HTTP Response 500 - /NEPTUNE/CX_DYNAMIC_RESTAPI-NO_ENTITY_SETS_EVAL_POSITIVE
Cause
This error is related to insufficient authority of the client who wants to execute the API endpoint. The API Factory is secured in a very strict way to give you full control about which "Entities" can be executed.
Example
As a default an API Factory class is not executable at all. You will first need to enable it either with the Switch "unrestricted API Engine" set to "true" or via the assignment of sufficient Policies.
Solution
Enable the corresponding API Factory class either with the Switch "unrestricted API Engine" set to "true" or via the assignment of sufficient Policies. For more information, see API Factory - Policy