Q:

What information is appropriate to ask from a post to help contextualize?

In this question there arose the issue of whether to take answers from various sources.  I haven't seen the question of questions from students (obviously, presuming that a given question is in fact about math education).  However, there has been some asking questioners about student status recently, which leads me to ask:

What information is appropriate to ask from questioners on this specific site?

Obviously on many sites it wouldn't be appropriate to ask job status, but given that this one is about teaching, it is reasonable that we ask the country people teach in, what age level, etc.  On the other hand, unless the question is about gender or ethnicity (which they could be) probably ordinarily it wouldn't be appropriate to ask about this.
Although this question is motivated by asking whether questioners are students (and that raises the related question of whether we aren't all students!), I figure it would be helpful to have a big list of potential things to ask questioners about which mods and/or contributors think would be clearly off-limits or clearly on-topic.

A:

Honestly, I do not think it will be helpful to have a list.
It is a general principle that focus should be on the post, and not on the user. Thus, who or what specifically the person controlling the account is in actual reality, should not really be a concern. In any case, usually we cannot check the veracity of what we are told, and have to take on faith whatever we would be told. 
That said, in the context of a question details can be important to make the question sufficiently precise to be meaningful and answerable. In such a case I think it is appropriate to indicate that the lack of contextual details prevents the question from being answerable. It is then up to the person asking to provide such details (or not).
It is relevant to note that the "personal" details they might provide do not even have to match reality. There just needs to be something to scope the question reasonably well. 
Phrasings of requests for additional context can take this into account. Say, if there is a question on the feasibility of not using a common textbook but going by ones own notes, compare:  

I think to answer the question it is relevant to know how much prior teaching-experience (in this and related subjects) the instructor has.
Since when do you teach?

Depending on the phrasing of the post, the first might seem artificial, but the following might be a middle ground. 

I think to answer the question it is relevant to know how much prior teaching-experience (in this and related subjects) you have.

