Files
Claude-Code-Workflow/.claude/commands/workflow/ui-design/style-extract.md
catlog22 d213885f52 Refactor layout and style extraction workflows for multi-selection capabilities
- Updated `layout-extract` command to support user multi-selection of layout concepts, allowing for multiple layout templates to be generated based on user preferences.
- Revised argument hints and output structures to reflect changes in selection handling and output file formats.
- Enhanced user interaction by enabling multi-select options in both layout and style extraction phases.
- Streamlined the generation of layout templates and design systems to accommodate multiple selected variants, improving flexibility and user experience.
- Adjusted validation and output verification processes to ensure consistency with new multi-selection features.
2025-11-08 23:23:06 +08:00

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---
name: style-extract
description: Extract design style from reference images or text prompts using Claude analysis with variant generation
argument-hint: "[--base-path <path>] [--session <id>] [--images "<glob>"] [--urls "<list>"] [--prompt "<desc>"] [--variants <count>]"
allowed-tools: TodoWrite(*), Read(*), Write(*), Glob(*), mcp__chrome-devtools__navigate_page(*), mcp__chrome-devtools__evaluate_script(*)
---
# Style Extraction Command
## Overview
Extract design style from reference images or text prompts using Claude's built-in analysis. Directly generates production-ready design systems with complete `design-tokens.json` and `style-guide.md` for each variant.
**Strategy**: AI-Driven Design Space Exploration
- **Claude-Native**: 100% Claude analysis, no external tools
- **Direct Output**: Complete design systems (design-tokens.json + style-guide.md)
- **Flexible Input**: Images, text prompts, or both (hybrid mode)
- **Maximum Contrast**: AI generates maximally divergent design directions
- **Production-Ready**: WCAG AA compliant, OKLCH colors, semantic naming
## Phase 0: Setup & Input Validation
### Step 1: Detect Input Mode, Extraction Mode & Base Path
```bash
# Detect input source
# Priority: --urls + --images + --prompt → hybrid-url | --urls + --images → url-image | --urls → url | --images + --prompt → hybrid | --images → image | --prompt → text
# Parse URLs if provided (format: "target:url,target:url,...")
IF --urls:
url_list = []
FOR pair IN split(--urls, ","):
IF ":" IN pair:
target, url = pair.split(":", 1)
url_list.append({target: target.strip(), url: url.strip()})
ELSE:
# Single URL without target
url_list.append({target: "page", url: pair.strip()})
has_urls = true
primary_url = url_list[0].url # First URL as primary source
ELSE:
has_urls = false
# Set variants count (default: 3, range: 1-5)
# Behavior: Generate N design directions → User multi-select → Generate selected variants
variants_count = --variants OR 3
VALIDATE: 1 <= variants_count <= 5
# Determine base path (auto-detect and convert to absolute)
relative_path=$(find .workflow -type d -name "design-run-*" | head -1)
base_path=$(cd "$relative_path" && pwd)
bash(test -d "$base_path" && echo "✓ Base path: $base_path" || echo "✗ Path not found")
# OR use --base-path / --session parameters
```
### Step 2: Extract Computed Styles (URL Mode - Auto-Trigger)
```bash
# AUTO-TRIGGER: If URLs are available (from --urls parameter or capture metadata), automatically extract real CSS values
# This provides accurate design tokens to supplement visual analysis
# Priority 1: Check for --urls parameter
IF has_urls:
url_to_extract = primary_url
url_source = "--urls parameter"
# Priority 2: Check for URL metadata from capture phase
ELSE IF exists({base_path}/.metadata/capture-urls.json):
capture_urls = Read({base_path}/.metadata/capture-urls.json)
url_to_extract = capture_urls[0] # Use first URL
url_source = "capture metadata"
ELSE:
url_to_extract = null
# Execute extraction if URL available
IF url_to_extract AND mcp_chrome_devtools_available:
REPORT: "🔍 Auto-triggering URL mode: Extracting computed styles from {url_source}"
REPORT: " URL: {url_to_extract}"
# Read extraction script
script_content = Read(~/.claude/scripts/extract-computed-styles.js)
# Open page in Chrome DevTools
mcp__chrome-devtools__navigate_page(url=url_to_extract)
# Execute extraction script directly
result = mcp__chrome-devtools__evaluate_script(function=script_content)
# Save computed styles to intermediates directory
bash(mkdir -p {base_path}/.intermediates/style-analysis)
Write({base_path}/.intermediates/style-analysis/computed-styles.json, result)
computed_styles_available = true
REPORT: " ✅ Computed styles extracted and saved"
ELSE:
computed_styles_available = false
IF url_to_extract:
REPORT: "⚠️ Chrome DevTools MCP not available, falling back to visual analysis"
```
**Extraction Script Reference**: `~/.claude/scripts/extract-computed-styles.js`
**Usage**: Read the script file and use content directly in `mcp__chrome-devtools__evaluate_script()`
**Script returns**:
- `metadata`: Extraction timestamp, URL, method
- `tokens`: Organized design tokens (colors, borderRadii, shadows, fontSizes, fontWeights, spacing)
**Benefits**:
- ✅ Pixel-perfect accuracy for border-radius, box-shadow, padding, etc.
