hoppercode is a transparent, hackable modeling agent that inspects and edits your Grasshopper canvas and runs scripts against the Rhino document — over ZeroMQ, while Rhino is open.
01 —
Every tool call is visible. You watch the agent inspect the canvas, move components, and run scripts — no opaque black box between you and the model.
02 —
A Pi extension plus a Grasshopper plugin. Plain TypeScript over ZeroMQ. Fork it, read it, reshape the tools to fit how you actually model.
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Not a separate SaaS tab. The agent drives Rhino and Grasshopper directly — the same document you are working in, in real time.
§ Capabilities
Two tool surfaces — one for the Rhino document, one for the Grasshopper canvas. The agent picks what it needs.
rh_run_script Run Rhino commands, Python, or C# on the active document.
rh_query_objects List objects with short IDs for Grasshopper params.
gh_edit_components Add, move, and delete components on the canvas.
gh_edit_wire Connect or disconnect wires between components.
gh_create_widget Sliders, panels, toggles — generated on demand.
gh_get_canvas Read the canvas layout and component snapshot.
§ Quick start
Install via Pi
postinstall builds the C# plugin and copies it into your Grasshopper Libraries.
Restart Rhino
drop the Hopper Code Backend component (Params → Util) onto the canvas.
Talk to Pi
the gh_* and rh_* tools register automatically. Start modeling.
pi install npm:hopper-pi“You need Rhino 8, Pi, the .NET 7 SDK, and Node 20+. The agent runs edits as a single undoable Rhino transaction.”
⚠ Supercargo
This project is early in its own development. APIs, tools, and behavior will change without notice. It is built for people who want to read the source and break things — not for production pipelines you cannot afford to rebuild.