Ignore non-existent item tags

Ignore non-existent item tags

A tiny Fabric utility mod for fixing the crash: java.lang.IllegalStateException: Trying to access unbound tag

What it does

This mod injects into HolderSet$Named.contents(). When a recipe ingredient references a tag that does not exist at all (unbound tag), instead of crashing the server/world loading, it:

• Skips that broken ingredient, continues loading recipes and world
• Prints a warning with the broken tag ID in the chat bar

⚠️ Important disclaimer This is a workaround, NOT a real fix. It only prevents the crash. The recipe that depends on the missing tag will not work. You still need to find which mod / datapack defines that broken recipe.

Environment

• Loader: Fabric
• Dependencies: No other dependencies except fabric api
• Side: Server + Client (required on both for single-player)
• No config, no GUI, no extra items/blocks. Just install it.

Tips

1. After entering your world, check the chat bar for warning messages starting with [Warning]Unbound tags found: . It tells you exactly which tag is missing.（If there isn't such warning, nothing happens then.)
2. You can install Spark mod, and use /spark recipes to find out which recipe caused the broken tag.
3. If you want a proper fix: update the problematic mod, remove it, or add a datapack to define the missing empty tag.

Ignore non-existent item tags模组

一个极简 Fabric 补丁模组，专门解决这个经典崩溃：Trying to access unbound tag（访问未绑定标签）

原理

通过 Mixin 拦截 HolderSet$Named.contents()。 当配方成分引用一个完全不存在的标签时，游戏不再直接崩溃，而是：

• 直接加载配方和世界
• 在游戏聊天栏打印警告，输出损坏的标签ID

⚠️ 重要提醒（一定要看）

这只是绕过崩溃的补丁，不是根治修复！ 它仅仅让你能进存档。依赖这个缺失标签的配方会失效、无法使用。 你后续仍然需要排查到底是哪个模组/数据包写了错误配方

使用方式

直接放入 mods 文件夹，客户端和服务端都要装，单人存档必须装在客户端。 无配置界面、无物品方块、无需任何设置。

使用建议

1. 进存档后查看聊天栏，会出现 [Warning]Unbound tags found: 开头的警告，告诉你缺失的标签名称（没有则说明无事发生）
2. 可以安装 Spark 模组，用 /spark recipes 定位是哪个配方引用了坏标签
3. 根治方案：更新问题模组、移除它，或者写一个小型数据包定义这个空标签