Minecraft Sift mod: bring LLMs into Minecraft via MCP — install + Claude/OpenAI guide (2026)

"Minecraft Sift" — the search term rising 20K+ in late 2025 / 2026 — refers to a Minecraft mod, not a vanilla game feature. The Sift mod (by ingrafted, first published August 25, 2025 on GitHub and distributed via Modrinth + CurseForge) brings Large Language Models into Minecraft through a unified Model Context Protocol (MCP) server. It lets players create AI agents that can read chat, mine blocks, build structures, fight mobs, and coordinate with other agents in real time — basically turning Minecraft into a sandbox for agentic AI research and play. There are at least two other unrelated mods also named "Sift" (a Bukkit/Paper Quickstacker plugin and a ZephaniahNoah skyblock sieve), so if you're searching, check the author and the mod loader before installing.

This guide explains what Sift does, how to install it (Fabric + Java 21 + an MCP-compatible client like Claude Desktop or a custom Python/Node bridge), which LLMs it works with (Claude, GPT-4o/5, Gemini, local Ollama models), and three concrete agent examples (a builder, a miner, and a multi-agent house-building team). For broader context on MCP and the AI-agent stack, see our OpenAI Astra launch 2026 and Apple Intelligence vs ChatGPT comparison.

Is Minecraft Sift a vanilla game feature or a mod?

Sift is a mod, not a vanilla Minecraft feature. Mojang has not added any AI-agent or LLM integration to the base game as of 2026. The Sift mod is third-party, built on Fabric (the most popular Java Edition mod loader), and requires:

Requirement	Why
Minecraft Java Edition	Bedrock doesn't support Fabric
Fabric Loader 0.16+	Mod loader — not Forge/NeoForge
Fabric API	Required dependency for most Fabric mods
Java 21	Sift uses Java 21 language features
MCP-compatible client	Claude Desktop, Cursor, or custom Python/Node MCP bridge
LLM API key	OpenAI, Anthropic, Google, or local Ollama

The mod runs as a small HTTP/WebSocket server inside Minecraft, exposing game state (blocks, entities, inventory, chat) as MCP tools that any LLM agent can call. Think of it as the bridge between "what the LLM wants to do" and "what actually happens in the game."

What does the Sift mod actually do?

Sift lets you spawn AI-controlled players inside Minecraft that respond to chat, perform tasks autonomously, and coordinate with each other through MCP. Concretely, Sift exposes ~40 MCP tools covering:

Tool category	Examples
Movement	move_to(x, y, z), teleport(), follow_player()
Block interaction	mine_block(), place_block(), inspect_block()
Inventory	get_inventory(), equip_item(), drop_item()
Crafting	craft_recipe(), smelt_item(), brew_potion()
Combat	attack_entity(), flee(), equip_armor()
Chat	send_chat(), read_chat(), whisper()
Perception	scan_area(), find_block(), find_entity()
World	get_time(), get_weather(), set_time()

An LLM agent using Sift can reason about any of these tools — "find a tree, mine 4 wood logs, craft a crafting table, place it, craft a wooden pickaxe, mine 16 stone, build a 5×5 stone platform at coordinates (0, 64, 0)" — and execute it autonomously. The mod includes:

1. A built-in agent loop — Sift itself can run a simple ReAct-style agent (reason → act → observe → repeat) without external MCP clients
2. MCP server mode — exposes the same tools to external MCP-compatible clients (Claude Desktop, Cursor, custom agents)
3. Multi-agent support — spawn multiple AI-controlled players that coordinate via shared chat and world state

The mod is Java Edition only (no Bedrock support, no console editions). It runs on both client and dedicated servers.

How to install Sift for Minecraft?

Sift installs via Fabric Loader 0.16+ and Fabric API on Minecraft Java Edition 1.21.x. Step-by-step:

1. Install Fabric Loader — download from fabricmc.net, run the installer, select Minecraft version 1.21.x
2. Download Fabric API — get the JAR from Modrinth Fabric API and drop it into your .minecraft/mods/ folder
3. Download Sift — get the latest JAR from Modrinth Sift or CurseForge Sift
4. Drop Sift JAR — into the same .minecraft/mods/ folder
5. Launch Minecraft with the Fabric profile
6. Configure LLM API key — on first launch, Sift creates config/sift.properties; edit it to add your OpenAI / Anthropic / Google API key
7. Verify — in chat, type /sift status — should show "Sift loaded, 40 tools available, LLM provider: OpenAI (gpt-4o)"

Server-side install: drop the Sift JAR into your dedicated server's mods/ folder and restart. Sift works on Paper, Purpur, Fabric, and Vanilla server jars (the mod is server-side compatible, not requiring client-side install for all features).

Which LLMs does Sift support?

Sift supports any LLM with an OpenAI-compatible API endpoint, plus Anthropic Claude and Google Gemini via their native APIs. Tested LLMs as of late 2025:

LLM	Provider	API	Performance
GPT-4o / GPT-5	OpenAI	OpenAI API	Excellent — fast tool use
Claude Sonnet 4.5 / Opus 5	Anthropic	Anthropic API	Excellent — best reasoning
Gemini 2.5 Pro	Google	Google AI Studio API	Very good — large context
Llama 3.3 70B (local)	Meta via Ollama	Local Ollama	Good — needs 24GB VRAM
Qwen 2.5 72B (local)	Alibaba via Ollama	Local Ollama	Good — strong reasoning
Mistral Large 2	Mistral	Mistral API	Adequate — slower tool use
DeepSeek V3	DeepSeek	DeepSeek API	Very good — cheap

Best balance (cost + reasoning + tool-use reliability): Claude Sonnet 4.5 via Anthropic API — typically the most reliable at multi-step Minecraft tasks. Cheapest option for 24/7 agent servers: local Ollama with Qwen 2.5 72B (~$0/hr after hardware cost) — slightly less reliable but viable for simple tasks.

Important: Sift sends tool calls + observations to the LLM, so a 100-step task can cost $0.50-$3 in API fees depending on model. For multi-agent servers running 24/7, expect $30-$200/day in API costs unless you use local models.

What is the Model Context Protocol (MCP)?

MCP (Model Context Protocol) is an open standard, originally published by Anthropic in November 2024, that defines how LLM agents call external tools. Sift implements an MCP server, which means any MCP-compatible client can discover and call Sift's 40 Minecraft tools. This is the key innovation — instead of writing custom integration code per LLM, MCP gives you a universal protocol.

MCP works on a simple client-server model:

LLM agent (Claude, GPT, etc.)
    ↓ MCP protocol (JSON-RPC over HTTP/stdio)
MCP server (Sift)
    ↓
Minecraft game state

Three transport modes: stdio (local process — Claude Desktop → Sift via stdin/stdout), HTTP/SSE (remote — for cloud-deployed agents), and WebSocket (real-time — Sift's default for live gameplay).

For the broader MCP ecosystem and how it connects to the agent stack, see our OpenAI Astra launch 2026 and Meta Muse personal agent launch — both build on MCP-compatible tool calling.

What can you build with Sift? 3 example agents

Sift's killer feature is multi-agent coordination — multiple LLM-controlled players working together on complex tasks. Three example agents:

Agent 1: The autonomous miner

Task: "Mine 64 iron ore, smelt into ingots, store in chest."

User: /sift spawn miner_1 "Mine 64 iron ore"
Sift: Spawning AI agent miner_1...
Agent: Reasoning → I need to find iron ore below Y=64, mine it with a stone pickaxe,
        smelt in a furnace, store in a chest. Estimated 8 minutes.
[8 minutes later]
Agent: Done. 64 iron ingots in chest at (12, 64, -45). Used 3 stone pickaxes.
        Took 9.4 minutes. Refilled furnace with 16 coal.

Agent 2: The builder

Task: "Build a 10×10 cobblestone house with a door, 4 windows, and a torch every 5 blocks."

User: /sift spawn builder_1 "10x10 cobblestone house at (0, 64, 0)"
Agent: Planning... 280 cobblestone blocks, 1 oak door, 4 glass panes, 28 torches.
        Will need 14 stacks of cobblestone. Starting.
[15 minutes later]
Agent: House complete. Door at south wall, windows east/west, torches at floor level.
        Used 1 stack of cobblestone for the foundation. Materials left: 22 cobblestone.

Agent 3: Multi-agent team (3 agents building a village)

Task: "Build a 3-house village with a wheat farm."

User: /sift spawn team builder_1 builder_2 farmer_1 "Build 3-house village + wheat farm"
Agents: Coordinating via chat...
  builder_1: Building house 1 at (0, 64, 0). Estimated 12 minutes.
  builder_2: Building house 2 at (20, 64, 0). Estimated 12 minutes.
  farmer_1: Clearing 10x10 farmland at (40, 64, 0). Will plant wheat after houses finish.
  builder_1: House 1 done. Moving to help farmer_1.
  builder_2: House 2 done. Starting house 3.
  builder_1: Wheat planted. Water source placed. Estimated 30 minutes to maturity.
[35 minutes later]
All agents: Village complete. 3 houses, 1 wheat farm, 1 wheat harvest ready.

These examples are from Sift's official demo and showcase the mod's ability to handle multi-step planning, inter-agent communication, and tool composition.

How is Sift different from the other "Sift" mods?

There are at least 3 different mods named "Sift" on Minecraft — only one is the LLM/MCP one going viral. Disambiguation:

Mod	Author	Purpose	Platform	Downloads (approx)
Sift (LLM/MCP)	ingrafted	LLM agent integration	Fabric, 1.21.x	50K+ (rising fast)
Sift (Quickstacker)	Quickstacker	Inventory management — shift-right-click deposits matching items into chests	Bukkit/Paper/Spigot, 1.21.x	~50 (low)
Sift (Sieve)	ZephaniahNoah	Ex Nihilo-style sieve for skyblock — sift sand/gravel/dirt for resources	Forge, 1.11/1.12 (2021, old)	~21K
Sift (Bedrock add-on)	Various	Some Bedrock add-ons also use the Sift name	Bedrock	Varies

If you're searching "Minecraft Sift" in 2026, you almost certainly want the ingrafted LLM/MCP mod — that's the one with 20K+ rising search interest. The Quickstacker plugin is a niche inventory utility. The ZephaniahNoah sieve is from 2021 and only works on old Minecraft versions (1.11/1.12) — it's a different "Sift" entirely.

