iflow-mcp-scgreenhalgh-nanokvm-mcp 0.1.0

MCP server for controlling NanoKVM devices

NanoKVM MCP Server

An MCP (Model Context Protocol) server for controlling Sipeed NanoKVM devices. This enables AI assistants like Claude to remotely control hardware via keyboard, mouse, power buttons, and screen capture.

What is NanoKVM?

NanoKVM is an open-source, affordable IP-KVM device based on RISC-V. It allows remote access to computers at the BIOS level—perfect for managing servers, embedded systems, or any headless machine.

What is MCP?

Model Context Protocol is an open standard for connecting AI assistants to external tools and data sources. This server exposes NanoKVM functionality as MCP tools that Claude and other AI assistants can use.

Features

Category	Capabilities
Power Control	Power on/off, reset, force shutdown via ATX header
Keyboard	Type text, send key combinations (Ctrl+C, Alt+F4, etc.)
Mouse/Touch	Click, move, scroll, tap at absolute screen coordinates
Screenshots	Capture display as JPEG from MJPEG video stream
ISO Mounting	Mount/unmount ISO images for remote OS installation
Monitoring	Power LED status, HDD activity, HDMI state, resolution

Installation

From Source

git clone https://github.com/scgreenhalgh/nanokvm-mcp.git
cd nanokvm-mcp
pip install -e .

Dependencies

• Python 3.10+
• mcp - Model Context Protocol SDK
• httpx - Async HTTP client
• websockets - WebSocket client for real-time HID
• pycryptodome - AES encryption for authentication
• pillow - Image processing for screenshots

Configuration

Environment Variables

Variable	Required	Default	Description
NANOKVM_HOST	Yes	-	NanoKVM IP address or hostname
NANOKVM_USER	No	admin	Web UI username
NANOKVM_PASS	No	admin	Web UI password
NANOKVM_SCREEN_WIDTH	No	1920	Target screen width in pixels
NANOKVM_SCREEN_HEIGHT	No	1080	Target screen height in pixels
NANOKVM_HTTPS	No	false	Use HTTPS instead of HTTP

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "nanokvm": {
      "command": "python",
      "args": ["-m", "nanokvm_mcp.server"],
      "env": {
        "NANOKVM_HOST": "192.168.1.100",
        "NANOKVM_USER": "admin",
        "NANOKVM_PASS": "admin",
        "NANOKVM_SCREEN_WIDTH": "1920",
        "NANOKVM_SCREEN_HEIGHT": "1080"
      }
    }
  }
}

Claude Code

Add to your Claude Code MCP configuration:

{
  "mcpServers": {
    "nanokvm": {
      "command": "python",
      "args": ["-m", "nanokvm_mcp.server"],
      "env": {
        "NANOKVM_HOST": "192.168.1.100"
      }
    }
  }
}

Available MCP Tools

Power Control

Tool	Parameters	Description
nanokvm_power	action: power, power_long, reset	Control power button or reset
nanokvm_led_status	-	Get power and HDD LED states

Actions:

• power - Short press (800ms) - normal power on/off
• power_long - Long press (5000ms) - force power off
• reset - Press reset button

Display

Tool	Parameters	Description
nanokvm_hdmi_status	-	Get HDMI connection state and resolution
nanokvm_hdmi_reset	-	Reset HDMI connection
nanokvm_screenshot	-	Capture display as base64 JPEG

Keyboard Input

Tool	Parameters	Description
nanokvm_send_text	text, language	Type text (max 1024 chars)
nanokvm_send_key	key, ctrl, shift, alt, meta	Send single key with modifiers

Supported Keys:

• Letters: a-z
• Numbers: 0-9
• Function keys: f1-f12
• Navigation: up, down, left, right, home, end, pageup, pagedown
• Control: enter, escape, tab, backspace, delete, insert, space

Mouse/Touch Input

Tool	Parameters	Description
nanokvm_tap	x, y	Tap at screen coordinates
nanokvm_click	button, x, y	Click button, optionally at position
nanokvm_move	x, y	Move cursor to position
nanokvm_scroll	amount	Scroll wheel (positive=down)

Coordinate System:

• Origin (0, 0) is top-left corner
• Coordinates are in screen pixels based on SCREEN_WIDTH and SCREEN_HEIGHT
• Internally mapped to NanoKVM's 1-32767 absolute coordinate range

Storage

Tool	Parameters	Description
nanokvm_list_images	-	List available ISO images
nanokvm_mount_iso	file, as_cdrom	Mount ISO image
nanokvm_unmount_iso	-	Unmount current ISO
nanokvm_mounted_image	-	Get mounted image info

System

Tool	Parameters	Description
nanokvm_reset_hid	-	Reset keyboard/mouse devices
nanokvm_info	-	Get NanoKVM device info
nanokvm_hardware	-	Get hardware information

