[artmageddon]

> > is the list sorted

If I were the interviewer, this question would almost make me dock points off of the interviewee

Why? Knowing that can be a useful filter to reduce the search time and space, assuming whole numbers only.

[yankjenets]

Because the answer should be an obvious "no it is not guaranteed to be sorted".

If the answer is yes the input is sorted, then that context should have been given in the original prompt as it is a completely different question.

[artmageddon]

It is, but some interviewers can be intentionally vague.