Why a 2xx body is not an offer's details, or undefined when it is: the detail
endpoint answers a JSON array of offer records (one, for one id), each an object
with an id. An empty array, {}, null or an error object is not an answer
(an unknown id is a 404).
Why a 2xx body is not an offer's details, or
undefinedwhen it is: the detail endpoint answers a JSON array of offer records (one, for one id), each an object with anid. An empty array,{},nullor an error object is not an answer (an unknown id is a 404).