Excellent project! 10/10 recommended. It really stops duping. Needed for every decent server. Because minecraft is a game made to have bugs, so we need external solutions like this.

This does seem really promising! I never ask questions in reviews but, I know you stated it injects the item with a unique uuid when given. So I assume that all new keys must be given through the command, wouldn't this cause the keys to not stack when generating the same keys with a different ID?

Looks promising, could you add the function that the key already exists instead of having to create it? I have my key made with the ExcellentCrates plugin