ios-icon-gen

SKILL.md

iOS Icon Generator

Generate PNG icon imagesets for Xcode asset catalogs from two sources.

When to Activate

Generating icon assets for an iOS/macOS Xcode project

Searching for icons across open source collections

Creating PNG imagesets (1x, 2x, 3x) for asset catalogs

Replacing placeholder icons with production-quality assets

Matching existing icon styles in an Xcode project

Core Principles

1. Two Sources, One Output Format

Both sources produce identical Xcode-compatible imagesets. Choose based on need:

Source
Icons
Requires
Best for

Iconify API
275,000+ from 200+ collections
Internet
Wide selection, specific styles, open source icons

SF Symbols
5,000+ Apple symbols
macOS only
Apple-native style, offline use

2. Always Match Existing Style

Before generating, check the project's existing icons for size, color, and weight consistency.

3. Output Structure

Both methods produce a complete Xcode imageset:

<output-dir>/<asset-name>.imageset/
  Contents.json
  <asset-name>.png        # 1x (68px default)
  <asset-name>@2x.png     # 2x (136px default)
  <asset-name>@3x.png     # 3x (204px default)

Examples

Step 1: Assess Requirements

Determine icon needs: what the icon represents, preferred style, target color, and size.

If the project already has icons, check existing style:

# Check dimensions of existing icon
sips -g pixelWidth -g pixelHeight path/to/existing@2x.png

Step 2: Search for Icons

Iconify API (recommended for wide selection):

# Search all collections
$SKILL_DIR/scripts/iconify_gen.sh search "receipt"

# Search within a specific collection
$SKILL_DIR/scripts/iconify_gen.sh search "business card" --prefix mdi

# List available collections
$SKILL_DIR/scripts/iconify_gen.sh collections

SF Symbols (for Apple-native style):
Browse the SF Symbols app or reference common names:

Use Case
Symbol Name

Document
doc.text, doc.fill

Receipt
doc.text.below.ecg, receipt

Person
person.crop.rectangle, person.text.rectangle

Camera
camera, camera.fill

Scan
doc.viewfinder, qrcode.viewfinder

Settings
gearshape, slider.horizontal.3

Step 3: Preview (Optional)

# Iconify preview
$SKILL_DIR/scripts/iconify_gen.sh preview mdi:receipt-text-outline

Step 4: Generate

Iconify API:

# Basic generation
$SKILL_DIR/scripts/iconify_gen.sh mdi:receipt-text-outline editTool_expenseReport

# Custom color and output location
$SKILL_DIR/scripts/iconify_gen.sh mdi:receipt-text-outline myIcon --color 007AFF --output ./Assets.xcassets/icons

Options: --size <pt> (default: 68), --color <hex> (default: 8E8E93), --output <dir> (default: /tmp/icons)

SF Symbols:

# Basic generation
swift $SKILL_DIR/scripts/generate_icons.swift doc.text.below.ecg editTool_expenseReport

# Custom color, weight, and output
swift $SKILL_DIR/scripts/generate_icons.swift person.crop.rectangle myIcon --color 007AFF --weight regular --output ./Assets.xcassets/icons

Options: --size <pt> (default: 68), --color <hex> (default: 8E8E93), --weight <name> (default: thin), --output <dir> (default: /tmp/icons)

Step 5: Verify and Integrate

Read the generated @2x PNG to verify visually

Copy to asset catalog if not output there directly:
cp -r /tmp/icons/<name>.imageset path/to/Assets.xcassets/<group>/

Build the project to verify Xcode picks up the new assets

Popular Iconify Collections

Prefix
Name
Count
Style

mdi
Material Design Icons
7400+
Filled + outline variants

ph
Phosphor
9000+
6 weights per icon

solar
Solar
7400+
Bold, linear, outline

tabler
Tabler Icons
6000+
Consistent stroke width

lucide
Lucide
1700+
Clean, minimal

ri
Remix Icon
3100+
Filled + line variants

carbon
Carbon
2400+
IBM design language

heroicons
HeroIcons
1200+
Tailwind CSS companion

Browse all: https://icon-sets.iconify.design/

Scripts Reference

Script
Source
Path

iconify_gen.sh
Iconify API (275k+ icons)
$SKILL_DIR/scripts/iconify_gen.sh

generate_icons.swift
SF Symbols (5k+ icons)
$SKILL_DIR/scripts/generate_icons.swift

Best Practices

Search before generating -- browse available icons to find the best match

Match existing project style -- check dimensions, color, and weight of existing icons before generating new ones

Use Iconify for variety -- 200+ collections means you can find the exact style you need

Use SF Symbols for Apple consistency -- they match system UI perfectly

Generate directly to asset catalog -- use --output ./Assets.xcassets/icons to skip manual copying

Verify visually -- always preview the @2x PNG before committing

Anti-Patterns

Generating icons without checking existing project icon style

Using default colors when the project has a defined color palette

Generating at wrong sizes (check existing icons first)

Committing generated icons without visual verification