To build a web application for Amazon sellers, you must first register as a developer. See
Registering as a
developer. On the last page of the registration workflow, make note of
your Developer ID, as you will need to provide this to sellers who want to use your
developer services or web application. You can get your Developer ID at any time by
going to the User Permissions page on Seller Central. For more
information, see Where do I find my identifiers
When your web application is ready, provide sellers with your Developer ID, which they can use
to authorize you for developer access to their selling accounts. A seller authorizes
you as a developer from the User Permissions page in Seller Central. For more
information, see I am a developer and I want to
develop Amazon MWS applications for sellers. What should I do?.
The seller provides you with the MWS Auth Token associated with
your developer account and their Seller ID. You can then make Amazon MWS requests on their behalf, using the seller's
identifiers and your developer credentials.
For further assistance with building Amazon MWS
applications, see Related Resources.