{
  "amount": "50.00",
  "currency": "USDC",
  "description": "Order #12345 - 2x Widget Pro",
  "metadata": {
    "customer_id": "cust_42",
    "order_id": "ord_99"
  },
  "successRedirectUrl": "https://yourstore.com/success",
  "failRedirectUrl": "https://yourstore.com/cancel",
  "expiresAt": "2026-06-14T10:30:00Z"
}