Some of the API endpoints, for example /master/tasks.json, will return bogus information if you query a non-leading master:
This is very hard for end-users to work around. For example if I query "which master is leading" followed by "leader: which tasks are running" it is possible that the leader fails over in between, leaving me with an incorrect answer and no way to know that this happened.
In my opinion the API should return the correct response (by asking the current leader?) or an error (500 Not the leader?) but it's unacceptable to return a successful wrong answer.