Are confirmation_uri and failure_uri attributes in the pay-outs section, mandatory?
No, they are not. But keep in mind that if you don't provide them, there's no way for us to notify you that the payout succeeded or failed. Therefore, it'll be up to you to call our GET /operations/<operationId> endpoint to know its status.
Is the "items" attribute mandatory for purchases?
Can I pass field amount different from the sum of amount * quantity from items?
No (if you do it anyway, it will be rejected by the server)
Can a customer deposit a different amount to the original invoice amount? If so, do you send the actual amount in a notification or in response to a transaction status query?
If yes, which field should be considered as the final processed amount indication?
No, they cannot deposit a different amount
Yes, we send the actual amount in the response
The attribute called “amount”
Is it possible for the customer to make several deposit attempts on your payment page? Will we receive multiple notifications?
Can users confirm a purchase using the Airtm mobile App?
No, they must confirm the purchase by logging into their Airtm accounts from the web browser.