Unsloth MCP Server

An MCP server for Unsloth - a library that makes LLM fine-tuning 2x faster with 80% less memory.

What is Unsloth?

Unsloth is a library that dramatically improves the efficiency of fine-tuning large language models:

• Speed: 2x faster fine-tuning compared to standard methods
• Memory: 80% less VRAM usage, allowing fine-tuning of larger models on consumer GPUs
• Context Length: Up to 13x longer context lengths (e.g., 89K tokens for Llama 3.3 on 80GB GPUs)
• Accuracy: No loss in model quality or performance

Unsloth achieves these improvements through custom CUDA kernels written in OpenAI's Triton language, optimized backpropagation, and dynamic 4-bit quantization.

Features

• Optimize fine-tuning for Llama, Mistral, Phi, Gemma, and other models
• 4-bit quantization for efficient training
• Extended context length support
• Simple API for model loading, fine-tuning, and inference
• Export to various formats (GGUF, Hugging Face, etc.)

Installation

Current state: install from source (below). The package is prepared for npm (name, bin, server.json registry manifest are in place) but is not yet published — the npx-based config in the next section works only after the npm publish lands.

1. Install Unsloth on the machine that will run the fine-tuning: pip install unsloth

2. Build the server from source:

   git clone https://github.com/OtotaO/unsloth-mcp-server.git
   cd unsloth-mcp-server
   npm install
   npm run build
   

3. Point your MCP client (Claude Desktop, Claude Code, Cline, Cursor, …) at the built entrypoint:

   {
     "mcpServers": {
       "unsloth": {
         "command": "node",
         "args": ["/path/to/unsloth-mcp-server/build/index.js"],
         "env": { "HUGGINGFACE_TOKEN": "your_token_here" }
       }
     }
   }
   

   HUGGINGFACE_TOKEN is optional (only needed for gated/private models). Omit the env block if you don't use one.

After npm publish (planned)

Once published to npm as unsloth-mcp-server, the same clients can run it over stdio via npx with no clone/build:

{
  "mcpServers": {
    "unsloth": {
      "command": "npx",
      "args": ["-y", "unsloth-mcp-server"],
      "env": { "HUGGINGFACE_TOKEN": "your_token_here" }
    }
  }
}

For Claude Code: claude mcp add unsloth -- npx -y unsloth-mcp-server

Available Tools

check_installation

Verify if Unsloth is properly installed on your system.

Parameters: None

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "check_installation",
  arguments: {}
});

list_supported_models

Get a list of all models supported by Unsloth, including Llama, Mistral, Phi, and Gemma variants.

Parameters: None

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "list_supported_models",
  arguments: {}
});

load_model

Load a pretrained model with Unsloth optimizations for faster inference and fine-tuning.

Parameters:

• model_name (required): Name of the model to load (e.g., "unsloth/Llama-3.2-1B")
• max_seq_length (optional): Maximum sequence length for the model (default: 2048)
• load_in_4bit (optional): Whether to load the model in 4-bit quantization (default: true)
• use_gradient_checkpointing (optional): Whether to use gradient checkpointing to save memory (default: true)

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "load_model",
  arguments: {
    model_name: "unsloth/Llama-3.2-1B",
    max_seq_length: 4096,
    load_in_4bit: true
  }
});

finetune_model

Fine-tune a model with Unsloth optimizations using LoRA/QLoRA techniques.

Parameters:

• model_name (required): Name of the model to fine-tune
• dataset_name (required): Name of the dataset to use for fine-tuning
• output_dir (required): Directory to save the fine-tuned model
• max_seq_length (optional): Maximum sequence length for training (default: 2048)
• lora_rank (optional): Rank for LoRA fine-tuning (default: 16)
• lora_alpha (optional): Alpha for LoRA fine-tuning (default: 16)
• batch_size (optional): Batch size for training (default: 2)
• gradient_accumulation_steps (optional): Number of gradient accumulation steps (default: 4)
• learning_rate (optional): Learning rate for training (default: 2e-4)
• max_steps (optional): Maximum number of training steps (default: 100)
• dataset_text_field (optional): Field in the dataset containing the text (default: 'text')
• load_in_4bit (optional): Whether to use 4-bit quantization (default: true)

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "finetune_model",
  arguments: {
    model_name: "unsloth/Llama-3.2-1B",
    dataset_name: "tatsu-lab/alpaca",
    output_dir: "./fine-tuned-model",
    max_steps: 100,
    batch_size: 2,
    learning_rate: 2e-4
  }
});

generate_text

Generate text using a fine-tuned Unsloth model.

Parameters:

• model_path (required): Path to the fine-tuned model
• prompt (required): Prompt for text generation
• max_new_tokens (optional): Maximum number of tokens to generate (default: 256)
• temperature (optional): Temperature for text generation (default: 0.7)
• top_p (optional): Top-p for text generation (default: 0.9)

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "generate_text",
  arguments: {
    model_path: "./fine-tuned-model",
    prompt: "Write a short story about a robot learning to paint:",
    max_new_tokens: 512,
    temperature: 0.8
  }
});

export_model

Export a fine-tuned Unsloth model to various formats for deployment.

Parameters:

• model_path (required): Path to the fine-tuned model
• export_format (required): Format to export to (gguf, ollama, vllm, huggingface)
• output_path (required): Path to save the exported model
• quantization_bits (optional): Bits for quantization (for GGUF export) (default: 4)

Example:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "export_model",
  arguments: {
    model_path: "./fine-tuned-model",
    export_format: "gguf",
    output_path: "./exported-model.gguf",
    quantization_bits: 4
  }
});

Advanced Usage

Custom Datasets

You can use custom datasets by formatting them properly and hosting them on Hugging Face or providing a local path:

const result = await use_mcp_tool({
  server_name: "unsloth",
  tool_name: "finetune_model",
  arguments: {
    model_name: "unsloth/Llama-3.2-1B",
    dataset_name: "json",
    data_files: {"train": "path/to/your/data.json"},
    output_dir: "./fine-tuned-model"
  }
});

Memory Optimization

For large models on limited hardware:

• Reduce batch size and increase gradient accumulation steps
• Use 4-bit quantization
• Enable gradient checkpointing
• Reduce sequence length if possible

Troubleshooting

Common Issues

1. CUDA Out of Memory: Reduce batch size, use 4-bit quantization, or try a smaller model
2. Import Errors: Ensure you have the correct versions of torch, transformers, and unsloth installed
3. Model Not Found: Check that you're using a supported model name or have access to private models

Version Compatibility

• Python: 3.10, 3.11, or 3.12 (not 3.13)
• CUDA: 11.8 or 12.1+ recommended
• PyTorch: 2.0+ recommended

Performance Benchmarks

Requirements

• Python 3.10-3.12
• NVIDIA GPU with CUDA support (recommended)
• Node.js and npm

License

Apache-2.0