Minecraft wiki entry for Wandering_trader_farming, associated text: Wandering trader farming is the process of farming wandering traders for their trades, and then disposing them and their llamas to get leads and leather. It can be a very good farm to built since it is the only glitchless way to renewably farm items like sand, red sand and small dripleaf, however it will require several emeralds, so you might want to hook it up to a villager trading hall or raid farm.