension",
          "scope": "Cart + amount + payment instrument, bound at the Closed stage",
          "signed": "Cryptographically signed VDCs; Open→Closed mandate chain",
          "status": "v0.2; donated to FIDO Alliance (~Apr 2026)",
          "sub": "Agent Payments Protocol"
        },
        {
          "artifact": "Shared Payment Token (SPT) + Agentic Checkout session objects",
          "audit": "Order/session objects; PSP transaction record",
          "backer": "OpenAI + Stripe",
          "id": "acp",
          "identity": "OAuth 2.0 delegated auth",
          "name": "ACP",
          "rail": "Card via any compatible PSP (Stripe first); merchant stays merchant of record",
          "scope": "Single-use SPT scoped to merchant + cart total",
          "signed": "Delegated authorization (OAuth 2.0); PSP-issued SPT",
          "status": "beta; spec dated 2026-04-17",
          "sub": "Agentic Commerce Protocol (Shared Payment Token)"
        }
      ],
      "recommendation": {
        "also_consider": [
          "acp"
        ],
        "also_names": [
          "ACP"
        ],
        "primary_names": [
          "AP2"
        ],
        "primary_pick": [
          "ap2"
        ],
        "rationale": "A rail-agnostic, non-repudiable mandate chain across merchants is AP2's core design (Checkout + Payment Mandate VDCs). ACP fits if you are standardising on the OpenAI/Stripe checkout surface."
      },
      "scenario": "cross_merchant"
    }
  }
}