Usage Examples

Once configured, ask Claude to:

Request	Tool Used
"Is the server powered on?"	nanokvm_led_status
"Power on the machine"	nanokvm_power
"Reset the server"	nanokvm_power with action="reset"
"Force shutdown"	nanokvm_power with action="power_long"
"Type 'root' and press enter"	nanokvm_send_text + nanokvm_send_key
"Press Ctrl+Alt+Delete"	nanokvm_send_key with modifiers
"Take a screenshot"	nanokvm_screenshot
"Click at position 500, 300"	nanokvm_click
"Mount the Ubuntu ISO"	nanokvm_mount_iso

Programmatic Usage

You can also use the client library directly:

import asyncio
from nanokvm_mcp import NanoKVMClient

async def main():
    # Initialize client
    client = NanoKVMClient(
        host="192.168.1.100",
        username="admin",
        password="admin",
        screen_width=1920,
        screen_height=1080,
    )

    try:
        # Check power status
        status = await client.get_led_status()
        print(f"Power LED: {status['pwr']}, HDD LED: {status['hdd']}")

        # Get HDMI info
        hdmi = await client.get_hdmi_status()
        print(f"Resolution: {hdmi['width']}x{hdmi['height']}")

        # Type some text
        await client.paste_text("Hello, World!")

        # Send Enter key
        await client.send_key("enter")

        # Take a screenshot
        screenshot = await client.screenshot()
        with open("screenshot.jpg", "wb") as f:
            f.write(screenshot)

        # Click at coordinates
        await client.tap(500, 300)

        # Power cycle
        await client.reset()

    finally:
        await client.close()

asyncio.run(main())

API Reference

See API_REFERENCE.md for complete documentation of the NanoKVM REST API and WebSocket protocol, including:

• Authentication (AES-256-CBC encryption)
• All REST endpoints with request/response formats
• WebSocket HID protocol for keyboard and mouse
• USB HID keycodes reference
• Direct SSH HID access via /dev/hidg*

How It Works

Architecture

┌─────────────────┐     HTTP/WS      ┌─────────────────┐
│   MCP Client    │◄────────────────►│    NanoKVM      │
│  (Claude, etc.) │                  │                 │
└────────┬────────┘                  │  ┌───────────┐  │
         │                           │  │ REST API  │  │
    MCP Protocol                     │  └───────────┘  │
         │                           │  ┌───────────┐  │
┌────────▼────────┐                  │  │ WebSocket │  │
│  nanokvm-mcp    │                  │  │   /api/ws │  │
│     Server      │                  │  └───────────┘  │
│                 │                  │  ┌───────────┐  │
│ • Power control │                  │  │   MJPEG   │  │
│ • HID input     │                  │  │  Stream   │  │
│ • Screenshots   │                  │  └───────────┘  │
└─────────────────┘                  └─────────────────┘

Communication Methods

Feature	Method	Endpoint
Authentication	REST	POST /api/auth/login
Power control	REST	POST /api/vm/gpio
Text input	REST	POST /api/hid/paste
Key/Mouse events	WebSocket	/api/ws
Screenshots	REST	GET /api/stream/mjpeg (parsed)
ISO mounting	REST	POST /api/storage/image/mount

Development

Setup

# Clone repository
git clone https://github.com/scgreenhalgh/nanokvm-mcp.git
cd nanokvm-mcp

# Install with dev dependencies
pip install -e ".[dev]"

# Run tests
pytest

Project Structure

nanokvm-mcp/
├── nanokvm_mcp/
│   ├── __init__.py      # Package exports
│   ├── server.py        # FastMCP server with tool definitions
│   ├── client.py        # NanoKVM API client (REST + WebSocket)
│   ├── auth.py          # AES password encryption
│   └── hid.py           # USB HID keycodes and helpers
├── pyproject.toml       # Package configuration
├── README.md            # This file
└── API_REFERENCE.md     # Complete API documentation

Troubleshooting

Connection Refused

1. Verify NanoKVM is reachable: ping <NANOKVM_HOST>
2. Check web UI is accessible: http://<NANOKVM_HOST>
3. Verify credentials are correct

Authentication Failed

1. Default credentials are admin/admin
2. Check if password was changed in NanoKVM web UI
3. Authentication can be disabled in /etc/kvm/server.yaml

HID Input Not Working

1. Try nanokvm_reset_hid tool
2. Check "Reset HID" in NanoKVM web UI
3. Verify USB cable connection to target machine
4. Check /dev/hidg* devices exist on NanoKVM via SSH

Screenshot Timeout

1. Ensure HDMI is connected and signal detected
2. Check nanokvm_hdmi_status for connection state
3. Try nanokvm_hdmi_reset to reinitialize

License

MIT

Related Projects

• Sipeed NanoKVM - The hardware this server controls
• Model Context Protocol - The protocol specification
• FastMCP - Python MCP framework