Handbells

A tool crafted with a Bell or alternatively offered by Toolsmiths in lieu of an ordinary Bell.

Right-click to shake the bell, illuminating mobs tamed or named by the Player with the Glowing Effect, much like how ordinary Bells reveal Illagers.

This could help find mobs the Player has lost track of. Whether it's a Wolf left behind in a cave, an Axolotl roaming freely in river, or an Allay lost in the Nether, all you need to do is shake the bell and look.