Here is a sample question. In practice the IDs of those questions are unknown. But the tags are known (so I can use them in the search API).

http://stackoverflow.com/questions/32701251/documentdb-the-input-name-is-invalid-ensure-to-provide-a-unique-non-empty-str

Here is some detail information about the question/answer.

Question:

      Last activity time: 22 Sep 2015 06:37:51 GMT

Accepted answer:

      Last activity time: 22 Sep 2015 06:37:51 GMT
      Accepted time:      Around 22 Sep 2015 17:00:00 GMT

The last activity time of question/answer is not changed when the answer is accepted. So how to monitor if an answer is accepted by StackOverflow APIs (which only take creation time or last activity time)?