Diamond picks have durability 1024, a vanilla diamond pick has 1561, is the difference intended? All the tools

There is also no config file for the client in the CONFIG folder. I found the server config file in the save folder.

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Diamond picks have durability 1024, a vanilla diamond pick has 1561, is the difference intended?

The Minecraft tool durability and the durabilities from this mod are completely unrelated.

There is also no config file for the client in the CONFIG folder.

This mod has no client config as there is nothing that is configurable on the client side.