- ✅ Eliminates guessing from visual analysis
- ✅ Provides ground truth for design tokens
### Step 3: Load Inputs
```bash
# For image mode
bash(ls {images_pattern}) # Expand glob pattern
Read({image_path}) # Load each image
# For text mode
# Validate --prompt is non-empty
# Create output directory
bash(mkdir -p {base_path}/style-extraction/)
```
### Step 3: Memory Check
```bash
# 1. Check if inputs cached in session memory
IF session_has_inputs: SKIP Step 2 file reading
# 2. Check if output already exists
bash(test -f {base_path}/style-extraction/style-1/design-tokens.json && echo "exists")
IF exists: SKIP to completion
```
---
**Phase 0 Output**: `input_mode`, `base_path`, `extraction_mode`, `variants_count`, `loaded_images[]` or `prompt_guidance`, `has_urls`, `url_list[]`, `computed_styles_available`
## Phase 1: Design Direction Generation
### Step 1: Load Project Context
```bash
# Load brainstorming context if available
bash(test -f {base_path}/.brainstorming/role analysis documents && cat it)
```
### Step 2: Generate Design Direction Options (Agent Task 1)
**Executor**: `Task(ui-design-agent)`
Launch agent to generate `variants_count` design direction options with previews:
```javascript
Task(ui-design-agent): `
[DESIGN_DIRECTION_GENERATION_TASK]
Generate {variants_count} maximally contrasting design directions with visual previews
SESSION: {session_id} | MODE: explore | BASE_PATH: {base_path}
## Input Analysis
- User prompt: {prompt_guidance}
- Visual references: {loaded_images if available}
- Project context: {brainstorming_context if available}
## Analysis Rules
- Analyze 6D attribute space: color saturation, visual weight, formality, organic/geometric, innovation, density
- Generate {variants_count} directions with MAXIMUM contrast
- Each direction must be distinctly different (min distance score: 0.7)
## Generate for EACH Direction
1. **Core Philosophy**:
- philosophy_name (2-3 words, e.g., "Minimalist & Airy")
- design_attributes (6D scores 0-1)
- search_keywords (3-5 keywords)
- anti_keywords (2-3 keywords to avoid)
- rationale (why this is distinct from others)
2. **Visual Preview Elements**:
- primary_color (OKLCH format)
- secondary_color (OKLCH format)
- accent_color (OKLCH format)
- font_family_heading (specific font name)
- font_family_body (specific font name)
- border_radius_base (e.g., "0.5rem")
- mood_description (1-2 sentences describing the feel)
## Output
Write single JSON file: {base_path}/.intermediates/style-analysis/analysis-options.json
Use schema from INTERACTIVE-DATA-SPEC.md (Style Extract: analysis-options.json)
CRITICAL: Use Write() tool immediately after generating complete JSON
`
```
### Step 3: Verify Options File Created
```bash
bash(test -f {base_path}/.intermediates/style-analysis/analysis-options.json && echo "created")
# Quick validation
bash(cat {base_path}/.intermediates/style-analysis/analysis-options.json | grep -q "design_directions" && echo "valid")
```
**Output**: `analysis-options.json` with design direction options
---
## Phase 1.5: User Confirmation (Explore Mode Only - INTERACTIVE)
**Purpose**: Allow user to select preferred design direction(s) before generating full design systems
### Step 1: Load and Present Options
```bash
# Read options file
options = Read({base_path}/.intermediates/style-analysis/analysis-options.json)
# Parse design directions
design_directions = options.design_directions
```
### Step 2: Present Options to User
```
📋 Design Direction Options
We've generated {variants_count} contrasting design directions for your review.
