Host Programs
How the assistant acts in Rhino — typed steps from a fixed list, checked on the server and again in Rhino, with deletes waiting for your approval.
Preview, Wrengler Pro. Host programs run from the assistant in the Wrengler panel in Rhino. The assistant on the web has no Rhino to act in, so it only answers.
Ask the assistant in Rhino to select the towers, colour the south-facing facades or hide the context, and it doesn't describe how you'd do it. It does it. What it sends Rhino is a host program: a short list of typed steps, each one an operation from a fixed vocabulary the plug-in publishes. It never generates code, only data the plug-in already knows how to run.
The operations
The assistant can use these eight operations and nothing else. Each is tagged with its effect, and the effect, not the operation, decides whether you're asked first.
| Operation | What it does | Effect |
|---|---|---|
host.selection.get | Read the current selection | read |
host.groups.list | List the geometry groups and how many objects each has | read |
host.measure.area | Measure floor, facade and roof area and GFA | read |
host.filter.facing | Keep the objects that face north, south, east, west, up or down (within 45° by default) | read |
host.select | Select objects by id, group or layer | reversible |
host.color.set | Set the display colour of objects | reversible |
host.visibility.set | Hide, show or isolate objects | reversible |
host.delete | Delete objects, after you approve | destructive |
Each operation acts on objects by id, by group or by layer. With none of these, it acts on the current selection.
host.groups.list and host.measure.area use the same code as the panel's group list and area
readouts, so the assistant and the panel can't disagree about a number.
Programs
A program has up to 12 steps. A step can use what an earlier step returned, like the ids that
host.filter.facing kept, by referring to it as {"$ref": "s1.ids"}. Steps run in order, and the
program stops at the first one that fails: Stopped at a failed step: …
The fast path. For a simple request like select the podium or hide the context layer, Wrengler can skip the language model entirely. It reads the one operation and its arguments straight from your message and runs it. That only happens when the operation is a plain, reversible Rhino action and Wrengler is at least 80% confident it read you right. A delete never takes the fast path.
Checked twice
- On the server, before it's sent. An unknown operation, a missing or mistyped argument, a bad colour, or a step that refers to a later step: any of these and the program is refused before it reaches Rhino. The assistant is told why and can try again.
- In Rhino, before it runs. The plug-in checks everything again, whatever sent it, and runs nothing unless every step is valid.
Before either, the usual checks apply: you're signed in, you're on Pro, you haven't hit the message limit, you can see the project, and your organization hasn't turned the assistant off.
Deletes wait for you
A program that deletes anything is shown before it runs:
- The objects are highlighted in Rhino, and the chat says Deletes 3 objects — highlighted in Rhino. One Ctrl+Z undoes it.
- Approve runs it. Dismiss runs nothing: Dismissed — nothing ran.
- If the model changes between the preview and your approval, nothing runs: The model changed after the preview, so what you approved may no longer be what would run. It previews again.
- Rhino refuses a delete that arrives without your approval, whoever sent it.
Undo
A program that changes the model runs as one undo record in Rhino, named Wrengler: assistant program. When it's done, the chat says Done · Undo in Rhino with Ctrl+Z. There's no undo button in the chat; use Ctrl+Z in Rhino. A program that only selects has nothing to undo.
After it runs
What the program measured, such as counts, areas and ids, comes back to the assistant as measured facts, and it answers from them. Wrengler then checks whether the program did what you asked. If not, the assistant may offer one repair, never more.
Each run carries an id, so a request that's retried doesn't run twice. A card from a conversation you reopen later can't be run again: Not run — the conversation closed before this ran.
Not yet
- Running studies. There's no study operation, so the assistant can't start a sunlight, view or radiation study. Run those from the panel.
- Other Rhino actions. Only the eight operations above. Moving, copying and editing geometry aren't in the vocabulary.
- Other hosts. Rhino only.
Related
- Harness Overview: one gate for every caller.
- Assistant: chips, sources and privacy.
- Goals: agents that work through a project's data toward a goal.