Blender MCP by ArchBench

Connect an MCP-compatible assistant to Blender. Read scene and selection context, then optionally run user-requested Python through Blender's native API.

Experimental alpha. Native acceptance tests passed on Blender 4.3.2 on macOS. Other Blender versions and interactive installation/viewport/Undo workflows remain unqualified. Use a disposable scene first. See validation.

The connector is independently implemented. It requires no ArchBench account, subscription, or desktop application and sends no telemetry.

Install

Prerequisites: Blender desktop, Node.js 22+, and Python 3 for building the add-on. The implementation targets Blender 3.6+, with the qualification limit above.

git clone https://github.com/3d-mcp/blender-mcp.git
cd blender-mcp
npm ci --ignore-scripts
npm run package:hosts

A prebuilt add-on is provided on the alpha release page. In Blender Preferences, install dist/blender-mcp-addon.zip (or the downloaded ZIP) using Add-ons → Install from Disk (wording varies by version), then enable the add-on. In the 3D View sidebar, open MCP and click Start MCP bridge. Leave Allow native scripts unchecked for read-only use. This is a legacy add-on distributed through GitHub, not a listing in Blender's official Extensions catalog.

Configure your MCP client using absolute paths, for example:

{
  "mcpServers": {
    "blender": {
      "command": "/absolute/path/to/node",
      "args": ["/absolute/path/to/blender-mcp/bin/blender-mcp.mjs"]
    }
  }
}

Client setup and troubleshooting. The client launches the stdio process; no separate server terminal is needed. Both processes must run on the same machine under the same OS user. There is no npm registry release yet.

First request

“Check my Blender connection and describe the current selection.”

To use scripting, stop the bridge, check Allow native scripts, and restart. Also set ARCHBENCH_MCP_ALLOW_SCRIPTS=1 in the MCP client's server environment. Each execution requires confirm: true. Example Python:

result = {"objects": len(bpy.context.scene.objects)}

Scripts have Blender's full authority, including file and network access. Return small JSON-compatible values in result. Timeout/cancellation can prevent queued work from starting but cannot interrupt a running script or undo its effects. Never automatically retry a mutation. Security and limits.

Development

npm run check
node scripts/test-blender-native.mjs /path/to/Blender

The first command runs MCP/transport regressions, source syntax and dependency checks, and verifies the packaged source and licenses. The second runs native acceptance tests in an isolated, unsaved scene. GitHub Actions runs the transport checks on Linux, macOS and Windows; those checks do not certify native Blender on all three operating systems.

License and ArchBench

The independent MCP server and shared transport are MIT. The Blender add-on is GPL-3.0-or-later; its archive includes all corresponding Python source and both license notices. See LICENSING.md for the exact file mapping.

Maintained by ArchBench, the separate product for AI-assisted design work. ArchBench's private modeling intelligence, project history, collaboration and workflow systems are not included here. The connector remains usable independently.

This is an independent integration, not an official Blender project.