👾🦀 MiSTerClaw — MCP Remote Control for MiSTer-FPGA

MiSTerClaw is the first MCP server for MiSTer-FPGA. Control your MiSTer from any AI agent.

What is this?

MiSTerClaw lets AI agents — Claude, ChatGPT, OpenClaw, Hermes, Cursor, and others — control a MiSTer-FPGA over the network. Launch games, search your ROM library, take screenshots, read and modify core settings and DIP switches, navigate the OSD menu, manage the system, and even set up Tailscale VPN for secure remote access from anywhere. It uses the Model Context Protocol (MCP) standard, so any MCP-compatible client works out of the box. For agents without MCP support, a CLI client is also included.

MCP Setup

Add MiSTerClaw to your MCP client config:

Claude Desktop (claude_desktop_config.json):

{
  "mcpServers": {
    "misterclaw": {
      "command": "/path/to/misterclaw-mcp",
      "args": ["--host", "mister-fpga"]
    }
  }
}

Cursor (.cursor/mcp.json):

{
  "mcpServers": {
    "misterclaw": {
      "command": "/path/to/misterclaw-mcp",
      "args": ["--host", "mister-fpga"]
    }
  }
}

MCP Tools

Tool	Description
`mister_status`	What's currently playing
`mister_launch`	Launch a game by search or path
`mister_search`	Search the ROM library
`mister_systems`	List all available systems with ROM counts
`mister_screenshot`	Take a screenshot (returns PNG image)
`mister_info`	System info (hostname, IP, temp, RAM, disks, uptime)
`mister_input`	Send keyboard input (OSD navigation, named keys)
`mister_osd_info`	Query OSD menu structure from CONF_STR database
`mister_osd_visible`	Show only visible OSD menu items based on current config
`mister_cfg_read`	Read core settings (options + DIP switches)
`mister_cfg_write`	Modify core settings with automatic backup
`mister_reload`	Reload current core to apply config changes
`mister_rescan`	Rescan ROM library (optionally for specific drive)
`mister_tailscale`	Manage Tailscale VPN
`mister_shell`	Execute shell commands

Example Conversations

Once configured, just talk to your agent:

You: "What games do I have for SNES?"
Agent: You have 13,435 SNES ROMs! Here are some highlights...

You: "Launch Street Fighter 2"
Agent: 🎮 Launched Street Fighter II Turbo on SNES!

You: "Take a screenshot and show me"
Agent: [screenshot of the game running]

You: "What systems do I have?"
Agent: Your MiSTer has 70+ systems! Top ones:
  - SNES: 13,435 ROMs
  - C64: 46,736 ROMs
  - Amiga: 55,793 ROMs
  ...

You: "Set up Tailscale so I can reach the MiSTer from anywhere"
Agent: Installing Tailscale... Done!
       Please authenticate: https://login.tailscale.com/a/xxx
       After that your MiSTer is reachable from anywhere.

You: "What settings does R-Type have?"
Agent: R-Type (M72 core) has these settings:
       Core Options:
         - No Death Mode: Off
         - Service Mode: Off
       DIP Switches:
         - Difficulty: Medium
         - Coin A: 1 Coin / 1 Credit
         - Lives: 3
         - Demo Sounds: On
         - Continue: Yes

You: "Enable No Death Mode"
Agent: ⚙️ Set "No Death Mode" to On in R-Type.
       The core reloads automatically — change is live!

CLI Client

For agents that have shell access (like OpenClaw, Codex, or Claude Code), the CLI client can be more efficient than MCP — no tool schemas in context, just call it when needed. It's also useful for shell scripts and automation.

# Check what's playing
misterclaw-send -H mister-fpga status

# Search for games
misterclaw-send -H mister-fpga search "zelda" --limit 5
misterclaw-send -H mister-fpga search "sonic" --system MegaDrive

# Launch a game
misterclaw-send -H mister-fpga launch "super mario world" --system SNES

# List all systems with ROM counts
misterclaw-send -H mister-fpga systems

# Take a screenshot
misterclaw-send -H mister-fpga screenshot -o game.png

# System info (CPU, memory, storage, uptime)
misterclaw-send -H mister-fpga info

# Run shell commands — configure MiSTer.ini, run updates, manage files
misterclaw-send -H mister-fpga shell "cat /media/fat/MiSTer.ini"
misterclaw-send -H mister-fpga shell "/media/fat/Scripts/update_all.sh"

# Send keyboard input (OSD navigation)
misterclaw-send -H mister-fpga input key osd
misterclaw-send -H mister-fpga input combo leftalt f12

# Query OSD menu structure
misterclaw-send -H mister-fpga osd-info
misterclaw-send -H mister-fpga osd-info --core SNES

# Read core settings (options + DIP switches)
misterclaw-send -H mister-fpga cfg-read

# Modify settings
misterclaw-send -H mister-fpga cfg-write --option "Free Play" --value On

# Reload core to apply changes
misterclaw-send -H mister-fpga reload

# Rescan ROM library (after adding new games)
misterclaw-send -H mister-fpga rescan
misterclaw-send -H mister-fpga rescan --location usb0

# JSON output for scripting
misterclaw-send -H mister-fpga status --json
misterclaw-send -H mister-fpga systems --json

All commands support --json for machine-readable output.

Installation

Three binaries:

Binary	Runs on	Purpose
`misterclaw`	MiSTer (ARM7)	Server — runs on the MiSTer itself
`misterclaw-send`	Anywhere	CLI client for direct commands
`misterclaw-mcp`	Your machine	MCP server — bridges AI agents to MiSTer

Quick install on MiSTer

scp misterclaw root@<mister-ip>:/media/fat/Scripts/
ssh root@<mister-ip> "/media/fat/Scripts/misterclaw --install"

Or self-install: copy the binary to MiSTer, then run misterclaw --install. This copies to /media/fat/Scripts/, configures autostart on boot, and is idempotent.

To uninstall: /media/fat/Scripts/misterclaw --uninstall

Security

⚠️ Do not expose port 9900 to the internet. The ClawExec protocol has no authentication or encryption.

Tailscale VPN (recommended) — encrypted, authenticated, works from anywhere
Local network only — keep port 9900 accessible within your LAN
Never forward port 9900 through your router or firewall

Architecture

Agent ←MCP→ misterclaw-mcp ←TCP→ MiSTer:9900 (misterclaw server)
Agent ←CLI→ misterclaw-send ←TCP→ MiSTer:9900 (misterclaw server)

The MCP server and CLI client communicate with the MiSTer over the ClawExec protocol (newline-delimited JSON over TCP, port 9900).

Dynamic System Detection

MiSTerClaw auto-detects all systems by scanning ROM folders, installed cores, and MGL files. No configuration needed — a well-stocked MiSTer typically has 70+ systems. Discovery results (including full ROM file listings) are cached to disk. First startup scans and builds the cache; subsequent starts load instantly. Use the rescan command after adding new games or drives.

Building from Source

# MiSTer server (ARM7)
GOOS=linux GOARCH=arm GOARM=7 go build -ldflags="-s -w" -o misterclaw ./cmd/misterclaw/

# CLI client
go build -ldflags="-s -w" -o misterclaw-send ./cmd/misterclaw-send/

# MCP server
go build -ldflags="-s -w" -o misterclaw-mcp ./cmd/misterclaw-mcp/

License

MIT

MiSTerClaw