My character is a level one high elf rogue, so I picked mage hand as his high elf cantrip. When he gets to level three, I plan on picking the Thief archetype. Can he use the fast hands bonus action to control the mage hand that he cast on a previous turn?
I think he should be able to because fast hands allows for the "use an object" action and I can't think of what other type of action controlling mage hand would be.
Mage Hand's description reads:
You can use your action to control the hand. You can use the hand to manipulate an object, open an unlocked door or container, stow or retrieve an item from an open container, or pour the contents out of a vial.
Fast Hands:
Starting at 3rd level, you can use the bonus action granted by your Cunning Action to make a Dexterity (Sleight of Hand) check, use your thieves’ tools to disarm a trap or open a lock, or take the Use an Object action.
Presumably, this newfound dexterity is proper to the Rogue (i.e., the physical prowess of the PC), whereas Mage Hand is based on mental effort and the limitations of the spell. Hence, without a houserule, I don't think you can control Mage Hand using a bonus action.
As othniel2005 said, you would have to pick the Arcane Trickster archetype for that.
Mage hand requires using your action to control it.
You can use your action to control the hand. You can use the hand to manipulate an object, open an unlocked door or container, stow or retrieve an item from an open container, or pour the contents out of a vial. You can move the hand up to 30 feet each time you use it.
That means it's an action. generally unless something specifies bonus action in 5e, it requires an action to do (with the explicit exclusion of very minor things).
Fast hands does nothing to change this action economy as it only applies to "use an object" Mage hand is not this as it requires a full action to use.
