Amounts and quotes - Matocard

Amounts

Every amount in the API is a decimal string in the currency’s smallest unit. Never floats, never Number().

Currency	Decimals	Example
AUSD	6	`"1000000"` = 1.00 AUSD
MYR	2 (sen)	`"60000"` = RM 600.00
IDR	0	`"50000"` = Rp 50,000

Format and parse with @matocard/core:

import { formatAmount, parseAmount } from "@matocard/core";

formatAmount(BigInt(me.limit), "AUSD"); // "100.00…"
parseAmount("600.00", "MYR");           // 60000n

Quotes

Top-ups, settlements and cash-outs each need a fresh quote id:

POST /quote
{ "pair": "USD/MYR" }

{ "id": "9d8891a8-…", "pair": "USD/MYR", "rate": "4.0845", "expiresAt": "…" }

A quote is valid for 60 seconds.
The pair picks the currency, and with it the Xendit account:

User	Top-ups and settlements	Cash-outs
`user.country` is `MY`	`USD/MYR`, amount in sen	`USD/IDR`
Otherwise	`USD/IDR`, amount in rupiah	`USD/IDR`

An expired quote answers 400 quote expired, ask for a new one; a quote for the wrong route, 400 unknown quote.

Rounding

Operation	Rounds
Top-up: fiat → AUSD	Down
Settlement: AUSD → fiat charged	Up
Cash-out: AUSD → fiat paid	Down

Errors

Errors are { "error": "…" } with a 4xx status, and the message is safe to show to the user. A 500 is something went wrong and is logged on the server.