Most of the body (Best Practices, Pitfalls, the code example) is efficient, but the 'Core Concepts' section explains basics Claude already knows ('Exceptions: Traditional try-catch, disrupts control flow', listing 'Network timeouts', 'Missing files' as recoverable), fitting 'mostly efficient but includes some unnecessary explanation'; not a 1 because the practical content is not padded, and not a 3 because of the conceptual filler.

It provides one fully executable, copy-paste-ready Python example with typed exceptions and error wrapping, plus concrete pitfalls, but the skill claims 'across languages' while only showing Python, and the 'Core Concepts' section is descriptive rather than instructional, fitting 'some concrete guidance but incomplete'; not a 3 due to single-language coverage and descriptive sections.

The numbered Best Practices and the process_order example imply a validate-then-handle sequence with implicit checkpoints, but the skill has no explicit sequenced workflow with validation/feedback steps at the instruction level, fitting 'sequence present but checkpoints missing or implicit'; not a 3 because there is no explicit validation checkpoint checklist for the skill's own process.

SKILL.md is a concise overview and clearly signals a one-level-deep reference ('Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.'); the referenced file exists and is one level deep, matching 'clear overview with well-signaled one-level-deep references'; not lower because navigation is explicit and the split is appropriate.

It names the domain ('error handling patterns across languages') and lists patterns ('exceptions, Result types, error propagation, and graceful degradation'), but these are topics rather than concrete executable actions like 'extract text' or 'fill forms', matching the 'names domain and some actions' anchor; it is not a 3 because no multiple specific concrete actions are listed.

It explicitly answers what ('Master error handling patterns... to build resilient applications') and when with an explicit 'Use when implementing error handling, designing APIs, or improving application reliability' trigger clause, matching the 'clearly answers both what AND when' anchor; the Use when clause is present so it is not capped at 2.

The natural term 'error handling' appears and triggers ('implementing error handling, designing APIs, improving application reliability') are reasonable, but common variations users would say (e.g. 'exception handling', 'try-catch', 'retry', 'circuit breaker') are absent, fitting 'some relevant keywords but missing common variations'; not a 3 due to limited variation coverage.

'error handling patterns' is a recognizable niche, but the secondary triggers 'designing APIs' and 'improving application reliability' are broad and could overlap with API-design or reliability skills, fitting 'somewhat specific but could still overlap'; not a 3 because the broad triggers create real conflict risk.