Please select the direction(s) you'd like to develop into complete design systems.
{FOR each direction in design_directions:
═══════════════════════════════════════════════════
Option {direction.index}: {direction.philosophy_name}
═══════════════════════════════════════════════════
Philosophy: {direction.rationale}
Visual Preview:
• Colors: {direction.preview.primary_color} (primary), {direction.preview.accent_color} (accent)
• Typography: {direction.preview.font_family_heading} (headings), {direction.preview.font_family_body} (body)
• Border Radius: {direction.preview.border_radius_base}
• Mood: {direction.preview.mood_description}
Design Attributes:
• Color Saturation: {direction.design_attributes.color_saturation * 100}%
• Visual Weight: {direction.design_attributes.visual_weight * 100}%
• Formality: {direction.design_attributes.formality * 100}%
• Innovation: {direction.design_attributes.innovation * 100}%
Keywords: {join(direction.search_keywords, ", ")}
Avoiding: {join(direction.anti_keywords, ", ")}
}
═══════════════════════════════════════════════════
```
### Step 3: Capture User Selection
```javascript
// Use AskUserQuestion tool for multi-selection
AskUserQuestion({
questions: [{
question: "Which design direction(s) would you like to develop into complete design systems?",
header: "Style Choice",
multiSelect: true, // Multi-selection enabled (default behavior)
options: [
{FOR each direction:
label: "Option {direction.index}: {direction.philosophy_name}",
description: "{direction.mood_description}"
}
]
}]
})
// Parse user response (array of selections, e.g., ["Option 1: ...", "Option 3: ..."])
selected_options = user_answer
// Check for user cancellation
IF selected_options == null OR selected_options.length == 0:
REPORT: "⚠️ User canceled selection. Workflow terminated."
EXIT workflow
// Extract option indices from array
selected_indices = []
FOR each selected_option_text IN selected_options:
match = selected_option_text.match(/Option (\d+):/)
IF match:
selected_indices.push(parseInt(match[1]))
ELSE:
ERROR: "Invalid selection format. Expected 'Option N: ...' format"
EXIT workflow
REPORT: "✅ Selected {selected_indices.length} design direction(s)"
```
### Step 4: Write User Selection File
```bash
# Create user selection JSON
selection_data = {
"metadata": {
"selected_at": "{current_timestamp}",
"selection_type": "multi",
"session_id": "{session_id}",
"selection_count": selected_indices.length
},
"selected_indices": selected_indices, // Array of selected indices
"refinements": {
"enabled": false
}
}
# Write to file
bash(echo '{selection_data}' > {base_path}/.intermediates/style-analysis/user-selection.json)
# Verify
bash(test -f {base_path}/.intermediates/style-analysis/user-selection.json && echo "saved")
```
### Step 5: Confirmation Message
```
✅ Selection recorded!
You selected {selected_indices.length} design direction(s):
{FOR each index IN selected_indices:
• Option {index} - {design_directions[index-1].philosophy_name}
}
Proceeding to generate {selected_indices.length} complete design system(s)...
```
**Output**: `user-selection.json` with user's multi-selection
## Phase 2: Design System Generation (Agent Task 2)
**Executor**: `Task(ui-design-agent)` for selected variant(s)
### Step 1: Load User Selection
```bash
# Read user selection
selection = Read({base_path}/.intermediates/style-analysis/user-selection.json)
selected_indices = selection.selected_indices # Array of selected indices
# Read the selected direction details from options
options = Read({base_path}/.intermediates/style-analysis/analysis-options.json)
selected_directions = [options.design_directions[i-1] for i in selected_indices] # 0-indexed array
actual_variants_count = selected_indices.length
REPORT: "📦 Generating {actual_variants_count} design system(s)..."
```
### Step 2: Create Output Directories
```bash
# Create directories for each selected variant
FOR index IN 1..actual_variants_count:
bash(mkdir -p {base_path}/style-extraction/style-{index})
```
### Step 3: Launch Agent Tasks (Parallel)
Generate design systems for ALL selected directions in parallel (max 5 concurrent):
```javascript
// Launch parallel tasks, one for each selected direction
FOR variant_index IN 1..actual_variants_count:
selected_direction = selected_directions[variant_index - 1] // 0-indexed
Task(ui-design-agent): `
[DESIGN_SYSTEM_GENERATION_TASK #{variant_index}/{actual_variants_count}]
Generate production-ready design system based on user-selected direction
SESSION: {session_id} | VARIANT: {variant_index}/{actual_variants_count} | BASE_PATH: {base_path}
USER SELECTION:
- Selected Direction: ${selected_direction.philosophy_name}
- Design Attributes: ${JSON.stringify(selected_direction.design_attributes)}
- Search Keywords: ${selected_direction.search_keywords.join(", ")}
- Anti-keywords: ${selected_direction.anti_keywords.join(", ")}
- Rationale: ${selected_direction.rationale}
- Preview Colors: Primary=${selected_direction.preview.primary_color}, Accent=${selected_direction.preview.accent_color}
- Preview Typography: Heading=${selected_direction.preview.font_family_heading}, Body=${selected_direction.preview.font_family_body}
- Preview Border Radius: ${selected_direction.preview.border_radius_base}
## Input Analysis
- Input mode: {input_mode} (image/text/hybrid${has_urls ? "/url" : ""})
- Visual references: {loaded_images OR prompt_guidance}
${computed_styles_available ? "- Computed styles: Use as ground truth (Read from .intermediates/style-analysis/computed-styles.json)" : ""}
## Generation Rules
- Develop the selected design direction into a complete design system
- Use preview elements as foundation and expand with full token coverage
- Apply design_attributes to all token values:
* color_saturation → OKLCH chroma values
* visual_weight → font weights, shadow depths
* density → spacing scale compression/expansion
* formality → typography choices, border radius
* organic_geometric → border radius, shape patterns
* innovation → token naming, experimental values
- Honor search_keywords for design inspiration
- Avoid anti_keywords patterns
- All colors in OKLCH format ${computed_styles_available ? "(convert from computed RGB)" : ""}
- WCAG AA compliance: 4.5:1 text contrast, 3:1 UI contrast
## Generate
Create complete design system in {base_path}/style-extraction/style-{variant_index}/
1. **design-tokens.json**:
- Complete token structure with ALL fields:
* colors (brand, surface, semantic, text, border) - OKLCH format
* typography (families, sizes, weights, line heights, letter spacing, combinations)
* typography.combinations: Predefined typography presets (heading-primary, heading-secondary, body-regular, body-emphasis, caption, label) using var() references
* spacing (0-24 scale)
* opacity (0, 10, 20, 40, 60, 80, 90, 100)
* border_radius (none to full)
* shadows (sm to xl)
* component_styles (button, card, input variants) - component presets using var() references
* breakpoints (sm to 2xl)
- All colors in OKLCH format
${extraction_mode == "explore" ? "- Start from preview colors and expand to full palette" : ""}
${extraction_mode == "explore" && refinements.enabled ? "- Apply user refinements where specified" : ""}
- Common Tailwind CSS usage patterns in project (if extracting from existing project)
2. **style-guide.md**:
- Design philosophy (${extraction_mode == "explore" ? "expand on: " + selected_direction.philosophy_name : "describe the reference design"})
- Complete color system documentation with accessibility notes
- Typography scale and usage guidelines
- Typography Combinations section: Document each preset (heading-primary, heading-secondary, body-regular, body-emphasis, caption, label) with usage context and code examples
- Spacing system explanation
- Opacity & Transparency section: Opacity scale usage, common use cases (disabled states, overlays, hover effects), accessibility considerations
- Shadows & Elevation section: Shadow hierarchy and semantic usage
- Component Styles section: Document button, card, and input variants with code examples and visual descriptions
- Border Radius system and semantic usage
- Component examples and usage patterns
- Common Tailwind CSS patterns (if applicable)
## Critical Requirements
- ✅ Use Write() tool immediately for each file
- ✅ Write to style-{variant_index}/ directory
- ❌ NO external research or MCP calls (pure AI generation)
- ✅ Maintain consistency with user-selected direction
`
```
**Output**: {actual_variants_count} parallel agent tasks generate 2 files each (design-tokens.json, style-guide.md)
## Phase 3: Verify Output
### Step 1: Check Files Created
```bash
# Verify all design systems created
bash(ls {base_path}/style-extraction/style-*/design-tokens.json | wc -l)
# Validate structure
bash(cat {base_path}/style-extraction/style-1/design-tokens.json | grep -q "colors" && echo "valid")
```
### Step 2: Verify File Sizes
```bash
bash(ls -lh {base_path}/style-extraction/style-1/)
```
**Output**: `variants_count × 2` files verified
## Completion
### Todo Update
```javascript
TodoWrite({todos: [
{content: "Setup and input validation", status: "completed", activeForm: "Validating inputs"},
{content: "Design space analysis (explore mode)", status: "completed", activeForm: "Analyzing design space"},
{content: "Design system generation (agent)", status: "completed", activeForm: "Generating design systems"},
{content: "Verify output files", status: "completed", activeForm: "Verifying files"}
]});
```
### Output Message
```
✅ Style extraction complete!
