Currently player/avatar has the omniscient knowledge of all item types that exist in the world, specifically, it shows in the item description:
screenshot of the fresh character

Recipes:

There are item types that are uncommon enough to assume that an average joe (random character) shouldn't know about their existence.
Note: that tracked set is different from the list of autolearned recipes (it's actually a superset of known recipes). E.g: player can know of something without the ability to craft it.
It should probably feed off from skills and proficiencies. Ideally, in JSON, you should be able to append alternate descriptions. e.g. a int 3 character sees a shillelagh as "big hurting stick" or someone with no knowledge of guns should only be able to tell a weapon is "handgun" or "rifle."
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It should probably feed off from skills and proficiencies. Ideally, in JSON, you should be able to append alternate descriptions. e.g. a int 3 character sees a shillelagh as "big hurting stick" or someone with no knowledge of guns should only be able to tell a weapon is "handgun" or "rifle."