Minecraft Dedalus MCP

LAN-oriented Minecraft MCP stack: Python MCP server + Node Mineflayer bridge. Control a bot via the Dedalus agent or in-game chat as natural language commands.

New in v2: Skill library, multi-step planning, persistent world memory, freeform building from natural language, smelting/furnace automation, error recovery with retry, and a creative/survival mode toggle.

Quick start (one command)

Get everything running and command the bot from in-game chat:

1. Open Minecraft Java Edition, start a world, and click Open to LAN. Note the port (e.g. 61246).

2. Expose your MCP server so the cloud agent can reach it (required for chat commands):

   ngrok http 8000

   Copy the https://... URL (e.g. https://abc123.ngrok.io).

3. Run the one-command launcher (bridge + MCP server + join game + chat agent):

   export DEDALUS_API_KEY=your_key_here
   uv run python run_live_chat.py --join-host 192.168.68.70 --join-port 61246

   Use your machine's LAN IP for --join-host (or 127.0.0.1 if the world is on this machine). Use the port shown in-game for --join-port. Put MINECRAFT_PORT and MINECRAFT_HOST in .env to avoid passing --join-* each time. Add --auth offline to skip the Microsoft login (recommended for LAN worlds).

4. In Minecraft chat, type natural language commands. Examples:

   • mine 10 dirt

   • go to the tree

   • build a 5x5 house with oak planks

   • attack the zombie

   • switch to creative mode and give me 64 diamonds

   • create a plan to get iron tools

What this project is

• Python MCP server – Exposes 60+ Minecraft bot actions as MCP tools (move, mine, place, attack, craft, chat, plan, remember, build, smelt, and more). Built on dedalus_mcp.

• Node bridge – Connects to a real Minecraft (Java) client via Mineflayer. Handles pathfinding (including breaking/placing blocks in the way), digging, placing, combat, inventory, smelting, and slash commands.

• Simulation mode – Test the stack without a live game (simulated world and tools).

• Skill library – Save and reuse multi-step tool sequences (Voyager-inspired).

• Multi-step planner – Decompose goals into checkpointed execution plans.

• World memory – Persistent storage of locations, resources, and structures across sessions.

• Creative/Survival modes – Creative mode unlocks teleport, give, fill, summon, time, weather. Survival mode keeps legit pathfinding and resource gathering.

• Freeform building – Describe structures in natural language (house, tower, bridge, farm, stairs, fence, pool, platform, pillar).

• Error recovery – Automatic retries with alternative positions and resources when tools fail.

• Autonomous survival mode – Say "start autonomous" in chat and the bot plays the game on its own (inspect → plan → execute → learn). Say "stop" to return to command mode.

Requirements

• Python 3.10+ (e.g. via uv)

• Node 20+, npm 10+

• Minecraft Java Edition for real LAN play (world opened to LAN, or a server)

• Dedalus API key for the agent (DEDALUS_API_KEY in .env or environment)

• ngrok (or similar) if you want the cloud agent to respond to in-game chat

Setup

uv sync --extra dev
npm --prefix bridge install

Copy the example env file and fill in your values:

cp .env.example .env
# Edit .env: set DEDALUS_API_KEY, MINECRAFT_PORT (e.g. your LAN port), etc.

Environment variables (.env format)

Ways to run

1. One command: bridge + MCP + join + chat agent

export DEDALUS_API_KEY=your_key_here
uv run python run_live_chat.py --join-host YOUR_LAN_IP --join-port LAN_PORT --agent-mcp-url https://YOUR_NGROK_URL/mcp

2. Manual: bridge + MCP server in separate terminals

Terminal 1 – Bridge

npm --prefix bridge run start -- --listen-host 0.0.0.0 --listen-port 8787

Terminal 2 – MCP server

uv run python -m minecraft_dedalus_mcp.server --host 0.0.0.0 --port 8000 --bridge-url http://127.0.0.1:8787

Terminal 3 – Join game

uv run python run_join_game.py --host YOUR_LAN_IP --port LAN_PORT

3. Simulation mode (no Minecraft)

export DEDALUS_API_KEY=your_key_here
uv run minecraft-dedalus-run-sim

MCP Tools (60+)

Core Actions

Planning & Intelligence

Creative Mode (requires set_mode('creative'))

Freeform Building

Describe a structure in natural language with build_from_description:

uv run python run_tool.py build_from_description '{"description": "a 7x7x5 house with a door", "origin_x": 10, "origin_y": 64, "origin_z": 10, "material": "oak_planks"}'

Supported structure types: house, cottage, cabin, tower, turret, wall, bridge, platform, floor, stairs, steps, fence, enclosure, pool, farm, pillar.

Dimensions: Include WxLxH (e.g. 5x5x4) in the description for custom sizes. Defaults to 5x5x4.

Multi-Step Planning

Create plans that decompose goals into tool-call steps:

# Create a plan
uv run python run_tool.py create_plan '{"goal": "get stone tools"}'

# Check status
uv run python run_tool.py get_plan_status '{"plan_id": "abc123"}'

# Get next step to execute
uv run python run_tool.py get_next_plan_step '{"plan_id": "abc123"}'

Built-in plan templates: gather_wood, get_stone_tools, get_iron_tools, build_shelter, hunt_food, explore_area, prepare_nether.

Skill Library

Save reusable tool sequences and retrieve them by keyword:

# Save a skill
uv run python run_tool.py save_skill '{"name": "early_game", "description": "Get wood, craft tools", "tool_sequence": "[{\"tool\": \"mine_resource\", \"args\": {\"name\": \"oak_log\", \"count\": 4}}]", "tags": "early,tools"}'

# Find skills
uv run python run_tool.py find_skills '{"query": "wood crafting"}'

Creative Mode

Switch to creative mode to use god-mode commands:

# Switch to creative
uv run python run_tool.py set_mode '{"mode": "creative"}'

# Teleport instantly
uv run python run_tool.py teleport '{"x": 100, "y": 80, "z": 100}'

# Give items
uv run python run_tool.py give_item '{"item": "diamond_block", "count": 64}'

# Fill a volume
uv run python run_tool.py fill_blocks '{"x1": 0, "y1": 64, "z1": 0, "x2": 10, "y2": 64, "z2": 10, "block": "gold_block"}'

# Switch back to survival
uv run python run_tool.py set_mode '{"mode": "survival"}'

Creative tools return errors if called while in survival mode. The bot retains its pathfinding, planning, memory, and skill capabilities in both modes.

Autonomous Survival Mode

The bot can play the game on its own — proactively inspecting the world, setting goals, planning, executing, and learning. It only activates when you tell it to, and stops on command.

From in-game chat

start autonomous     → bot starts playing on its own
stop                 → bot stops and waits for commands
mine 10 dirt         → any direct command also stops autonomous mode
start autonomous     → resume autonomous play

Trigger phrases: start autonomous, play on your own, survive, do your thing, autoplay. Stop phrases: stop, pause, halt, wait, come here.

How it works

Each autonomous cycle:

1. Inspect — calls recommend_next_goal to decide what to do

2. Plan — the LLM agent sees the goal + all 60+ tools and decides its approach

3. Execute — runs up to 25 tool calls per cycle (mine, craft, build, fight, smelt, etc.)

4. Learn — saves locations, resources, skills from successful sequences

5. Repeat — waits 5 seconds, then starts the next cycle

The bot announces what it's doing in chat so you can watch. Rate limits are handled automatically (pauses and retries).

Standalone demo (no chat polling)

uv run python run_demo_autonomous.py

Press Ctrl+C to stop.

Demo Scripts

Run any demo (with bridge + MCP server running):

uv run python run_demo_skill_library.py
uv run python run_demo_creative.py
uv run python run_demo_full_agent.py

Persistent Data

The MCP server stores data in MINECRAFT_MCP_DATA_DIR (default .minecraft_mcp_data/):

Data persists across server restarts. Delete the directory to start fresh.

Project layout

bridge/                         Node Mineflayer bridge (real + simulate)
src/minecraft_dedalus_mcp/
  ├── server.py                 MCP server + 60+ tool definitions
  ├── bridge_client.py          HTTP client to bridge
  ├── models.py                 Pydantic models
  ├── constants.py              Domain constants
  ├── playbook.py               Survival goal recommendations
  ├── skills/
  │   └── store.py              Skill library (save, find, replay)
  ├── planning/
  │   ├── planner.py            Multi-step task planner with checkpoints
  │   └── blueprints.py         Freeform building (NL → block plans)
  ├── memory/
  │   ├── world_memory.py       Persistent world knowledge
  │   └── session.py            Session action history
  ├── modes/
  │   ├── base.py               Game mode manager
  │   ├── creative.py           Creative mode actions
  │   └── survival.py           Survival mode helpers
  └── recovery/
      └── retry.py              Error recovery with retry strategies
run_live_chat.py                One-command launcher
run_chat_agent.py               Chat polling + agent
run_demo_*.py                   Demo scripts for each capability
tests/                          Pytest (e2e with sim bridge)
docs/research.md                Research notes

Troubleshooting

• Microsoft login prompt blocks the bot — Pass --auth offline to skip Microsoft authentication entirely. This works for LAN worlds and offline-mode servers. See Offline auth below.

• Agent says "MCP server unavailable" — Use ngrok and pass --agent-mcp-url.

• ENETUNREACH or ECONNREFUSED — Wrong host/port or game isn't open to LAN.

• mine_resource returns mined: 0 — Block name mismatch. Use inspect_world to check names.

• Creative tools return "requires creative mode" — Call set_mode('creative') first.

• Smelting fails — Ensure a furnace is placed nearby and fuel + items are in inventory.

Offline auth (skip Microsoft login)

By default, run_live_chat.py and run_join_game.py use --auth microsoft, which triggers a Microsoft account login flow. If you're playing on a LAN world or an offline-mode server, you can skip this entirely:

# One-command launcher
uv run python run_live_chat.py --auth offline --join-host 192.168.68.70 --join-port 61246

# Manual join
uv run python run_join_game.py --auth offline --host 192.168.68.70 --port 61246

The --auth offline flag tells Mineflayer to connect without a Microsoft/Mojang account. The bot will join with whatever --username you specify (default DedalusBot). This is the easiest way to get started on a local LAN world.

Limitations

• Simulation mode tests tool flow, not real Mineflayer physics.

• Freeform building generates deterministic blueprints from keywords; truly novel shapes require extending blueprints.py.

• Creative mode requires the bot to have operator permissions on the server for slash commands.

• Smelting waits a fixed time for output; very large batches may time out.

• Skill library uses keyword search, not embeddings (simple and fast, but less semantic).