dcc-mcp-substance3d-designer

Substance 3D Designer adapter for the DCC Model Context Protocol (MCP).

The package runs an embedded Streamable HTTP MCP server inside Designer, so tools execute through Designer's Qt main thread instead of a separate process.

Install and load

Install this package with the Python environment used by Substance 3D Designer:

python -m pip install dcc-mcp-substance3d-designer

For unattended startup, append the installed package's dcc_mcp_substance3d_designer/designer/plugins directory to SBS_DESIGNER_PYTHON_PATH. Designer discovers the dedicated dcc_mcp_substance3d_designer_plugin module without scanning the adapter's implementation modules as plugins.

For an interactive installation, open Tools > Plugin Manager, browse to dcc_mcp_substance3d_designer/designer_plugin.py, then load the plugin. The MCP endpoint defaults to http://127.0.0.1:8765/mcp.

Set DCC_MCP_SUBSTANCE3D_DESIGNER_PORT before launching Designer to choose a different port. Standard DCC_MCP_GATEWAY_PORT and DCC_MCP_REGISTRY_DIR settings are also honoured.

For unattended launches, pass Designer a persistent configuration with --config-file <path-to-default_configuration.sbscfg>. This prevents a stale session-specific configuration reference from opening a blocking startup dialog.

Related MCP server: MCP Affinity Designer Server

Bundled skills

designer-session provides typed tools for inspecting the active Designer session and creating a rendered procedural PBR material package. Host APIs are imported only while a tool runs, so metadata discovery remains safe outside Designer.

Development

python -m pip install -e ".[dev]"
python -m pytest
ruff check src tests tools
python -m build

Releases use release-please. The release.yml workflow publishes through the pypi environment using PyPI Trusted Publishing.