Blender MCP Router

FastMCP server that exposes two layers of functionality:

• LLM routing through LiteLLM so a single FastMCP tool can reach OpenAI, Anthropic, xAI, or any other LiteLLM-supported provider.
• Blender bridge that proxies to the Blender MCP add-on over a persistent TCP socket, providing scene inspection, PolyHaven / Sketchfab helpers, and Hyper3D automation.

The server is designed for FastMCP Hub distribution: pyproject.toml defines the package, the MCP endpoint is hosted via FastMCP, and an optional REST shim is exposed for the Blender add-on.

Requirements

• Python 3.10+
• Blender MCP add-on running locally (for the Blender tools)
• API keys for any LLM providers you plan to route through LiteLLM

Install dependencies via:

pip install -e .

Configuration

Copy .env.example to .env and fill in the values.

Variable	Purpose
OPENAI_API_KEY	Used by LiteLLM when routing to OpenAI models
XAI_API_KEY	Used for xAI (Grok) requests via LiteLLM
ANTHROPIC_API_KEY	Used for Anthropics models via LiteLLM
OPENAI_MODEL	Optional override for the gpt-5 alias
XAI_MODEL	Optional override for the grok-4-fast alias
ANTHROPIC_MODEL	Optional override for the claude-4 alias
MCP_REST_TOKEN	Shared secret for REST shim (X-Token header)

All LLM-specific environment variables supported by LiteLLM can be passed through here as well (see LiteLLM docs for provider-specific keys).

Running

After configuration, start the server via the script entry point:

blender-mcp-router

The process starts two services:

• FastMCP HTTP endpoint on 127.0.0.1:8974/mcp
• REST bridge for the Blender add-on on 127.0.0.1:8975

Both services are started inside server.main() so FastMCP Hub (or pipx run blender-mcp-router) can launch them.

MCP Tools

server.py registers the following FastMCP tools:

• generate_text: Unified text generation routed through LiteLLM
• Blender tools: get_scene_info, get_object_info, get_viewport_screenshot, execute_blender_code, PolyHaven/Sketchfab helpers, and Hyper3D automation helpers

Each Blender tool forwards to the Blender MCP add-on using a JSON-over-TCP API. See that add-on for port configuration (default localhost:9876).

REST Shim /tools/call

The REST API exposes a subset of the MCP tools so non-MCP clients (like the Blender add-on) can call them. Requests must include an X-Token header if MCP_REST_TOKEN is set. The response format mirrors MCP content objects (text, json, image).

Health Check

GET /health returns { "ok": true } so deployment targets can monitor the process.

Development

• Run linting/formatting as desired (none enforced yet).
• The LiteLLM dependency keeps provider selection abstract; add more aliases in MODEL_MAP as needed.
• Additional tools can be exposed by adding @mcp.tool() functions and listing them in _HTTP_EXPOSED_TOOL_NAMES when required by the REST shim.