There are two fields to pass your order ID and the purpose to the transaction. The order ID helps you to connect with your system. The purpose is shown at the bank statements of the customer, but also in your advice notes for the payout.
The field names are:
transactionRef: purpose text for bank statement;merchantRef: order ID for secuOffice.
Example request body:
Smart Transaction
{ ... "transactionRef": "Bestellung am 25.02.21 bei Example.com", "merchantRef": "20000345", ...}Neither order ID nor purpose are visible in Smart Checkout.