Configuration:
- Session: {session_id}
- Extraction Mode: {extraction_mode} (imitate/explore)
- Input Mode: {input_mode} (image/text/hybrid{"/url" if has_urls else ""})
- Variants: {variants_count}
- Production-Ready: Complete design systems generated
{IF has_urls AND computed_styles_available:
- 🔍 URL Mode: Computed styles extracted from {len(url_list)} URL(s)
- Accuracy: Pixel-perfect design tokens from DOM
}
{IF has_urls AND NOT computed_styles_available:
- ⚠️ URL Mode: Chrome DevTools unavailable, used visual analysis fallback
}
{IF extraction_mode == "explore":
Design Direction Selection:
- You selected: Option {selected_index} - {selected_direction.philosophy_name}
- Generated from {variants_count} contrasting design direction options
}
Generated Files:
{base_path}/style-extraction/
└── style-1/ (design-tokens.json, style-guide.md)
{IF computed_styles_available:
Intermediate Analysis:
{base_path}/.intermediates/style-analysis/computed-styles.json (extracted from {primary_url})
}
{IF extraction_mode == "explore":
{base_path}/.intermediates/style-analysis/analysis-options.json (design direction options)
{base_path}/.intermediates/style-analysis/user-selection.json (your selection)
}
Next: /workflow:ui-design:layout-extract --session {session_id} --targets "..."
OR: /workflow:ui-design:generate --session {session_id}
```
## Simple Bash Commands
### Path Operations
```bash
# Find design directory
bash(find .workflow -type d -name "design-run-*" | head -1)
# Expand image pattern
bash(ls {images_pattern})
# Create output directory
bash(mkdir -p {base_path}/style-extraction/)
```
### Validation Commands
```bash
# Check if already extracted
bash(test -f {base_path}/style-extraction/style-1/design-tokens.json && echo "exists")
# Count variants
bash(ls {base_path}/style-extraction/style-* -d | wc -l)
# Validate JSON structure
bash(cat {base_path}/style-extraction/style-1/design-tokens.json | grep -q "colors" && echo "valid")
```
### File Operations
```bash
# Load brainstorming context
bash(test -f .brainstorming/role analysis documents && cat it)
# Create directories (example for multiple variants)
bash(mkdir -p {base_path}/style-extraction/style-1)
bash(mkdir -p {base_path}/style-extraction/style-2)
bash(mkdir -p {base_path}/style-extraction/style-3)
# Verify output
bash(ls {base_path}/style-extraction/style-1/)
bash(test -f {base_path}/.intermediates/style-analysis/analysis-options.json && echo "saved")
```
## Output Structure
```
{base_path}/
├── .intermediates/ # Intermediate analysis files
│ └── style-analysis/
│ ├── computed-styles.json # Extracted CSS values from DOM (if URL available)
│ ├── analysis-options.json # Design direction options (explore mode only)
│ └── user-selection.json # User's selected direction (explore mode only)
└── style-extraction/ # Final design system
└── style-1/
├── design-tokens.json # Production-ready design tokens
└── style-guide.md # Design philosophy and usage guide
```
## design-tokens.json Format
```json
{
"colors": {
"brand": {"primary": "oklch(...)", "secondary": "oklch(...)", "accent": "oklch(...)"},
"surface": {"background": "oklch(...)", "elevated": "oklch(...)", "overlay": "oklch(...)"},
"semantic": {"success": "oklch(...)", "warning": "oklch(...)", "error": "oklch(...)", "info": "oklch(...)"},
"text": {"primary": "oklch(...)", "secondary": "oklch(...)", "tertiary": "oklch(...)", "inverse": "oklch(...)"},
