From a direct Belize Bank integration

If you already call register.do yourself, here is what each of those calls becomes — and what you get to stop doing.

The mapping

What you call today	What it becomes
`register.do`	`POST /v1/payment_intents` then `POST /v1/checkout_sessions`. Redirect to the session’s `url` instead of to `formUrl`.
`registerPreAuth.do`	The same, with `capture_method: "manual"`.
`deposit.do`	`POST /v1/payment_intents/:id/capture`
`reverse.do`	`POST /v1/payment_intents/:id/cancel` for an uncaptured hold; a full refund otherwise. You no longer choose between reverse and refund.
`refund.do`	`POST /v1/refunds`
`getOrderStatusExtended.do`	`GET /v1/payment_intents/:id` — though mostly you will not need it, because the webhook tells you.
`paymentOrderBinding.do`	`POST /v1/payment_intents` with `payment_method` and `off_session: true`.
`getBindings.do`	`GET /v1/customers/:id/payment_methods`
`dynamicCallbackUrl`	A webhook endpoint you register once, signed and retried.

Fields you already have

Theirs	Ours
`mdOrder`	`payment_intent.gateway.order_id`
`orderStatus`	the payment’s `status`, plus `gateway.order_status` if you want the raw number
`actionCode`	`last_payment_error.decline_code`, and the raw value in `gateway.action_code`
`approvalCode`	`gateway.approval_code`
`maskedPan`	`gateway.masked_pan`
`bindingId`	a `payment_method` on a customer
`orderNumber`	ours, and yours goes in `metadata`

Amounts work the same way

Minor units, as you are used to. The difference is that if you price in US dollars, you now send the US dollar amount and we record what the card was charged in Belize dollars alongside it, with the rate. You no longer convert before calling.

const intent = await sp.paymentIntents.create({
  amount: 6000,          // USD 60.00 — not converted by you
  currency: "usd",
  description: "SCU-B0161 — Blue Hole Two-Tank",
  metadata: { shop_id: "scuba-sensation", booking_id: "SCU-B0161" },
});

// after it is paid:
intent.settlement_amount;   // 12000 — BZD, what the card was charged
intent.fx_rate;             // 2

What you get to delete

The gateway credentials and the code that holds them. The callback endpoint, its hostname, and the forgery checks around it. The reconciliation sweep for payments the callback never arrived for. The retry logic around getOrderStatusExtended. The currency conversion. The logic that decides between a reversal and a refund.

All of that still happens — it is simply on our side of the line now, and it is the same set of problems whether one merchant solves them or all of them do.

Keep your own ledger. We record what the bank did and what we owe you; your books record what the payment was for. Those are different questions, and a payment platform should not be the only place your business records a sale.

Moving over without a flag day

Nothing requires a cutover. Run both: send new payments here while old ones finish where they are. A payment taken directly stays refundable directly, and one taken here is refundable here — there is no state to migrate, because a payment belongs to whoever took it.