Connecting Claude to Rhino

With McNeel's official MCP connector, Claude no longer just answers: it acts in Rhino. You describe the result in plain language, it creates the geometry, sorts the layers and measures the model.

What you need

• Rhino 8, up to date (SR19 or later), on Windows or on an Apple silicon Mac.
• Claude Desktop, signed in to your account.
• Rhino-MCP-Platform, McNeel's plugin.

The 4 steps

1. Install the connector: download connector.mcpb from the McNeel docs, then in Claude Desktop: Settings › Extensions › Advanced settings › Install extension.
2. Install the Rhino plugin: in Rhino, type PackageManager, search for Rhino-MCP-Platform (McNeel) and install it. Restart Rhino, then type MCPStart to start the server.
3. Test the connection: in a new chat, a first very simple prompt. Claude asks for permission before acting in Rhino.
4. Prompt: describe the result with precise figures, then correct it in one sentence.

The prompts

Open a fresh Rhino doc and make me a box.

Replace the box with a 12-storey tower: 30 × 20 m slabs, 3.2 m between floors, each floor rotated 4°. Put the slabs on a "Slabs" layer.

Give me the area of one slab and the total.

The areas come from the model's geometry, not from an estimate. Open a new chat per project: Claude does not mix up files.

If it gets stuck

• "Unknown command: MCPStart": update Rhino, then run SetDotNetRuntime and pick NETCore 8.
• Claude can't see Rhino: restart Claude Desktop, then check in Settings › Extensions that Rhino3d is connected.
• Nothing shows up: Zoom Extents, check the layers and the open file.
• Two Rhino MCPs installed: keep only one (remove rhinomcp, for example).
• Intel Mac: not supported, Apple silicon Macs only.