Might of the Master. The following numbers increase by 1 when your proficiency bonus increases by 1: the bot's skill and saving throw bonuses (above), the bonuses to hit and damage of its fist attack, and the number of hit points restored by its Repair action (below). When you gain ability score improvement, the bot can have it's ability score improved, or it can gain a feat. When you reach 10th, and then again at 15th level, the bot can gain one skill, tool, language, or weapon proficiency.

Helpful. The bot can take the help action as a bonus action.

Robotics. If the mending spell is cast on it, it regains 2d6 hit points. If it has died within the last hour, you can use smith’s tools as an action to revive it, provided you are within 5 feet of it. The bot returns to life after 1 minute with all its hit points restored.

Force-Empowered fist.. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 1d4 + 2 bludgeoning damage plus 1d4 force damage.

Repair (3/Day). The magical mechanisms inside the bot restore 2d8 + 2 hit points to itself or to one construct or object within 5 feet of it.

Deflect Attack. The bot imposes disadvantage on the attack roll of one creature it can see that is within 5 feet of it, provided the attack roll is against a creature other than the defender. 

Whenever your bot uses its Deflect Attack, the attacker takes force damage equal to 1d4 + your Intelligence modifier.