Unable to add customs sells.

[Kiraxarik]

Minecraft Version

1.21.1 (LTS)

Mod Loader

NeoForge

Describe the Issue

Creating a datapack to add new items to the market does not add items.

Logs

latest.log

[BlayTheNinth]

[13Oct2025 20:03:09.960] [Render thread/ERROR] [net.blay09.mods.farmingforblockheads.FarmingForBlockheads/]: Error loading Farming for Blockheads market category file at farmingforblockheads:market_categories/enchanted_books.json
java.lang.IllegalStateException: No key id in MapLike[{"item":"minecraft:book"}]

Use "id" instead of "item" in your market category json.

[Kiraxarik]

latest.log

Ok, I fixed that, and another one that got missed with the recipe. I'm not finding any errors in the log, and the item shows up in the market, but the market category don't show up and the preset isn't working for the item.

market_category
Enchanted_Books.json

market_preset
Enchanted_Books.json

recipe
Enchanted_Book.json

[BlayTheNinth]

• Make sure all your json file names are lowercase only, e.g. enchanted_books.json
• For ingredient objects (e.g. in the market preset), "item" should remain "item", not "id"
• The namespace of the category should match the namespace of your data pack
• The namespace of the preset should match the namespace of your data pack

Closing since thread has been moved to Discord