"border": {"default": "oklch(...)", "strong": "oklch(...)", "subtle": "oklch(...)"}
},
"typography": {
"font_family": {...},
"font_size": {...},
"font_weight": {...},
"line_height": {...},
"letter_spacing": {...},
"combinations": {
"heading-primary": {"family": "var(--font-family-heading)", "size": "var(--font-size-3xl)", "weight": "var(--font-weight-bold)", "line_height": "var(--line-height-tight)", "letter_spacing": "var(--letter-spacing-tight)"},
"heading-secondary": {...},
"body-regular": {...},
"body-emphasis": {...},
"caption": {...},
"label": {...}
}
},
"spacing": {"0": "0", "1": "0.25rem", ..., "24": "6rem"},
"opacity": {"0": "0", "10": "0.1", "20": "0.2", "40": "0.4", "60": "0.6", "80": "0.8", "90": "0.9", "100": "1"},
"border_radius": {"none": "0", "sm": "0.25rem", ..., "full": "9999px"},
"shadows": {"sm": "...", "md": "...", "lg": "...", "xl": "..."},
"component_styles": {
"button": {
"primary": {"background": "var(--color-brand-primary)", "color": "var(--color-text-inverse)", "padding": "var(--spacing-3) var(--spacing-6)", "border_radius": "var(--border-radius-md)", "font_weight": "var(--font-weight-semibold)"},
"secondary": {...},
"tertiary": {...}
},
"card": {
"default": {"background": "var(--color-surface-elevated)", "padding": "var(--spacing-6)", "border_radius": "var(--border-radius-lg)", "shadow": "var(--shadow-md)"},
"interactive": {...}
},
"input": {
"default": {"border": "1px solid var(--color-border-default)", "padding": "var(--spacing-3)", "border_radius": "var(--border-radius-md)", "background": "var(--color-surface-background)"},
"focus": {...},
"error": {...}
}
},
"breakpoints": {"sm": "640px", ..., "2xl": "1536px"}
}
```
**Requirements**: OKLCH colors, complete coverage, semantic naming, WCAG AA compliance, typography combinations, component style presets, opacity scale
## Error Handling
### Common Errors
```
ERROR: No images found
→ Check glob pattern
ERROR: Invalid prompt
→ Provide non-empty string
ERROR: Claude JSON parsing error
→ Retry with stricter format
```
## Key Features
- **Auto-Trigger URL Mode** - Automatically extracts computed styles when --urls provided (no manual flag needed)
- **Direct Design System Generation** - Complete design-tokens.json + style-guide.md in one step
- **Hybrid Extraction Strategy** - Combines computed CSS values (ground truth) with AI visual analysis
- **Pixel-Perfect Accuracy** - Chrome DevTools extracts exact border-radius, shadows, spacing values
- **AI-Driven Design Space Exploration** - 6D attribute space analysis for maximum contrast
- **Variant-Specific Directions** - Each variant has unique philosophy, keywords, anti-patterns
- **Maximum Contrast Guarantee** - Variants maximally distant in attribute space
- **Flexible Input** - Images, text, URLs, or hybrid mode
- **Graceful Fallback** - Falls back to pure visual inference if Chrome DevTools unavailable
- **Production-Ready** - OKLCH colors, WCAG AA compliance, semantic naming
- **Agent-Driven** - Autonomous multi-file generation with ui-design-agent
## Integration
**Input**: Reference images or text prompts
**Output**: `style-extraction/style-{N}/` with design-tokens.json + style-guide.md
**Next**: `/workflow:ui-design:layout-extract --session {session_id}` OR `/workflow:ui-design:generate --session {session_id}`
**Note**: This command extracts visual style (colors, typography, spacing) and generates production-ready design systems. For layout structure extraction, use `/workflow:ui-design:layout-extract`.