houdini-mcp-server

Houdini MCP

Connect SideFX Houdini to Claude, Codex, Gemini, Cursor, opencode or pi.

This MCP provides Full Markdown Documentation and Viewport Screenshots support to your agents of choice, enabling strong feedback loops and autonomous workflows.

Install

Windows

powershell -c "irm https://raw.githubusercontent.com/JTCHE/houdini-mcp/main/bootstrap.bat -OutFile bootstrap.bat; .\bootstrap.bat"

macOS / Linux

curl -sSL https://raw.githubusercontent.com/JTCHE/houdini-mcp/main/bootstrap.sh | bash

uv

uv tool install houdini-mcp-server && houdinimcp-install

The installer adds the plugin to Houdini and the server to your AI clients of choice. Restart both.
pi also needs pi install npm:pi-mcp-adapter.

Claude plugin

This repository is also a Claude plugin, for Claude Code and for Cowork on your computer. It needs uv. The plugin starts a headless Houdini without setup. To connect the Houdini that you have open, ask Claude to run the houdini-setup skill.

What the plugin runs

• uv run --frozen builds an environment from uv.lock in the plugin folder, then starts the MCP server from this repository.
• The server talks to Houdini on localhost only. It starts hython, or houdini on request, from your Houdini install, and ffmpeg to encode a flipbook movie.
• docs reads the documentation out of your Houdini install with houdinimd-docs. It sends nothing over the network.
• houdini-setup writes the HoudiniMCP package into your Houdini preferences folder, after you approve it.
• No tool sends data to a remote service. execute runs any Python that Claude writes in your Houdini session.

Tools

Read	scene_overview node_inspect geometry_inspect stage_inspect select console
Edit	node_edit parm_set connect hda batch
Run	cook render pdg playbar scene_file
See	capture: the viewport, a camera, four views or a flipbook
Code	execute: Python, HScript, expressions, VEX check
Docs	docs: the Houdini documentation of your build, offline, from houdinimd-docs
Session	session: status; starts Houdini headless or with its window

No Houdini open? The server starts a headless hython.

batch builds a whole network in one call, and it is all or nothing: a failed step undoes the steps before it. A build that works comes back with the cooked point and primitive counts, and the nodes with errors.

Warning: execute runs any Python in Houdini. Save your work.

Troubleshooting

Problem	Fix
No Houdini listens for the bridge	Start Houdini, or click Toggle MCP Server on the HoudiniMCP shelf.
No HoudiniMCP shelf	Restart Houdini. houdinimcp-install --list shows where the plugin went.
Houdini started from Git Bash has no plugin	Git Bash sets HOME. Set the user variable HOUDINI_USER_PREF_DIR to %USERPROFILE%\Documents\houdini__HVER__.
capture says there is no viewport	The session is headless. Call session with action="start_gui".
You must have a fixed port	Set HOUDINIMCP_PORT for Houdini and for the bridge. Without it, the plugin takes a free port from the operating system and tells the bridge which one.

For agents and scripts

Without a terminal, the installer asks nothing and takes the defaults.

houdinimcp-install --list          # Houdini installs and clients found, as JSON
houdinimcp-install --yes --json    # newest Houdini, every client found; JSON report
houdinimcp-install --houdini-version 22.0 --harness claude-code --yes
houdinimcp-install --dry-run --yes # change nothing
houdinimcp-install --uninstall     # remove the plugin and every client entry

Flags: --houdini-version none skips the plugin, --prefs-dir PATH names the prefs folder, --harness none|all|KEY (repeatable), --quiet-start stops the first-launch dialogs. The bootstrap scripts pass every flag through.

Manual client setup: run houdinimcp-bridge with no arguments. claude mcp add --transport stdio houdini -- houdinimcp-bridge for Claude Code.

From a clone: uv run python -m bridge.onboarding.install.

Layout: src/houdinimcp/ is the plugin, a TCP server inside Houdini on localhost:9877. src/bridge/ is the MCP server and the installer. Messages are JSON with a 4-byte length prefix. HOUDINIMCP_NO_HEADLESS=1 stops the headless start. Read AGENTS.md before you change code.

Credits

Built on blender-mcp, capoomgit/houdini-mcp, eetumartola/houdini-mcp, Houdini21MCP and fxhoudinimcp. MIT licensed.

_{Not affiliated with SideFX. Houdini and SideFX are trademarks of SideFX Software Inc.}