It is not sentient (although Taryon talks to it like it is) and cannot act unless under Taryon's orders. In combat, it uses physical blows to attack smaller enemies or assists with physical tasks. The one action it can take on its own is a retaliation strike if an enemy attacks its ally within a few feet of itself.

Out of combat, it's basically a robot butler that carries Taryon's stuff and does small tasks he asks it.

Edit: forgot to add the other feature Doty has — he is programmed to say one word ("Tary") mostly so that he sounds like he's listening and having conversations