Villager workers.

They have to harvest all crops Wheat, Carrot, potatoes, ... but also cactus, sugar cane and cocoa if possible.

The will be spawned with a command and the workers will be bound to a player.

Right clicking the worker will open a gui where you can chose for the workers inventory or his upgrade menu where you can upgrade the delay between crop harvests and walk speed.

Also impotant is a limit / plot

So for short:

Right click -> inventory and upgrades
harvest crops + cactus, sugar and cocoa.
Has to work for a 120 x 120 area