UnionClef

Letting agents loose in block game.

An open platform for building AI agents that play Minecraft — pathfinding, combat, survival, multiplayer. The goal is to make it easy for researchers, developers, and tinkerers to plug their agents into the game and see what happens.

Built by merging altoclef, shredder, and tungsten into a single codebase. No submodules, no pre-built JARs, no tears.

What's inside

Module	What it does
altoclef (root)	Autonomous bot — speedruns, PvP, SkyWars, Python scripting via Py4J
shredder/	Pathfinder v2 — fork of baritone with WindMouse camera, tungsten integration, human-like movement
tungsten/	A* pathfinder that doesn't break blocks — complex parkour, follows players, PvP movement
baritone/	Legacy pathfinding code, kept as reference. Replaced by shredder

Minecraft 1.21 / Fabric / Java 21

How to build & run → | How to release → | Multi-version → | Python scripting →

Features

(table is not ready yet, TODO. Functions more than this presented. TODO find more organic, suitable and sexy form for this features table)

Feature	Description	Ready
MLG
Enderpearl clutch	TP with enderpearl when pursue target. Save self with enderpearl when dropped from edge.	3/3 ✅
Arrow dodger	Epic incoming arrow dodging. If has shielf - uses it.	1/1 ✅
@test mace	😎	1/1 ✅
#bridgingMode jump	Super-fast bridging. (To cancel, you can change mode to slow, standart or back-jump)	1/3 ❌ TODO
PvP
Attacking bot @punk	Handles close target battle. Wind-mouse based rotations. Brokes shields (axe). Uses own shield. Combines ranging and melee attacks automatically, pursues targets. Using mace from the height	3/3 ✅
Shooting bot @shoot	Handles ranged target battle with 2 types of angle (rapid-fire, sniper, artillery)	3/3 ✅
Pursuing bot	Pursue parkouring targets. Slow for now.	2/3 ⚠️
Minigames
Skywars @game sw	SkyWars (fails exploration, buggy)	3/5 ⚠️
Skywars @game bw	BedWars (only bed protect)	3/5 ⚠️
Skywars @game skypvp	SkyPvP (on one server, but non-redactable spawn)	4/5 ✅
Skywars @game mm	MurderMystery	5/5 ✅
Building
@grave <text>, @sign <text>	New structures to build	2/2 ✅
Privated regions support	Temporal block placement and removal locks	4/5 ✅
@schematic <schematic>	Schematic integration	0/3 ❌ TODO
Multiplayer
Autologin (@set multiplayer_password <password>)	Autologin and autoregister	3/3 ✅
Agentic
Python integration	Py4J configurable two-way interface. Port configures via @set pythonGatewayPort <port>. Supports multi-instance launching. Rich contextual and method base (see adris.altoclef.Py4JEntryPoint class) for agents, including live-screenshot support.	3/3 ✅
Agentic commands	@check_block, @check_player	3/3 ✅
Agentic MCP server	MCP for AI agents endpoint on java-side	0/3 ❌ TODO
Comfort
Command suggestions	Rich chat commands suggestions @help	1/1 ✅
Monorepo structure	Multi-versioned structured mono-repo with easy-to-work with any of integrated mod	1/1 ✅
Removed naughty prints from baritone		1/1 ✅

Vote for the new features, report for bugs in the issues.

Quick start

1. Drop the latest JAR from releases into your Minecraft mods/ folder and launch with Fabric

   Ensure you have the correct Minecraft version for the release you download

2. Type @help in chat for the list of commands

Development

Quick start for development — clone the repo, build, and run:

git clone https://github.com/3ndetz/unionclef
cd unionclef
gradlew compileJava     # compiles everything
gradlew runClient       # launches Minecraft

See docs/DEVELOP.md for debug setup, hot-swap, and troubleshooting.

Demo

SkyWars bot in action

Looting chests

Gapple & EnderPearl

Kill & Loot

Bow

Tungsten pathfinding

Pathfinder that can't build/break blocks and looks like a NASA computing program.

Project structure

unionclef/
├── src/main/java/          altoclef source (bot logic, commands, tasks)
├── src/main/resources/     fabric.mod.json, mixins, assets
├── shredder/               pathfinder v2 (fork of baritone + tungsten bridge)
│   └── src/main/java/      shredder code (baritone.* packages)
├── tungsten/               tungsten source (A* movement, player following)
│   └── src/main/java/      tungsten code
├── baritone/               legacy pathfinding (kept as reference, not used)
│   └── src/main/java/      original baritone code (remapped to yarn)
├── scripts/                python scripting via Py4J (uv project)
├── root.gradle.kts         root build config
├── gradle.properties       versions & settings
└── docs/
    ├── DEVELOP.md          build & run instructions
    └── SCRIPTS.md          python scripting guide
├── README.md               you are here
└── TODOS.md                project TODOs and roadmap

Fork History

altoclef

1. Origin: gaucho-matrero/altoclef →
2. Fork: MarvionKirito/altoclef →
3. Fork: MiranCZ/altoclef (multi-version support, bug fixes) →
4. Fork: 3ndetz/autoclef (multiplayer, SkyWars, Python bridge) →
5. Merged into: unionclef

shredder

Fork of baritone, rebuilt as the primary pathfinder. Keeps baritone.* packages for API compatibility but adds WindMouse camera smoothing, human-like movement entropy, and a tungsten bridge that delegates complex parkour segments (no block breaking/placing) to tungsten's A* executor.

1. Origin: cabaletta/baritone (by leijurv & Brady) →
2. Patched by altoclef maintainers (GauchoMatrero → MiranCZ → 3ndetz) →
3. Remapped mojmap → yarn →
4. Forked as shredder with WindMouse + tungsten integration →
5. Merged into: unionclef

baritone (legacy)

Original pathfinding engine. Kept in the repo as reference code — all active pathfinding now goes through shredder.

1. Origin: cabaletta/baritone (by leijurv & Brady) →
2. Remapped mojmap → yarn & merged into: unionclef →
3. Superseded by shredder

tungsten

1. Origin: CaptainWutax/Tungsten →
2. Fork: Hackerokuz/Tungsten (crash fixes, followPlayer) →
3. Fork: 3ndetz/Tungsten (altoclef integration) →
4. Merged into: unionclef

License

GPL-3.0 — see LICENSE.

Incorporates code from: baritone/shredder (LGPL-3.0), altoclef (MIT), tungsten (CC0-1.0).