Lists multiple specific concrete patterns (Factory, Builder, Strategy, Observer, Decorator) and specifies Java examples, clearly describing what the skill provides.

Clearly answers both what (common design patterns with Java examples) and when (explicit 'Use when' clause with specific trigger phrases and use case scenario).

Includes natural trigger phrases users would say: 'implement pattern', 'use factory', 'strategy pattern', plus the contextual trigger 'designing extensible components' which captures intent-based queries.

Highly distinctive with clear niche around design patterns specifically in Java context; trigger terms like 'factory', 'strategy pattern', 'implement pattern' are unlikely to conflict with other skills.

While the content is well-organized and avoids explaining basic concepts, it's quite lengthy at ~500 lines. Some patterns include multiple implementation variants (e.g., Spring alternatives) that could be split into separate reference files rather than inline.

Excellent executable code examples throughout. Every pattern includes complete, copy-paste ready Java code with clear usage examples. The anti-pattern comparisons (❌ vs ✅) provide concrete guidance on what to avoid.

For a reference skill, workflow clarity is appropriate. The quick reference table at the top provides clear decision guidance, and each pattern section follows a consistent structure: use case, code example, usage demonstration.

The skill mentions related skills at the end but keeps all pattern implementations inline rather than splitting detailed examples into separate files. The Spring alternatives and multiple variants per pattern could be in linked reference files.