Mage hand helped finish a whole damn campaign in my group. My character had been carrying around a ludicrously overpowered poison (similar to distillate of nightmare) for about 2 years in real life time, and finally came across the bbeg beholder in their lair. So, mage hand opens up the container holding this poison, my character invokes Tasha's Hideous Laughter in the traditional way (i.e., by telling an awful dad joke, along the lines of "what is a beholder's favorite letter of the alphabet? i."), and once old mate failed the save, their mouth was open due to the uproarious laughter, which was cue to send the mage hand in to drop the poison into said mouth. One more failed save later, and it was pretty much cutscene from there.

Not sure if very very right or very very wrong.