# Archat

- **Event:** [Gemini 3 서울 해커톤](https://cerebralvalley.ai/e/gemini-3-seoul-hackathon)
- **When:** Sat, Feb 28 at 9:00 AM – 10:00 PM (GMT+9)
- **Where:** 서울 Seocho District, Olympic-daero, 2085-14 세빛둥둥섬
- **Team:** [Wiseong Cho](https://cerebralvalley.ai/u/escargot)
- **GitHub:** https://github.com/seeewd/hackathon.git
- **Demo video:** https://youtu.be/ZyTN17hOt1I
- **Gallery:** https://cerebralvalley.ai/e/gemini-3-seoul-hackathon/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/gemini-3-seoul-hackathon/hackathon/gallery/21

Archat is an AI tool that automatically generates Grasshopper node graphs from a single natural language sentence.

Core idea:

User types a natural language prompt like "make a cube with pentagonal roofs on its four sides"
Gemini AI generates DSL code consisting solely of node() / wire() function calls
The script extracts the code block from Gemini's response → validates safety via AST → executes in a sandbox
Nodes and wires are automatically placed on the Grasshopper canvas
Supports Archicad components (Wall, Slab, Column) as well
Technical highlights:

AST-based whitelist validation completely blocks arbitrary code execution
Chatbot UI (Eto.Forms) runs directly from Rhino ScriptEditor
Also available as a GhPython component running inside Grasshopper itself
No external library dependencies — standard library only

---

Markdown version of https://cerebralvalley.ai/e/gemini-3-seoul-hackathon/hackathon/gallery/21. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt