A prank is only funny if everyone involved gets to laugh at the end.

Comedy needs the target in on it, otherwise the laughter is at somebody rather than with them. Intent does not settle this. The test is simple and it happens afterwards, in whether the person can join in without pretending. If they have to perform being fine, it was not a joke to them.

Before you go ahead, picture the moment right after, with them standing there. If the image needs them to be a good sport, that is a sign. Pick the version where they get to laugh too.