HIT references using RequesterAnnotation

When building processes that leverage Amazon Mechanical Turk (Mechanical Turk), it's often valuable to keep track of identifiers associated with the data in each HIT, particularly when handling HIT responses via notifications. For example, you might want to associate your HITs with a record in a database such as Amazon DynamoDB, and want your HIT to reference the primary key of the record.

The RequesterAnnotation attribute is a useful option for tracking these references. When you create a HIT using CreateHIT or CreateHITWithHITType, you can provide a RequesterAnnotation field that contains arbitrary data about each HIT. Although it is limited to 255 ASCII characters, this is generally adequate to capture identifiers that denote the origin of your data. The data provided here is only visible to the requester who created the HIT.

When you receive a notification that a HIT has been completed, you can use the GetHIT operation to retrieve the RequesterAnnotation. The identifier captured in the RequesterAnnotation can then be used to make updates in your database or other systems.