MWS API Limitations

Updated 2 years ago by Travis R

AccelerList, and all other 3rd party services, communicate with Amazon through Merchant Web Services (MWS) Application Programming Interface (API). There are some limitations to the information Amazon provides to third party service providers.

The key limitations are:

Restricted Categories – Amazon does not give AccelerList live information about a product being restricted until after the feeds have processed. This means that you have no way of knowing whether a product is restricted before listing it to a batch. The listings will not become active at Amazon, however, in order to avoid sending in something that you cannot sell, scan items with the free Amazon Seller App or lookup the item using the “Add A Product” feature in seller central. While it is not always 100% correct, it is the best way to check on your restrictions on products you intend to list on Amazon.

“Competitive” Offers – Amazon only shows items that are deemed “competitive” and not necessarily all lowest offers on a given product. AccelerList will show you the buy box offer, and several other “competitive” offers, but if you need to see a full look at the offers in any given marketplace, please view the prime comparison icon during product lookup.

Amazon annotated as a merchant on an ASIN – While AccelerList does try to make a very educated “guess” as to when Amazon is a merchant on a listing, it is not always 100% correct. Amazon does not provide details on merchant names, and therefore AccelerList is not 100% accurate when showing when and when not Amazon is a merchant on an ASIN.

Hazmat Review – The API prevents items from showing if a product is under Hazmat review during product lookup, although AccelerList does block items under Hazmat review while you are listing

Warehouse Splits – In private workflow, warehouses can change by the time you land on the FBA Shipping page, the warehouses maybe much different than your sort from the listing page. You can prevent this by creating your shipment within 48 hours, even it if it just a partial shipment and then starting new batch if you still have items you want to add to the existing working shipments you created with your partial.

Sub-categories – The API does not give sub-category specific commission information for all parent categories. The result is that commission amounts can be off because we can not see the sub-category specific commission rates.


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