dcc-mcp-houdini

SideFX Houdini adapter for the DCC Model Context Protocol (MCP) ecosystem. It embeds a Streamable HTTP MCP server inside Houdini/hython and exposes skills-first Houdini automation tools to agents.

Features

• Embedded MCP Streamable HTTP server inside Houdini
• Auto-gateway with first-wins port competition (port 8765)
• Progressive skill loading (discover → load → unload)
• Houdini Python (hython) and interactive UI-thread dispatch
• Python 3.7+ package metadata for older Houdini runtimes
• Bundled skills for scripting, scene inspection, node authoring, HDA execution, and automation
• Wheel, sdist, and Houdini quickinstall ZIP release assets
• Prometheus metrics endpoint (/metrics), job persistence, and workflow engine support
• Optional licensed Houdini Docker E2E workflow

Installation

Release Wheel

pip install dcc-mcp-houdini

For an unreleased GitHub asset, install a release wheel directly:

pip install https://github.com/loonghao/dcc-mcp-houdini/releases/download/v0.1.0/dcc_mcp_houdini-0.1.0-py3-none-any.whl

Houdini Quickinstall ZIP

Download dcc_mcp_houdini_quickinstall_<platform>_v<version>.zip from GitHub Releases, extract it to a stable folder, then run:

powershell -ExecutionPolicy Bypass -File install.ps1 -HoudiniVersion 20.5

On Linux/macOS:

chmod +x install.sh
./install.sh 20.5

The package writes a Houdini package JSON into the user preferences folder. On startup, scripts/123.py extracts bundled wheels into vendor/ and starts the MCP server unless DCC_MCP_HOUDINI_AUTOSTART=0.

Usage

import dcc_mcp_houdini

server = dcc_mcp_houdini.start_server()
print(server.mcp_url)  # http://127.0.0.1:8765/mcp

Default minimal mode (DCC_MCP_MINIMAL=1) loads only:

• houdini-scripting
• houdini-scene

Use progressive discovery for heavier tools:

search_skills(query="hda")
load_skill("houdini-hda")
call houdini_hda__execute_hda

Local MCP debug (Cursor / Claude)

See docs/guide/local-mcp-debug.md and copy examples/mcp/cursor-houdini-streamable-http.json into your MCP host config.

Development

# Install dependencies
just dev

# Run tests
just test

# Lint
just lint-all

# Windows: build dcc-mcp-core with Houdini's Python and symlink
just houdini-version=20.5 houdini-dev-build-link-core-win

# Windows: start Houdini with debugpy
just houdini-version=20.5 houdini-dev-debug-win

# Build wheel + platform quickinstall package
just build-houdini-package platform=win64

Release Publishing

The Release workflow publishes to PyPI when release-please creates a new release. To backfill an existing GitHub release tag, run the Release workflow manually with tag_name=vX.Y.Z and publish_to_pypi=true. Publishing uses PyPI trusted publishing when configured, or PYPI_API_TOKEN when that secret is available.

Bundled Skills

| Skill | Stage | Tools | |-------|-------|-------| | houdini-scripting | bootstrap | execute_python, get_session_info | | houdini-scene | scene | get_scene_info, list_obj_nodes, list_child_nodes, get_node_info | | houdini-nodes | authoring | create_node, set_node_parms, connect_nodes, cook_node, layout_children, delete_node | | houdini-materials | authoring | create_material, assign_material | | houdini-hda | authoring | install_hda_file, list_hda_definitions, execute_hda, save_node_as_hda | | houdini-automation | pipeline | run_python_file, set_frame_range, save_hip_file, load_hip_file, build_node_chain |

CI and Houdini Docker

Normal CI runs without Houdini installed: unit tests, skill validation, Python 3.7 syntax checks, wheel/sdist build, and quickinstall ZIP assembly.

Live Houdini E2E is in .github/workflows/e2e.yml. It defaults to sabjorn/hbuild-worker:21.0.559-base and runs only when SideFX licensing secrets are configured. See docs/ci/houdini-docker.md.

Project Structure

dcc-mcp-houdini/
├── src/dcc_mcp_houdini/        # Python package and bundled skills
├── packaging/                  # Quickinstall ZIP assembly
├── tests/                      # Unit and packaging tests
├── tools/                      # Dev, lint, and syntax scripts
├── examples/                   # Usage examples
├── docs/                       # Guides and CI notes
├── justfile                    # Task runner
└── pyproject.toml              # Build config

Requirements

• Houdini with Python 3.7+ (hython or interactive Houdini)
• dcc-mcp-core >= 0.17.26
• See pyproject.toml for full dependencies

License

MIT