Minecraft 1.18.1
Forge 39.0.89
Mod version 0.2.8

When taking the Smith job perk 'Enchantment from item to Book', placing a tool in an anvil along with literally any other object will give the enchanted book; no book required. This also makes it impossible to repair tools with their material or combine them.

This can be temporarily fixed by disabling the job perk.

This issue was fixed in version 0.3.0. 1.18.1 is discontinued.