JobBlocker allows you to block a workstation from being a villager job site. This lets you have builds containing lecterns, barrels, etc. without villagers walking around them and working there.
Right click with a JobBlocker Wand any villager workstation with the JobBlocker Wand to mark it as blocked. Any villager that attempts to claim that block as their job site will be immediately rejected. If any villager claimed this workstation beforehand, he will lose his profession.
Left click a workstation with a JobBlocker Wand to see if it is blocked. This will be shown in action bar. Check gallery for examples.
/jobblocker - gives you the JobBlocker Wand, needed permission: jobblocker.use.