The body is lean and assumes Claude's competence — it avoids explaining concepts Claude already knows and every line is direct guidance with no padding.

Concrete conventions ('Use `?watch=true` query param for SSE streaming', 'Use named ports (e.g., `port: mcp`)') and a specific output template give actionable, copy-ready guidance even without code, which is appropriate for an instruction-only skill.

A clearly sequenced five-step Process is laid out explicitly; this is a design/planning skill rather than a destructive or batch operation, so the absence of validation checkpoints does not cap the score.

Under 50 lines and single-purpose, it is organized into clear sections (Process, Principles, Conventions, Output) with no bundle files needed, satisfying the simple-skill allowance for a top score.

Names the domain ('Design architecture for Ark features') and a guiding approach ('following existing patterns and principles') but the stated actions are high-level rather than a comprehensive list of concrete actions; it stops short of enumerating multiple specific operations.

It explicitly answers both 'what' (design Ark architecture following existing patterns) and 'when' (an explicit 'Use when...' trigger clause), satisfying both halves of the completeness criterion.

The 'Use when planning new features, extending components, or evaluating technical approaches' clause supplies natural phrases a user would actually say when reaching for this skill, giving good trigger coverage.

Scoping to 'Ark features' gives it a clear niche with distinct triggers, making it unlikely to fire for unrelated skills.