How to Set Durability:
To set the durability of a specific tool, use the following command:
/data modify storage <target> max_damage set value <value>
Copper Axe Example:
/data modify storage minecraft:copper_axe max_damage set value 256
Quick Configs:
To give all tools of a specific tier the same durability, use "tier/tool" as the target:
Golden Tier Tools Example:
/data modify storage golden/tool max_damage set value 320
Notes: