Runchat Docs

A CAD tool is a button on your Runchat toolbar in Rhino. Ask the agent to build one, publish it, and anyone you share it with can install it from its page. No compiling, no .rhp files, no Yak packages.

A Rhino app tool docked beside the viewport, showing the model's units and object count and a capture of the viewport

CAD tools come in two kinds:

Kind	What clicking it does	Use it when
Script	Runs a Python or C# script in your active document	One click is enough: work on the current selection and finish
App	Opens an HTML app in a dockable Rhino panel	The tool needs inputs, a preview, or an AI model

CAD tools need Rhino 8 or later and Runchat for Rhino 0.3.79 or later. See Runchat for Rhino to install the plugin.

Create a tool

Describe the tool to the agent, in the Runchat panel in Rhino or in any editor. For example:

Make a Rhino tool that offsets the selected surfaces by 200 mm and puts the results on a new layer called Offsets.

Make a Rhino app tool that captures my viewport, renders it as a watercolour sketch, and lets me import the result back into Rhino.

The agent writes the tool as a CAD Tool artifact and installs it for you. With the Runchat panel open in Rhino, the button appears on your Runchat toolbar within a few seconds, and updates each time the agent changes the tool. If the button doesn’t do what you expected, keep chatting and the agent updates the same tool.

Describe the tool

Say what it should work on (the selection, a layer, the whole model) and what it should produce. The agent asks if anything is unclear.

Try it in Rhino

Click the new button on the Runchat toolbar, or type its alias (for example RC_OffsetFacade) on the command line.

Iterate

Paste screenshots or command line errors back into the chat. Each change is picked up the next time the Runchat panel connects.

Publish and share

Publish the tool so teammates or the public can install it from its page.

Use a tool in Rhino

Installed tools appear as buttons on the Runchat toolbar, which you can dock like any other Rhino toolbar.

Click a button to run the tool.
Type the alias on the command line to run it without the toolbar, or use it in your own macros.
Right-click a button to open the tool’s docs.

App panels

An app tool opens in a Rhino panel named Runchat App 1 to Runchat App 4. The panel tab shows the tool’s icon. Drag the tab to dock it next to Layers or Properties, float it, or open two apps side by side. Close a panel with Rhino’s own tab close button; the next app you open reuses the slot.

An app tool docked in a Runchat App panel next to the Rhino viewport, showing the model's units, object count and active view

Docked app panels come back with their app when you restart Rhino. App panels share the Runchat panel’s sign-in, so apps can run your published workflows and use your credits without signing in again.

Find and install tools

Every tool has a public page with its icon, description, docs and an Install button. Click Install and the tool appears on your toolbar the next time the Runchat panel is open in Rhino. Click Installed — remove on the same page to take it off. To find your own and your team’s CAD tools, open the Artifacts dashboard and set Type to CAD Tool. A CAD tool is an artifact, so it is published the same way:

Draft tools work only for you. You don’t need to publish a script tool to use it yourself.
App tools must be published before they open in Rhino, because the panel loads the tool’s page.
Set Visibility from the tool’s … menu on the Artifacts dashboard: Team shares it with your teammates, Public lists it in the gallery.

Anyone who installs a tool runs it in their own Rhino with their own account: an app tool’s model runs are billed to the person using it.

How a tool is built

You don’t need to write any of this yourself, but it helps to know what the agent produces when you want to edit a tool by hand. A CAD tool artifact is a folder of files with a tool.json manifest:

{
  "name": "Offset Facade",
  "alias": "RC_OffsetFacade",
  "tooltip": "Offsets the selected surfaces by 200 mm",
  "icon": "icon.svg",
  "docs": "README.md",
  "action": { "kind": "script", "language": "python", "entry": "main.py" }
}

{
  "name": "Sketch Render",
  "alias": "RC_SketchRender",
  "tooltip": "Render the viewport as a sketch and import it",
  "icon": "icon.svg",
  "docs": "README.md",
  "action": { "kind": "app", "entry": "index.html" }
}

Field	Meaning
`name`	Shown on the tool page and as the button’s label
`alias`	The command name you can type in Rhino. Letters, digits and `_`, starting with a letter
`tooltip`	Shown when you hover the button
`icon`	An SVG file, drawn at toolbar size in light and dark themes. Simple shapes with solid fills work best
`docs`	A Markdown file shown on the tool page and opened when you right-click the button
`action`	`script` with a `language` (`python` or `csharp`) and an `entry` file, or `app` with an HTML `entry` file

Script tools

A script tool runs with no inputs, so it works from what’s selected and reports back on the command line:

main.py

import rhinoscriptsyntax as rs
import Rhino

ids = rs.SelectedObjects()
if not ids:
    Rhino.RhinoApp.WriteLine("Select some surfaces first, then run Offset Facade.")
else:
    layer = rs.AddLayer("Offsets")
    for id in ids:
        offset = rs.OffsetSurface(id, 200)
        if offset:
            rs.ObjectLayer(offset, layer)

Scripts run inside Rhino’s own Python 3 and C# environment, so they can use anything RhinoCommon offers, and each run is a single undo step.

App tools

An app tool is a Runchat app artifact with one extra: runchat.rhino reaches the Rhino of whoever is using it.

Method	Returns
`runchat.rhino.context()`	Units, object counts, the selection and the active view
`runchat.rhino.capture({ view, display_mode, width, height })`	`{ url, metadata }`: an uploaded viewport image
`runchat.rhino.exportSelection({ scope })`	`{ url, objects, bounds, units }`: a GLB of the `"selection"`, a `"layer"` or `"all"`
`runchat.rhino.runScript(code, { language })`	`{ success, message, output }`. Set `runchat_result` in the script to return data
`runchat.rhino.importModel(url)`	Imports a `.glb` (as meshes) or `.svg` (as curves) into the document, on the current layer

A typical app captures or exports from Rhino, runs a published workflow with runchat.run, and imports the result:

index.html

const shot = await runchat.rhino.capture({ display_mode: "Shaded", width: 1024 });
const result = await runchat.run("YOUR_WORKFLOW_ID", { image: shot.url });
await runchat.rhino.importModel(result.model);

runchat.rhino only works for signed-in people who have installed the tool and have Rhino open with the Runchat panel connected. Anywhere else, its calls fail with a message saying why.

Troubleshooting

An app tool says it has no app page yet

App tools open their published page. Publish the tool and the toolbar picks up the page within a few seconds.

A script tool fails

Errors and the traceback are printed on the Rhino command line. Copy them into the chat and the agent will fix the script.

Get Started

Plugins

Clipchat

Core Concepts

Node Reference

Examples

Rhino Tools

Create a tool

Use a tool in Rhino

App panels

Find and install tools

How a tool is built

Script tools

App tools

Troubleshooting

​Create a tool

​Use a tool in Rhino

​App panels

​Find and install tools

​Publish and share

​How a tool is built

​Script tools

​App tools

​Troubleshooting

Create a tool

Use a tool in Rhino

App panels

Find and install tools

Publish and share

How a tool is built

Script tools

App tools

Troubleshooting