Finally you don't have to go to a mob farm and kill mobs to repair your Mending tools anymore!
Just put the tool you want to repair into your off hand and sneak.
This way you use your own level to repair your mending tools.
It will automaticaly stop when the tool is fully repaired.
Installation:
1) Open your world's folder
2) Go to world_name/datapacks/
3) Paste the DeathLocation.zip here
4) Open world_name and type /reload