wcag-audit-perceivable-color-blindness

When to Use

Use this tool when designing color schemes to ensure accessibility for users with color vision deficiencies, testing color-dependent information, or validating color contrast for different types of color blindness.

Usage

Command Line

node scripts/simulate.js --color "#FF0000" --type protanopia
node scripts/simulate.js --color "rgb(255,0,0)" --type deuteranopia
node scripts/simulate.js --color "#00FF00" --type tritanopia

JSON Input

node scripts/simulate.js --json '{"color": "#FF0000", "type": "protanopia"}'

Parameters

• --color: Color to simulate (hex, rgb)
• --type: Type of color blindness (protanopia, deuteranopia, tritanopia)
• --json: JSON input with color and type properties

Supported Color Blindness Types

• Protanopia: Red-blind (missing red cones)
• Deuteranopia: Green-blind (missing green cones)
• Tritanopia: Blue-blind (missing blue cones)

Output

Returns JSON with simulated color values:

{
  "original": "#FF0000",
  "simulated": "#5A5A5A",
  "type": "protanopia",
  "description": "Red-blind simulation"
}

Examples

Simulate red color for protanopia

$ node scripts/simulate.js --color "#FF0000" --type protanopia
Original: #FF0000 (rgb(255,0,0))
Protanopia: #5A5A5A (rgb(90,90,90))
This red appears as a dark gray to someone with protanopia

Test multiple colors

$ node scripts/simulate.js --color "#00FF00" --type deuteranopia
Original: #00FF00 (rgb(0,255,0))
Deuteranopia: #8C8C8C (rgb(140,140,140))
This green appears as a medium gray to someone with deuteranopia

Best Practices

1. Don't rely on color alone: Use shapes, patterns, or text labels in addition to color
2. Test critical color combinations: Check that important information remains distinguishable
3. Consider contrast: Even with color blindness simulation, ensure adequate contrast ratios
4. Test all types: Check designs against all three main types of color blindness

Learn More

For more information about Agent Skills and how they extend AI capabilities.