building-ui

Complete guide for building beautiful apps with Expo Router. Covers fundamentals, styling, components, navigation, animations, patterns, and native tabs.

Quality

57%

Does it follow best practices?

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tessl review fix ./src/ii_agent/settings/skills/builtin/expo-building-ui/SKILL.md

Quality

Content

56%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The skill is genuinely actionable with strong concrete examples and a well-organized reference structure, but it is padded with generic mobile-UX prose and redundancy that bloat the token budget. Trimming the design-system treatise and resolving internal contradictions (icons) would meaningfully improve it.

Suggestions

Move the 'UI/UX DESIGN SYSTEM' guideline blocks into a dedicated reference file and keep only a concise pointer in SKILL.md to reduce token bloat.

Resolve the icons contradiction: the Library Preferences and references say use SF Symbols / expo-symbols, while the inlined section mandates @expo/vector-icons.

Cut generic mobile-UX truisms (shadows for elevation, use clear error states, the welcome-screen color-profile list) that Claude already knows.

Dimension	Reasoning	Score
Conciseness	At 439 lines the body includes large 'MANDATORY' UX/design sections restating generic mobile-UX principles Claude already knows (e.g. shadows-for-elevation, error-state phrasing, a padded welcome-screen color-profile list), plus noticeable redundancy such as the icons section contradicting the references and Library Preferences.	2 / 5
Actionability	Mostly executable guidance with concrete, copy-paste-ready code blocks for Link, Stack, context menus, form sheets, and layouts; minor gaps where some design sections give only abstract rules without code.	4 / 5
Workflow Clarity	The 'Running the App' section gives a clear sequenced flow (Expo Go first → check → custom build only when required) with decision checkpoints, though the bulk of design-guideline sections are unsequenced lists without explicit validation loops.	4 / 5
Progressive Disclosure	Twelve real, well-signaled one-level-deep reference files are listed up front and re-pointed to in context, but the large inlined 'UI/UX DESIGN SYSTEM' block reads like material that should itself be a separate reference, keeping it below a 5.	4 / 5
	Total	14 / 20 Passed

Description

58%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description clearly names the domain and its coverage areas in third person, but lacks an explicit 'when to use' trigger clause and natural user-facing trigger phrases. It is reasonably distinct but should add concrete trigger guidance to reach the top of the scale.

Suggestions

Add an explicit 'Use when...' clause naming concrete user triggers, e.g. 'Use when building or styling an Expo Router / React Native app, adding navigation, tabs, animations, or native UI controls.'

Include natural synonyms users would actually say (e.g. 'Expo app', 'React Native UI', 'mobile app') alongside 'Expo Router'.

Consider trimming the generic adjective 'beautiful' in favor of more concrete capability verbs.

Dimension	Reasoning	Score
Specificity	Names the Expo Router domain and lists several concrete coverage areas ('fundamentals, styling, components, navigation, animations, patterns, and native tabs'), with only minor gaps in action specificity.	4 / 5
Completeness	Has a clear 'what' (a guide for building apps with Expo Router) but provides no explicit 'Use when...' trigger clause, which caps completeness at 3 per the rubric.	3 / 5
Trigger Term Quality	Includes some relevant terms ('Expo Router', 'navigation', 'animations', 'tabs') but misses common natural phrasings users would say such as 'Expo app', 'React Native UI', or 'mobile app UI'.	3 / 5
Distinctiveness Conflict Risk	The 'Expo Router' anchor carves a fairly distinct niche with low overlap risk, though 'building beautiful apps' is broad enough to invite minor overlap with general UI skills.	4 / 5
	Total	14 / 20 Passed

Validation

93%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	15 / 16 Passed

Repository: Intelligent-Internet/ii-agent
Path: src/ii_agent/settings/skills/builtin/expo-building-ui/SKILL.md
Commit: 28563d6

Reviewed: 5 days ago

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