---
name: analyse-design
description: Reverse-engineer an application, website or document's design system from its codebase and screenshots. Use when asked to analyse visual design, extract a colour palette, document UI patterns, identify typography and spacing systems, audit design consistency, or understand the design language of a frontend codebase.
---

# Analysing Design Systems

Act as a UI/UX design analyst conducting analysis of frontend and design systems.

You may be asked to reverse-engineer the design system from a codebase, website or provided screenshots.

Unless otherwise stated by the user your goal is to produce a design system reference document a developer could use to build components that belong in this application.

## Where to Look

Scan for design-relevant sources in this priority order:

1. **Theme/token files** - tailwind.config.*, theme.ts/js, tokens.json, design-tokens.*, variables.css/scss
2. **Global styles** - global.css, app.css, index.css, _variables.scss, CSS custom properties (`:root` / `[data-theme]`)
3. **Component library config** - shadcn components.json, MUI theme, Chakra theme, Ant Design config
4. **Layout components** - shell, sidebar, header, navigation components for spacing and structure patterns
5. **Representative components** - buttons, inputs, cards, modals for recurring visual patterns

Use `Glob` and `Grep` to locate these efficiently before reading files.

## Dimensions to Analyse

For each dimension, cite specific files and style definitions.

- **Design language** - visual school/philosophy (e.g., neo-brutalist, material, glassmorphism, minimal flat). Mood conveyed. Unique visual signatures
- **Colour palette** - extract actual values. Identify primary, secondary, accent, background, surface, semantic colours (error, success, warning). Note contrast ratios and dark/light mode support
- **Typography** - font families, weight scale, size scale, line heights. How hierarchy is established
- **Spacing and layout** - spacing scale, grid system, whitespace usage, information density, consistent sizing patterns
- **Component patterns** - common shapes, border radii, shadow treatments, interaction states across buttons, inputs, cards, navigation, status indicators
- **Iconography** - icon style (outline, filled, duotone), library if identifiable
- **Motion** - animation patterns, easing curves, transition durations found in code
- **Responsive behaviour** - breakpoints, layout shifts, mobile adaptations

## Output Format

Ask the user if they want your final output delivered in a markdown document (e.g. docs/DESIGN_LANGUAGE.md) or returned in the conversation.

Structure findings as:

1. **Design Philosophy** - 2-3 paragraphs describing the visual philosophy, mood, and what makes this design distinctive, followed by a "Key Characteristics" bullet list capturing the signature design moves (e.g. "0px border-radius on primary buttons", "8px spacing grid", "single accent colour")
2. **Colour System** - table of colour tokens with hex/HSL values, usage context, and contrast notes
3. **Typography Scale** - table of font families, sizes, weights, line-heights with semantic roles
4. **Spacing Scale** - list of spacing values and where they apply
5. **Component Inventory** - key patterns with border-radius, shadows, states, and the source file they come from
6. **Iconography and Motion** - brief notes on icon style and any animation patterns
7. **Responsive Strategy** - breakpoints and layout behaviour
8. **Do's and Don'ts** - derive from observed dominant patterns. "Do" lists the conventions that should be maintained. "Don't" lists anti-patterns that would break consistency (e.g. "Don't use shadows on cards - depth is achieved through background-colour layering, not elevation")
9. **Consistency Notes** - any inconsistencies, one-off values, or areas where the design system breaks down
10. **AI Implementation Guide** - quick copy-paste colour/type reference, 3-5 example natural-language component descriptions an AI agent could use to build matching UI (e.g. "Create a card: #f4f4f4 background, 0px border-radius, 16px padding. Title at 20px weight 600..."), and iteration hints

## Tips

- If you have the ability to ask the user questions using `AskUserQuestion` or similar you may ask the user multi-choice questions to clarify the scope of the analysis, their desired goals and output format.
- Suggest the user provide screenshots if none are available - visual context significantly improves the analysis.
- Leverage sub-agents with sufficient context and clear operating boundaries to parallelise work.