houdini-mcp-server

# 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 ```bash cd ~/Library/Preferences/houdini/20.5/ # macOS git clone https://github.com/YOUR_USERNAME/houdini-mcp-server ``` ### 2. Create Python venv and install dependencies ```bash 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) ```python 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: ```json { "$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](https://opencode.ai/docs/mcp-servers/). **Claude Desktop** (`~/.config/claude/claude_desktop_config.json`): ```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