Checking the CaptureResponse API for Pega Marketing Real-Time Containers, we have observed that while there is a way to specify the response of a customer to an Offer (Accepted, Rejected,...) by means of the request field "Outcome", there is no way of, for example, specifying the reason for rejecting an offer (when Outcome = "Rejected").
Is there any way to expand the OOTB APIs to include this or further information as additional request/response fields?
The OOTB CaptureResponse API can be extended but I would first be interested in your use-case. Is this in the context of a Call Center where an agent can ask the customer? How are you planning to use this data?