14 May 2019

Added the lastModifiedBy and createdBy fields to many representations in the API. These fields add change history information for API calls to these resources as of 2019-02-01. Resources created or last modified before 2019-02-01 will not contain these fields. The fields only track changes from direct API calls by the Merchant Center or client applications. The fields may not track changes from the Admin Center, or from internal background services, like product discount or inventory updates.

Client applications can also use a new HTTP header, X-External-User-ID, when making API calls to track changes initiated by a specific user's actions. The lastModifiedBy and createdBy fields return this ID if it is provided. Do not pass personally identifying information using the X-External-User-ID header. See Client Logging for more information.