You are able to order AI-controlled partner characters
to use or hand over items during the course of the game.

ASK TO USE

Highlight a partner's item and select it with the X button.
Then, select the ASKTOUSE command and press the X button again.
In this way, you can order them to use that item.

Of course, there are some instances when this command cannot
be followed due to the nature of the item in question.