[According to m0sa,][1] the search parameter behavior is by design: 

> It's just named badly. Consider thinking about it as hasAnswerWithScoreGreatherThanZero.

Naming aside, I actually prefer the current behavior, because it gives me more flexibility in search. I can combine `isanswered` and `hasaccepted` parameters to get any combination of "answer with positive score" and "accepted answer" I want:

* answer with positive score: yes, no, doesn't matter
* accepted answer: yes, no, doesn't matter 

If `isanswered` automatically included `hasaccepted`, the search possibilities would be fewer. 

So I think it's the help center that should be fixed. Until recently, the parameter was not documented there at all. After my request https://meta.stackexchange.com/questions/250626/the-isanswered-search-parameter-should-be-documented its description was added, but an incorrect one. 


  [1]: https://meta.stackexchange.com/a/250187/259867