Spine error: Couldn't find slot for skin
- spine-ts (web, Phaser, PixiJS)
Couldn't find slot hat for skin default.— SkeletonJson.readSkeletonData- spine-csharp (Unity)
Slot not found: hat— SkeletonJson.FindSlotIndex
A skin lists attachments under a slot name that the skeleton does not have. Skins are read after slots, and each slot key in a skin's attachments must match a slot exactly.
Why it happens
- A slot was deleted or renamed, and a skin still holds images for it.
- A skin merged or pasted from another skeleton with different slot names.
- A case or spelling difference between the slot and the key in the skin.
How to fix it
Find the slot name from the message in the skin's attachments. Rename the key to the real slot, add the slot to slots (it needs a bone), or delete the key if those images are no longer used. The Unity runtime reports this as Slot not found: … without the skin name, so search every skin.
Check your skeleton
The Spine JSON validator does not look for this one, but checks the rest of the file for the problems the runtime loads silently — slot colors, mesh data, deform keys, bone order. It runs in your browser.