antigravity-skills-reference/skills/writing-skills/references/tier-2-expanded

description, metadata

description	metadata
When to use Tier 2 (Expanded) skill architecture.	tags tier-2 expanded multi-file

Tier 2: Expanded Skills

Multi-file skills for complex topics with multiple sub-concepts.

When to Use

• Multiple related concepts: Needs separation of concerns
• 200-1000 lines total: Too big for one file
• Needs reference files: Patterns, examples, troubleshooting
• Cross-linking: Users need to navigate between sub-topics

Structure

my-skill/
├── SKILL.md              # Overview + navigation
└── references/
    ├── core/
    │   ├── README.md     # Main concept
    │   └── api.md        # API reference
    ├── patterns/
    │   └── README.md     # Usage patterns
    └── troubleshooting/
        └── README.md     # Common issues

Example

The writing-skills skill itself is Tier 2:

writing-skills/
├── SKILL.md              # Decision tree + navigation
├── gotchas.md            # Tribal knowledge
└── references/
    ├── anti-rationalization/
    ├── cso/
    ├── standards/
    ├── templates/
    └── testing/

Progressive Disclosure

1. Metadata (~100 tokens): Name + description loaded at startup
2. SKILL.md (<500 lines): Decision tree + index
3. References (as needed): Loaded only when user navigates

Key Differences from Tier 1

Aspect	Tier 1	Tier 2
Files	1	5-20
Total lines	<200	200-1000
Decision logic	None	Simple tree
Token cost	Minimal	Medium (progressive)

Checklist

• SKILL.md has clear navigation links
• Each references/ subdir has README.md
• No circular references between files
• Decision tree points to specific files