One Prompt, One Demo: Solar System Explorer

I wanted a simple demo to show what a single prompt can produce with GPT 5.2. The result is static/planet-demo.html: a self-contained Solar System Explorer with a canvas renderer, a small control panel, and planet info cards. No build step. One file.

This is not a product. It is a proof of speed: idea to interactive artifact in minutes.

The prompt, in spirit

The ask was straightforward:

• One HTML file, no dependencies
• Interactive solar system with orbits and labels
• A small HUD with speed and zoom controls
• Click a planet to see a facts panel
• Simple keyboard shortcuts for pause and reset

That is the level of specificity that keeps the output coherent and useful.

The original prompt

Create a single-page app in a single HTML file with the following requirements:
- Name: Solar System Explorer
- Goal: Visualize planets orbiting the sun.
- Features: Click planets for info, orbit speed control, and, drag to rotate, zoom in/out.
- The UI should be dark-themed and interactive.

The demo

Why this matters

LLMs compress the time between concept and usable demo. That changes how you explore ideas:

• You can test an interaction before you commit to a stack
• You can validate a visual direction without a full design cycle
• You can show stakeholders something tangible on day one

The real work still matters, though. A prompt can draft a demo, but it does not decide the product boundaries, the UX tradeoffs, or how it fits into a real system. That is where engineering judgment still earns its keep.