Conciseness

The skill is reasonably efficient but has notable redundancy — the anti-patterns section largely repeats the same CORRECT/WRONG examples already shown in earlier sections (loading states, error handling, button states). The core principles list and some explanatory text (e.g., 'CRITICAL: Never swallow errors silently') add modest padding. The decision tree and skeleton vs spinner table are useful but could be tighter.

Actionability

Provides concrete, executable TypeScript/TSX code examples covering loading states, error handling, button states, empty states, and form submission. The code is copy-paste ready and covers common cases well. Minor gap: no import statements or framework context (e.g., which toast library, which UI component library), and the ErrorState component is illustrative but not tied to a specific design system.

Workflow Clarity

The loading state decision tree provides a clear sequence for handling UI states. The checklist at the end serves as a validation checkpoint. The form submission pattern shows a clear flow. However, there's no explicit feedback loop for error recovery beyond 'retry' buttons, and the overall document reads more as a pattern catalog than a step-by-step workflow, which is appropriate for this type of skill but lacks explicit validation steps for the component-building process.

Progressive Disclosure

The content is well-structured with clear headers and sections, but at ~200 lines it's a substantial amount of inline content with significant repetition (anti-patterns section). References to other skills (graphql-schema, testing-patterns, formik-patterns) are mentioned but not linked to actual files. No bundle files exist to offload detailed patterns. The skeleton vs spinner table and error hierarchy could be in separate reference files.

Specificity

Names the domain (React UI) and lists a few areas (loading states, error handling, data fetching), but these are more like categories than concrete actions. It doesn't specify what it actually does with these patterns (e.g., 'creates skeleton loaders', 'implements error boundaries', 'sets up React Query hooks').

Completeness

Has both 'what' (modern React UI patterns for loading states, error handling, data fetching) and 'when' (building UI components, handling async data, managing UI states). The 'when' clause is present and explicit but somewhat generic — 'building UI components' and 'managing UI states' are broad triggers that could apply to many skills.

Trigger Term Quality

Includes some relevant keywords like 'React', 'UI components', 'loading states', 'error handling', 'async data', and 'data fetching', but misses common natural terms users might say like 'spinner', 'skeleton', 'suspense', 'error boundary', 'useEffect', 'React Query', 'SWR', or 'fetch data'.

Distinctiveness Conflict Risk

While it specifies React and particular UI concerns, terms like 'UI components', 'UI states', and 'async data' are broad enough to overlap with general React component skills, state management skills, or API integration skills. The description doesn't carve out a sufficiently narrow niche.