MCP Connector Grasshopper Documentation
How to install, configure, and use MCP Connector Grasshopper to connect AI clients like Claude Desktop, Claude Code, and Cursor to Grasshopper via Model Context Protocol.
Requirements
- Rhino 7 or Rhino 8 with Grasshopper 1
- Windows (64-bit)
Rhino 7 or Rhino 8 is required. Rhino 5 and 6 are not supported. Rhino 8 also runs inside Revit via Rhino.Inside.Revit, and the connector works there too. On Rhino 7, script components are limited to Python; C# script components need Rhino 8.
AI Applications
- Claude Desktop
- Claude Code
- Cursor
- Any other MCP client (via manual configuration below)
Installation
Close Rhino before starting the installation.
Manual Configuration
Claude Desktop and Cursor are configured automatically by the installer. For any other MCP client, add this to its MCP server configuration:
{
"mcpServers": {
"AUTOM8LABS_Grasshopper": {
"command": "C:\\ProgramData\\AUTOM8LABS\\MCPConnectorGrasshopper\\Bridge\\MCPConnectorGrasshopper.Bridge.exe"
}
}
}After changing MCP configuration, restart the AI client completely for the changes to take effect.
Trial and Licence
The 14-day trial
Every install starts with a free 14-day trial of all 24 tools. The trial starts automatically the first time a tool runs, and it needs an internet connection to start. It is tracked per machine on the licence server, so reinstalling does not reset it. During the trial, up to 7 days offline is tolerated.
When the trial ends, the connector locks. Every tool returns a purchase prompt until a licence is activated.
Activating a licence
After purchase, your licence key arrives by email. Activate it once from a terminal:
"C:\ProgramData\AUTOM8LABS\MCPConnectorGrasshopper\Bridge\MCPConnectorGrasshopper.Bridge.exe" --activate YOUR-KEY
One activation covers every AI client on the machine: Claude Desktop, Cursor, and Claude Code. Use --status to check the current trial or licence state, and --deactivate to release the seat before moving to another machine.
Once activated, the licence does not need a constant internet connection - short offline stretches never block your work.
Quickstart
Grasshopper in the Rhino command line or use the toolbar. The connector loads with the plugin.Every AI action is recorded as a single named undo step ("MCP: <tool>"). If you do not like what the AI did, one Ctrl-Z rolls it back.
Tool Reference (24)
All 24 tools are available during the 14-day trial and with a licence. See Trial and Licence.
| Tool | Example prompt |
|---|---|
| Test the connection between the AI client and Grasshopper | |
ping | Ping Grasshopper and tell me if you are connected |
| Read the current canvas: components, wires, and error states | |
get_canvas_state | What is on the canvas right now, and is anything erroring? |
| Search available components across all installed plugins | |
search_components | Find me a component that builds a Voronoi diagram |
| Inspect a component's inputs, outputs, and settings | |
get_component_info | What inputs and outputs does the selected component have? |
| Place new components on the canvas | |
create_components | Place a Number Slider, a Circle, and an Extrude on the canvas |
| Wire component outputs to inputs | |
connect_components | Wire the slider output into the circle radius |
| Remove components from the canvas | |
delete_components | Delete the components I have selected |
| Set sliders, panels, toggles, and value lists | |
set_values | Set the radius slider to 250 and its range to 50 up to 500 |
| Apply data-tree operations such as graft and flatten | |
set_data_tree | Graft the point output so each branch stays separate |
| Recompute the definition | |
run_solution | Recompute the definition and tell me if anything fails |
| Read computed output values after a solve | |
get_output_values | What values is the last component outputting? |
| Capture the Grasshopper canvas as an image | |
capture_canvas | Capture the canvas so I can see how the definition is wired |
| Capture the Rhino viewport as an image | |
capture_viewport | Capture the Rhino viewport and tell me what the geometry looks like |
| Create, edit, and remove canvas groups | |
manage_groups | Group the tower components together and label the group Tower Massing |
| Tidy the canvas with automatic layout | |
auto_layout | Tidy the canvas so nothing overlaps |
| List layers in the open Rhino document | |
get_rhino_layers | List the layers in the open Rhino document |
| Start a new, empty definition | |
new_definition | Start a new empty definition |
| Open a saved Grasshopper definition | |
open_definition | Open C:\Project\GH\facade-panels.gh |
| Save the current definition | |
save_definition | Save the definition to C:\Project\GH\tower-v2.gh |
| Get a structured digest of any definition | |
get_definition_summary | Summarise what this definition does before I change anything |
| Bring Rhino curves, breps, and meshes into the definition | |
reference_rhino_geometry | Reference the curves on the Rhino layer SITE-BOUNDARY into the definition |
| Bake results to Rhino layers | |
bake_geometry | Bake the panel results to a Rhino layer called FACADE-PANELS |
| Write a new Python script component on the canvas | |
create_script_component | Add a Python component that takes a list of points and returns the ones above Z=10000 |
| Edit an existing Python script component | |
edit_script_component | Edit the Python component so it also returns the count |
FAQ
Changelog
Rhino 7 support and faster builds
- Rhino 7 is now supported alongside Rhino 8 - one install covers both
- Faster, more efficient definition building in every AI client
- The installer can now be driven entirely from the keyboard - Enter activates the highlighted action on every screen, complementing the fix for small or scaled displays
- On Rhino 7, script components are limited to Python; C# script components need Rhino 8
Installer improvements
- Silent installation support for enterprise deployment. No changes to the connector itself
Reliability update for Claude
- Fixed an issue where the connector's tools could stop appearing in Claude Desktop and Claude Code while Grasshopper was open. All 24 tools now show reliably, whether Rhino is open or closed
- Recommended update for everyone using the connector with Claude. No changes to the tools themselves, and no action needed after installing
ChatGPT desktop support
- The installer now sets up ChatGPT desktop automatically, alongside Claude Desktop and Cursor
First release
- 24 tools to build, inspect, run and repair Grasshopper definitions with natural language in Rhino 8, including Grasshopper running inside Revit via Rhino.Inside
- Full feature set free for 14 days, no sign-up and no card required