I’m trying to connect Contentful with Chatfuel and everything needs to be structured according to their setup. Can I transform or define a custom schema for the CDA API responses, right?
https://help.chatfuel.com/facebook-messenger/plugins/json-plugin/
Heyo. 
It’s currently not possible to define a custom schema for the JSON responses.
Right now the Content Delivery API supports the include and select operator.
Using include you can define the level of linked entries you went to recolve.
Using select you can choose which fields to return from the entity and save some bytes on the wire.