Houdini MCP Server

Control Houdini from AI assistants via the Model Context Protocol (MCP).

What It Does

Allows MCP-compatible AI tools (like OpenCode, Claude Desktop, etc.) to:

• Execute Python code in Houdini with full hou module access
• Query scene information (nodes, frames, selection, etc.)
• Create and manipulate nodes programmatically

Install

1. Clone this repo

cd ~/Library/Preferences/houdini/20.5/  # macOS
git clone https://github.com/YOUR_USERNAME/houdini-mcp-server

2. Create Python venv and install dependencies

cd houdini-mcp-server
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
deactivate

3. Install shelf tools (one-liner in Houdini Python Shell)

exec(open('/Users/YOUR_USERNAME/Library/Preferences/houdini/20.5/houdini-mcp-server/install_mcp_shelf.py').read())

4. Configure your AI client

OpenCode - Edit ~/.config/opencode/opencode.json and add to the mcp section:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "houdini": {
      "type": "local",
      "command": [
        "/Users/YOUR_USERNAME/Library/Preferences/houdini/20.5/houdini-mcp-server/venv/bin/python",
        "/Users/YOUR_USERNAME/Library/Preferences/houdini/20.5/houdini-mcp-server/python/houdini_mcp_server.py"
      ],
      "enabled": true
    }
  }
}

More info at official opencode docs.

Claude Desktop (~/.config/claude/claude_desktop_config.json):

{
  "mcpServers": {
    "houdini": {
      "command": "/Users/YOUR_USERNAME/Library/Preferences/houdini/20.5/houdini-mcp-server/venv/bin/python",
      "args": [
        "/Users/YOUR_USERNAME/Library/Preferences/houdini/20.5/houdini-mcp-server/python/houdini_mcp_server.py"
      ]
    }
  }
}

Usage

1. Start Houdini and click the "Start MCP" shelf button
2. Start your AI client (OpenCode, Claude Desktop, etc.) and make sure that Houdini MCP is enabled (in opencode /mcps)
3. Make a prompt with Houdini in mind to control Houdini

Examples

Randomize poins

For each scattered point randomize its size, rotation on Y and color.

This will most likely create a wrangler node with necessary expressions.

Making special effects

On currently selected point wrangler write vex that will display geometry by a wave that pass trough it as I scrub the timeline. Allow for editing wave amplitude, frequency, timing etc.

Available Tools

• execute_python - Run arbitrary Python code with hou module access
• get_scene_info - Get hip file path, frame range, selected nodes, FPS, etc.

Requirements

• Houdini 20.5+ (tested on macOS)
• Python 3.11+
• MCP-compatible AI client

Architecture

AI Client ←→ MCP Server ←→ HTTP ←→ RPC Service ←→ Houdini
         stdio      (venv)    :9876   (inside Houdini)

• houdini_mcp_server.py - Runs outside Houdini in venv, handles MCP protocol
• houdini_rpc_service.py - Runs inside Houdini, executes code with hou module access

Uses HTTP bridge because Houdini's asyncio implementation is incompatible with MCP SDK.

License

MIT