Describe the feature

I am completely lost on how to make my book work for my modpack, to the point where I even tried packaging it within a mod just to get it to work. My specific issue is with the category system, I don't know what I'm supposed to add as a prefix for my categories when I put them into an entry. I almost feel like it's impossible to make a book because I've tried literally everything.

My modpack ID is ASTARPG in all caps, I have placed the entry both within and outside a folder, however I believe it has to be placed within the folder for it to work (this is not on the documentation!). I believe I need a colon for the prefix, but it states I have a non a-z character in the namespace (ASTARPG:survival).

My book name is asta_rpg, so I tried using that as a prefix. So I launch using asta_rpg:survival as the name, this gives the error "flint tool does not have a valid category", I'm assuming the book name is not supposed to be used as the prefix.

Then I did

patchouli_books.zip

just survival as the category and it gives the same error "flint tool does not have a valid category"

Additional context

No response

Found out it was supposed to be patchouli according to the documentation. Could this be clarified here to avoid confusion? (if the book is loaded from the minecraft.net folder (i.e modpacks).