When my daughters were younger, my wife and I would go into our bedroom after work to spend some time away from them. They weren’t allowed to knock on our door or call to us except in an emergency. My younger daughter got around this by writing notes and slipping them under the door. We would generally play along and slip her answer back to her. Here’s an example:

It says, “Can I be done with my rice? I took 4 big bites. Circle yes or no.” We didn’t answer that one, probably because we’d already told her to eat ALL her rice.
Some questions were a bit trickier to answer, such as this one:

But you can see that we, as responsible parents, did our best.
She got you on the candy one. You just though it was cute, but she knew that “no” meant one piece and “yes” meant all she could eat.
Ha, ha, that’s great. :-)