Each API has an associated schema file or XSDs (XML Schema Definitions). These are explained in detail in this document. Each API is associated with putting files (PUT) onto the server or getting files (GET) from the server.
When sending files to the Seller Portal, there is a multi-step process to confirm the file was accepted and processed without any errors. A “200 (OK)” response from the API call only means we accepted the file and does not mean that we processed the file without any issues.
PUT calls require a follow up call using the doc ID using the processing report. For returns and refunds, there is a separate call to ensure that the return/refund was processed in our order management system. The below flow diagram illustrates the system flow.
Example of the end-to-end PUT API flow for ASNs

Example of the end-to-end PUT API flow for Returns/Refunds
