>> an HTTP post to the collector doesn't have interesting semantics. So ditching add(List<>) will prevent mistaken assumptions.
No totally true.
The ChukwaHTTPSender is an implementation of the ChukwaSender interface and if you were using a JDBCCollector you will open a transaction, insert the list of chunks in batch mode then commit. I think that it could be the same for an HTTP post.
It best to be able to acknowledge at the HTTP post level rather than at each individual chunk, at least it gave us the flexibility to do it at this level.
So +1 for remove add(Chunk) and not ditching add(List<>) .
The next question is do we want to report any warning/error in a well defined Object so the collector can report that in a unified way.
Right now the HTTPSender is not using the HTTP response.