My example was the
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http://us.battle.net/api/wow/item/12838
But looking at the information, there's nothing in there about the materials that the recipe needs to make the item.
In fact, there's no reference to the created item at all!
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There is a reference to a spell, 16994, and the Arcanite Reaper data refers to spell 16994, but 16994 is not an item, (
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Is that going to be made available? Some way to derive the mats for a crafted item?