I recently asked a question regarding the identification of paper without feeling it.
Is applying a tool-related tag to a paper-question within the scope of those tags?
Or is paper not considered a tool? (at least in origami)
In this, and near all cases, paper should be considered a material and/or a medium. Tools are more for implements and machines. Paper isnt really either of those things.
I think paper on its own is enough for your question as you are asking about paper specifically (As far as the scope of this Meta question is concerned). I don't foresee many material-identification questions.
If your want to make a case for it I would suggest we try to come up with some more examples for its justification.
I think that question could use some work as well but that will be covered in the question itself.