Regarding "playing tricks" ... that requires some interpretation on our part. Tricks points to humor and humor requires a cultural context since different cultures find different things funny. Providing stimulii to assess our reactions ... most likely. Whether it is "humor" or not requires crawling out the limb a little farther.
I would recommend caution in interpretation of "jokes." I would recommend caution in returning "jokes". Could go badly wrong.
We have to make assumptions and we have to interpret, there's no progress without those, but we need to keep a clear eye on what it is we are assuming and what interpretations we are making so we don't slip up and allow them to become something else, something akin to doctrine or dogma. Their validity is part of what we need to test, it's not the basis for evaluating the results of the test.
MIB