/summon villager ~ ~ ~ {VillagerData:{profession:mason,level:5,type:plains},PersistenceRequired:1,CustomName:"\"Glass Maker\"",Offers:{Recipes:[{buy:{id:emerald,Count:1},sell:{id:glass,Count:4},maxUses:16},{buy:{id:emerald_block,Count:1},sell:{id:glass_pane,Count:64},maxUses:16},{buy:{id:sand,Count:64},buyB:{id:emerald,Count:1},sell:{id:glass,Count:64},maxUses:16}]}}