{
  "payment_type": "hvac_invoice",
  "ledger_entry_type": "hvac_invoice_approve",
  "authorization": "Confirm the approved service report, parts, labor, and customer total before collecting payment.",
  "amounts": "Positive integer strings in USD cents, resolved server-side from approved records.",
  "identity": "Authenticate the payer and resolve the Ledger and business record server-side.",
  "idempotency": "Persist one stable key and exact payload per operation. Recover existing operations after timeouts.",
  "concurrency": "Serialize collection attempts per approved invoice and cap collection at its outstanding balance.",
  "settlement": "Verify Payment status on the server. Never post native settlement entries manually.",
  "domain_rules": {
    "Additional parts": "Obtain approval for parts outside the original quote before updating the collectible invoice.",
    "Warranty work": "Remove amounts covered by warranty before requesting the customer's card payment.",
    "Repeat service visit": "Use the service invoice identifier, not just the property address, to match each receipt."
  }
}