Prompt

A prompt is like a work order for a contractor. If you just say "make it look nice," they'll go with their own idea. If you write "paint the living room walls light gray and keep the existing ceiling light," the result is much more predictable.

A good coding prompt usually includes: what to do (the goal), where (files, components), what's happening now (errors, screenshots, existing code), constraints (parts not to touch, the component library to stick with), and what done looks like (acceptance criteria).

Keep these apart: a prompt is what you send in each conversation. A System Prompt is the underlying instruction the tool sets up before the conversation starts. A Rules File lives in your project and gets attached to every conversation automatically as a long-term agreement. Anything you find yourself repeating belongs in a rules file.