Mastercard VI

Mastercard VI uses SD-JWT credential chains to delegate payment authority from issuers to agents with explicit time and policy constraints.

Layered Credentials

Strong Signatures

Credential Chain Model

L1
L2 Immediate
L2 Autonomous
L3a/L3b

Algorithm Requirements

JWS: ES256
Curve: P-256
Hash: SHA-256

Constraint Types

Constraint	Intent
allowed_merchant	Permit transactions only for specific merchant identities.
line_items	Constrain purchasable SKUs/items and quantities.
allowed_payee	Restrict destination beneficiary/payee account.
amount	Set max/min transaction amount boundaries.
budget	Enforce cumulative spending ceiling over period.
recurrence	Define schedule rules for recurring charges.
agent_recurrence	Limit autonomous repeated actions by agent identity.
reference	Require transaction metadata/reference matching policy.

Credential Chain Validation Example

mastercard-vi-validate.ts

const result = await verifyViChain({
  algorithm: "ES256",
  credentials: {
    l1,
    l2,
    l3,
  },
  now: Date.now(),
});

if (!result.signaturesValid) throw new Error("Invalid signature chain");
if (!result.hashLinksValid) throw new Error("sd_hash mismatch");
if (!result.timeWindowsValid)
  throw new Error("Credential expired or not yet valid");

const policyDecision = evaluateConstraints({
  constraints: result.constraints,
  paymentRequest,
});

if (!policyDecision.allowed) {
  throw new Error("Constraint violation:" + policyDecision.reason);
}

Warning: Never skip L3 terminal validation even when L1/L2 are valid. L3 binds the delegated chain to the immediate transaction context.

Tip: Cache verified L1 trust anchors, but always recompute L2/L3 validity and constraint checks per authorization request.

Note: Feed normalized constraint results into your shared decision engine to keep Mastercard VI aligned with Visa TAP and AP2 policy outputs.

Google AP2 Voice WebSocket Protocol

​Mastercard VI

​Layered Credentials

​Strong Signatures

​Credential Chain Model

​Algorithm Requirements

​Constraint Types

​Credential Chain Validation Example

Mastercard VI

Layered Credentials

Strong Signatures

Credential Chain Model

Algorithm Requirements

Constraint Types

Credential Chain Validation Example