Amazon Marketplace Web Service (MWS) will no longer be available after March 31, 2024. All MWS developers must migrate to Selling Partner API (SP-API) to avoid service disruptions. Refer to the Migration Hub for more information.
Whenever you are implementing a new process or changing an existing process, test it with a small number of items before trying it with large quantities. For example, if you begin sending items to Amazon's fulfillment network using the Inbound Shipment API section, test the process by sending in just a few items the first time. If everything works as expected, then try it with larger quantities. Likewise, if you begin creating your own item labels and shipping labels, test them with an inbound shipment that contains just a few items, even after getting your label samples approved by Amazon. If your first try is successful, then put your labels into production using larger quantities.
Note that you can practice with the operations of the Inbound Shipment API without actually sending any items to Amazon's fulfillment network. If you practice with the Inbound Shipment API in this way, please be sure to cancel any large inbound shipments that you create immediately after your test, or as part of your test.
Amazon recommends that you create listings for all of the items that you want to include in an inbound shipment plan before calling the CreateInboundShipmentPlan operation. After you have created listings for the items that you want to include in the CreateInboundShipmentPlan operation, include only the SellerSKU and Quantity request parameters when calling the operation. Do not include the ASIN or Condition request parameters.
For more information, see Shipping inventory to Amazon's fulfillment network.