open-hands-lib
Open Hands Lib is a library that lets each hand track its own attack and mining cooldown, letting content mods choose which hand acts.
What it does
The library gives each hand its own cooldown timer for melee attacks and for block breaking, so a weapon in one hand does not share a timer with the other. Hand selection is handled through the ResolveAttackHandEvent and ResolveMiningHandEvent events, which let a content mod decide which hand should attack or break a block, for example by alternating hands or picking the better weapon. Damage enchantments, weapon effects, tool harvest checks, speed and durability all follow the hand the library resolves.
Open Hands Lib runs on both client and server, so the server and every player need it. It is published for Fabric and NeoForge for 1.21.1 only, and it depends on Fabric Language Kotlin on Fabric and Kotlin for Forge on NeoForge. Duelist's Glove requires it. The code is not open source and is released under All rights reserved.
Key features
Independent hand cooldowns
Each hand keeps its own cooldown, and an attack lands only when the swing has reached full charge.
Attack hand resolution
The ResolveAttackHandEvent lets a content mod pick which hand strikes, such as alternating hands or choosing the stronger weapon.
Mining hand resolution
The ResolveMiningHandEvent chooses the hand for breaking blocks, and a per-block session cache holds that choice until breaking stops.
Custom mining conditions
registerMiningEnableCondition lets a mod define when the mining logic activates, and combat activation can be registered the same way.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Requirements
Dependencies declared by the latest file for each loader.
Required 1
Required by 1 mod
Use cases
Who it’s for: Developers of content mods that handle weapons, tools or block breaking who need per-hand timers and hand selection. Players use it through the mods that depend on it, such as Duelist's Glove.
How it compares
Hand Swap is a Fabric client-side only mod released under All rights reserved and published for 1.21 – 1.21.11, so it changes nothing on the server. Fast Tool Switching is open source under the MIT License, runs on client and server on Fabric and NeoForge, and is published for 1.21 – 26.1. TorchPlaceMod is a NeoForge mod for 1.21.4 – 1.21.5 that is optional on either side and released under the MIT License.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| open-hands-lib | Fabric and NeoForge | 1.21.1 | Client and server | 2026-06-28 |
| Hand Swap | Fabric | 1.21 – 1.21.11 | Client-side only | 2026-04-19 |
| Fast Tool Switching | Fabric and NeoForge | 1.21 – 26.1 | Client and server | 2026-03-25 |
| TorchPlaceMod | NeoForge | 1.21.4 – 1.21.5 | Client or server, optional | 2025-04-29 |
Questions
Does Duelist's Glove need Open Hands Lib?
Do the server and players both need Open Hands Lib?
Which loaders does Open Hands Lib support?
In the catalog
open-hands-lib is one of 3,514 Library mods on ModsFinder, and one of 2,348 Library mods for Fabric. 32,366 mods support Minecraft 1.21.1.
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What the author says
Per-hand melee cooldowns and mining for NeoForge content mods. A NeoForge library that splits attack and mining logic across main hand and off hand. Each hand gets its own cooldown timer; your content mod decides when the system is active and which hand to use.
Official listing
- Modrinth page
- modrinth.com/mod/open-hands-lib
- Owner
- ThrowNewError
- Published
- 2026-06-08
- Updated on Modrinth
- 2026-06-28
- Facts verified
- 2026-10-15