The New Standard in AI Design: What is DESIGN.md? How to Write?

Maintaining visual consistency across UI design has always been a challenge in project development. Colors, fonts, and component styles usually live in Figma files, brand PDFs, or even a designer’s mind—but AI agents cannot interpret these. Enter DESIGN.md.

What is DESIGN.md?

DESIGN.md is a text-based design system document that defines your project’s visual rules. Both humans and AI can read and edit it, ensuring consistent UI generation across screens.

Benefits of DESIGN.md

When a design agent like Stitch reads your DESIGN.md, every screen it generates follows the same visual rules: color palette, typography, and component patterns. Without it, screens are inconsistent; with it, they feel cohesive.

DESIGN.md is not a static config file—it is a living document. The agent generates it, you refine it, and it is reapplied to screens as your design evolves.

How to Create a DESIGN.md

1. Let the Agent Generate It

Provide a prompt to an AI like Stitch, and it automatically generates a design system and summarizes it as DESIGN.md.

Example Prompt:

Code
A playful coffee shop ordering app with warm colors, rounded corners, and a friendly feel

The AI generates colors, typography, and component styles, and outputs a DESIGN.md.

2. Derive from Existing Branding

Provide a URL or image of your brand, and the AI extracts your palette, typography, and style patterns to create a DESIGN.md.

3. Write it by Hand

Advanced users can author a DESIGN.md directly in Markdown, specifying exact design rules. No special syntax or tooling is required.

Example DESIGN.md (Localized for English-Speaking Users)

Code
# Design System

## Overview
A focused, minimal dark interface for a developer productivity app.
Clean lines, low visual noise, and high information density.

## Colors
- **Primary** (#2665fd): Main CTA buttons, active states, important actions
- **Secondary** (#475569): Supporting UI, chips, secondary actions
- **Surface** (#0b1326): Page backgrounds
- **On-surface** (#dae2fd): Primary text on dark backgrounds
- **Error** (#ffb4ab): Validation errors, destructive actions

## Typography
- **Headlines**: Inter, semi-bold
- **Body**: Inter, regular, 14–16px
- **Labels**: Inter, medium, 12px, uppercase for section headers

## Components
- **Buttons**: Rounded (8px), primary buttons filled with brand blue
- **Inputs**: 1px border, subtle surface-variant background
- **Cards**: No elevation, relies on border and background contrast

## Do's and Don'ts
- Do use the primary color sparingly, only for the most important actions
- Don’t mix rounded and sharp corners in the same view
- Do maintain at least 4:1 contrast ratio for all text

By adopting DESIGN.md, you create a common design language for both humans and AI, ensuring visual consistency across your project and making AI-assisted UI generation practical and scalable.