Semiautomatic farms are farms in which the crop is harvested for you but you have to replant it. They are usually based on Water currents, which uproot plants.
Make a 7 long, 1 wide row of Jungle Logs and put Cocoa Beans on them.
Put Dispensers opposite the Cocoa Beans and fill them with Bone Meal. Add an activation system (a Button or Lever works well) for the Dispensers.
Put a Dispenser at one end of the Cocoa Bean row. Add a means of activation, making sure it's not linked to the bone meal dispensers. Put a Water Bucket in it.
Put a Hopper linked to a Chest at the opposite end of the row, making sure it's at the same level as the Cocoa Beans.
Turn on the Dispensers to make the Cocoa Beans grow with bone meal! Then, turn on the water dispenser to wash the beans into the hopper and chest! Take out the beans and replant them!