Minecraft wiki entry for Development_versions, associated text: recipeBook: Now a compound tag (was a string) containing recipe book information
isFilteringCraftable: Becomes 1 if the player has enabled the "Show Craftable" feature in the recipe book.
isGuiOpen: Checks if the player has left the GUI open.
unlocked
recipes: Contains information about all recipes the player has seen.
displayed: Checks if the player has tried out the recipe in the recipe book before (by clicking it/viewing it)