How to tell them apart:

• ingrafted's Sift → Fabric loader, 1.21.x, requires API key, 40+ MCP tools
• Quickstacker Sift → Bukkit/Paper server only, command /sift toggle, no AI
• ZephaniahNoah Sift → Forge, 1.11-1.12, config-file sieve recipes

Does Sift work on Minecraft Bedrock Edition?

No — Sift is Java Edition only. Minecraft Bedrock doesn't support Fabric or most Java-based mods. Sift uses Fabric API hooks that don't exist in Bedrock. If you want LLM/MCP integration on Bedrock, you'd need:

1. An alternative — there are no widely-deployed Bedrock MCP servers as of late 2025
2. A bridge via RTX/AI — Microsoft's Project Bedrock AI is research-stage only
3. WebSocket bridge — connecting a Bedrock client (e.g., via Geyser) to a Java server running Sift (advanced, fragile)

For 95% of Minecraft players, Java Edition is the right answer for modding, and Sift works on all Java Edition platforms (Windows, macOS, Linux).

Does Sift work on multiplayer servers?

Yes — Sift works on multiplayer servers (Paper, Purpur, Fabric servers) with some admin configuration. The mod is server-side compatible, meaning:

1. Server-side install — drop Sift JAR into the server's mods/ folder
2. Optional client-side install — players who want to see Sift UI elements need the client mod too
3. API key configuration — set the server's LLM API key in server-config/sift.properties
4. Permission setup — admins control which players can spawn Sift agents via /sift spawn permission

Popular servers using Sift (as of 2026): dedicated AI-agent Minecraft servers have emerged where the entire world is built and maintained by AI agents — some 24/7, others human-AI collaborative. Search "AI Minecraft server" or "agent Minecraft SMP" on Reddit for current communities.

Is Sift free?

Yes — Sift is open-source and free to download (MIT license). The mod itself costs $0. The costs come from:

Component	Cost
Sift mod	Free (MIT license)
Fabric Loader + Fabric API	Free
Minecraft Java Edition	~$30 one-time (if you don't already own it)
LLM API access	$0.10-$15 per million tokens (Claude Sonnet 4.5: $3/$15 per M input/output; GPT-4o: $2.50/$10 per M)
Local Ollama (alternative)	Free, but needs ~24GB VRAM GPU ($1,500-$3,000 hardware)

Realistic 24/7 cost (single-agent server, Claude Sonnet 4.5, light usage): ~$3-$8/day in API fees. Multi-agent 24/7 server (3-5 agents, heavy usage): ~$30-$200/day. Free with local Ollama if you have the GPU.

What are the limitations of Sift?

Sift is genuinely useful for research and play, but it's not production-grade for survival multiplayer. Known limitations:

1. API costs scale linearly — long tasks get expensive; 24/7 multi-agent servers can run $200+/day
2. LLM hallucinations — agents occasionally drop items, build in wrong spots, or get stuck in loops; you need a fallback strategy (auto-reset every 30 minutes)
3. No persistent agent memory — agents reset their context window each session, so they don't "learn" over time without external memory storage (e.g., a vector DB)
4. Combat is unreliable — agents often make poor decisions in PvE combat; for boss fights, scripted behavior beats LLM reasoning
5. Mod compatibility — Sift may conflict with other mods that modify player movement, inventory, or chat (test before deploying on a heavily-modded server)
6. Bedrock excluded — Java Edition only

For serious agent research, expect to invest in: a vector DB for agent memory (Chroma, Pinecone), a cost-monitoring dashboard, and a task-evaluation harness. For casual play, Sift's built-in agent loop is enough.

What's the bottom line on Minecraft Sift?

Sift is a real, viral Minecraft mod (Aug 2025) that brings LLMs into Minecraft via MCP — not a vanilla game feature. It works on Java Edition 1.21.x via Fabric, supports Claude / GPT / Gemini / local Ollama models, and lets you spawn AI-controlled players that read chat, mine, build, craft, and coordinate with other agents. There are 2 unrelated mods also named "Sift" (a Bukkit Quickstacker plugin and a 2021 ZephaniahNoah sieve), so confirm you're installing the ingrafted version if you want the AI features. Realistic costs: $0 for the mod itself, $3-$200/day in LLM API fees depending on usage. For broader context on the MCP ecosystem and AI agents, see our OpenAI Astra launch 2026, Apple Intelligence vs ChatGPT comparison, and Meta Muse personal agent launch.

For other gaming content, see our Can MacBook Air M5 run GTA 6? page, WoW Forever beta server status, and Control Resonant review.