Bonsai MCP

MCP serverCommunity

Connects an agent to an IFC model open in Blender and Bonsai: queries, quantity takeoff, screenshots and IfcOpenShell code. By Show2Instruct.

13 starsUpdated 3 months agoGitHub data from 5 Nov 2026

At a glance

Type: MCP server
Works with: Blender / Bonsai (IFC)
How it connects: Drives a running copy of the tool
Access: Can modify models
Tool versions: Blender 3.6 or newer (4.x recommended); Bonsai needed for the IFC tools
Operating systems: Windows, macOS, Linux
Needs a Blender / Bonsai (IFC) licence: No
Transport: Local (stdio)
AI clients documented: Claude Desktop, Claude Code, Cursor, VS Code, OpenAI Codex
Licence: MIT
Language: Python

What it can do

Fourteen tools, each marked as query or edit, including IFC element lists filtered by class, storey or IfcOpenShell selector, property sets and the site-building-storey-space tree.
Quantity takeoff of areas, volumes and lengths by IFC class, optionally per storey.
Runs IfcOpenShell or Bonsai API code with bpy blocked, plus a separate full-Python tool, and refreshes only the changed elements after an IFC edit instead of reloading the project.
Viewport captures by direction or per-storey plan, with colour-by-class shading, for visual checks.

Limitations

The bridge listens on 127.0.0.1 without authentication and execute_blender_code runs any Python, so the authors say to treat it like an open Python prompt and keep it off networks.
Not on PyPI; you run it from a cloned copy of the repository.
Independent of the Bonsai project and the Blender Foundation.

Install

claude mcp add bonsai-mcp -- uv run --directory /path/to/bonsai-mcp bonsai-mcp

Source: github.com/Show2Instruct/bonsai-mcp#2-connect-your-client

{
  "mcpServers": {
    "bonsai-mcp": {
      "command": "uv",
      "args": ["run", "--directory", "/path/to/bonsai-mcp", "bonsai-mcp"]
    }
  }
}

Source: github.com/Show2Instruct/bonsai-mcp#2-connect-your-client

Clone the repository, install blender_addon/bonsai_bridge.py (or the bonsai_mcp_bridge zip from a release) through Edit > Preferences > Add-ons > Install from Disk, enable Bonsai MCP Bridge, then press N and click Start Bridge on the Bonsai MCP tab.

Source: github.com/Show2Instruct/bonsai-mcp#1-install-the-blender-add-on

MCP servers and skills run code on your computer. Review the source before installing.

AI-generated models, drawings and results must be checked by a qualified engineer before use.