AttributeModify / NeoAttributeModify

Version 1.2.3 | Minecraft 1.20.1 Forge and Minecraft 1.21.1 NeoForge

Modify item attributes and related item behavior through datapacks. AttributeModify supports vanilla and modded attributes, mining overrides, durability changes, decorative item profiles, weighted quality data, and optional Curios or Accessories slots.

AttributeModify and NeoAttributeModify are distributed through the same CurseForge and Modrinth project pages. Install only the file that matches your Minecraft version and mod loader.

Available Versions

Mod	Minecraft	Loader	Java
AttributeModify	1.20.1	Forge 47	Java 17
NeoAttributeModify	1.21.1	NeoForge 21.1	Java 21

Forge and NeoForge files are not interchangeable.

Features

• Add, replace, set, or remove item attribute modifiers
• Remove a specific modifier operation without removing the others
• Override mining speed while preserving external speed multipliers
• Raise an item's harvest capability to vanilla or modded mining tier requirements
• Override durability and define custom durability triggers
• Disable functional behavior for decorative items without deleting unrelated player effects
• Roll weighted quality data during crafting, loot generation, or villager trades
• Generate datapack rules through an in-game editor
• Apply rules conditionally using NBT paths
• Support vanilla and modded items
• Apply changes in multiplayer environments
• Reload datapack rules using /reload
• Keep Curios and Accessories rule storage isolated

Requirements

AttributeModify — Minecraft 1.20.1

• Minecraft 1.20.1
• Forge 47.4.0 or a compatible Forge 47 release
• Java 17

Optional integrations:

• Curios 5.14.1+
• Accessories 1.0.0-beta.47+
• Apotheosis 7.4.8 and its required Placebo dependency

NeoAttributeModify — Minecraft 1.21.1

• Minecraft 1.21.1
• NeoForge 21.1.220 or newer
• Java 21

Optional integrations:

• Curios 9.5.1+
• Accessories 1.0.0-beta.47+

Both versions start normally when the optional integration mods are absent.

Datapack Layout

Place the datapack inside:

<world>/datapacks/

Attribute rule files belong under:

data/<namespace>/item_attributes/

Example structure:

MyAttributePack/
|-- pack.mcmeta
`-- data/
    `-- my_namespace/
        `-- item_attributes/
            `-- tools.json

Run /reload after changing datapack files.

Datapack Formats

The required pack_format depends on the Minecraft version.

Minecraft 1.20.1

Use datapack format 15:

{
  "pack": {
    "pack_format": 15,
    "description": "My AttributeModify rules"
  }
}

Minecraft 1.21.1

Use datapack format 48:

{
  "pack": {
    "pack_format": 48,
    "description": "My NeoAttributeModify rules"
  }
}

In-Game Editor

Each version provides its own client command.

Mod	Editor command	Generated datapack
AttributeModify	/attributemodify_editor	AttributeModify_Editor
NeoAttributeModify	/neoattributemodify_editor	NeoAttributeModify_Editor

The generated datapack is written into the current world's datapack directory.

Saving requires either:

• Being the owner of the singleplayer world
• Having permission level 2 or higher on a server

Support

Discord: https://discord.gg/NXVEtWqsnw