Items / Recipes
To do such a thing, you would have to save all the data fetched via the API in a DBMS with links between the tables “items” and “recipes” for example.
The data provided by this API is coming directly from the game, but I don’t think they would add additional computing like this on their servers.
I don’t see why not. They already support passing in a collection of item ids in their trading post api and their trading post api also allows you to search via their search filters, which includes item type.