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imagegen-frontend-mobile

Elite mobile app image-generation skill for creating premium, app-native screen concepts and flows. Designed for iOS, Android, and cross-platform mobile products. Prioritizes clean hierarchy, comfortably readable text, strong multi-screen consistency, controlled color palettes, non-generic creative direction, textured surfaces, image-led composition, tasteful custom iconography, and clean phone mockup framing. By default, screens should be shown inside a subtle premium iPhone or similar phone mockup with a visible frame, while the main focus stays on the app content itself. This skill generates images only. It does not write code.

49

Quality

62%

Does it follow best practices?

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SecuritybySnyk

Passed

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Fix and improve this skill with Tessl

tessl review fix ./skills/imagegen-frontend-mobile/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

48%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 body is well-sectioned and its art-direction intent is coherent, with a real workflow sequence and self-check culture (quality checklist plus regeneration triggers). Its main weaknesses are severe repetition that inflates token cost roughly fourfold, a high proportion of vibe-language over operational guidance, and a completely monolithic structure with no progressive disclosure into reference files. Consolidating duplicated rules and splitting the variation engine, category biases, and examples into references would raise every dimension.

Suggestions

Deduplicate the repeated directives (readability, mockup framing, consistency, anti-generic palette) into single canonical rules — sections 29/30/35/36/38 and 9/10/34/35 currently restate each other, which alone could cut the file by well over half.

Move the section 22 Style Variation Engine, section 33 Category-Specific Bias tables, and section 37 Example Interpretations into separate reference files (e.g., references/variation-engine.md, references/categories.md) linked from a lean overview.

Convert vibe directives ('feel premium', 'calm hierarchy') into operational criteria — e.g., concrete type-size floors, margin ratios, or per-screen checklists — so the guidance is executable rather than descriptive.

DimensionReasoningScore

Conciseness

The ~1460-line body is heavily padded with the same directives restated across many sections: text readability recurs in section 1, 29, 30, 35, 36, and 38; mockup framing rules repeat across sections 9, 10, 34, 35, 36, and 38; multi-screen consistency appears in sections 6, 7, 32, and 35. It does not explain external concepts Claude already knows, so it is not level 1, but the duplication could compress the file to roughly a quarter of its size — matching 'noticeably verbose; several unnecessary... padded sections'.

2 / 5

Actionability

There is genuinely concrete guidance — section 22's 'Choose exactly 4' signature components and 'Choose 1' theme/typography/palette menus, section 4's screen-count mapping ('5 screens → generate 5 screen images'), and section 21's named anti-tells ('Acme', 'NovaCore', 'purple-blue fintech gradients'). However, much of the instruction is abstract mood language ('feel premium', 'calm hierarchy', 'elegant restraint') without operational specifics, so it sits between 'some concrete guidance but incomplete' and 'mostly executable guidance'.

3 / 5

Workflow Clarity

Section 36 lays out a 28-step response sequence (infer category → infer platform → lock design bible → generate screens → refine), section 35 provides a 27-item quality checklist, and section 34 gives explicit regeneration triggers that function as a validate-and-retry feedback loop. This matches 'clear sequence with most checkpoints present'; not level 5 because many steps are high-level directives ('choose a strong visual direction') and the checklist is verification-by-vibe rather than explicit pass/fail checkpoints.

4 / 5

Progressive Disclosure

The file is a 40KB monolith with zero bundle files or external references, and several sections (the section 22 style variation engine, section 33 category biases, section 37 example interpretations) clearly belong in separate reference files. It is above level 2 because the 38 numbered sections with consistent headers give it real structure and navigability, but the lack of any reference split keeps it at 'some structure but could be better organized; content that should be separate is inline'.

3 / 5

Total

12

/

20

Passed

Description

61%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 communicates a focused niche (premium mobile app screen/flow image generation, no code) with a firm boundary statement, but it front-loads an adjective-heavy priorities list instead of actions and omits any explicit 'Use when...' trigger clause. Adding a concrete trigger clause and trimming the style priorities would move it to the top anchors.

Suggestions

Add an explicit 'Use when...' clause (e.g., 'Use when the user asks for mobile app mockups, app UI concepts, onboarding/auth flow visuals, or app screen sets') to satisfy the completeness cap.

Replace the 'Prioritizes...' priority list with 2-3 concrete actions (e.g., 'generates multi-screen app flow concepts, onboarding/auth/home/detail screens, and framed phone mockup compositions').

Include natural user variations such as 'app UI', 'app design', 'app screens', and platform terms users actually say to lift trigger term coverage to the top anchor.

DimensionReasoningScore

Specificity

Names the domain ('mobile app image-generation skill for creating premium, app-native screen concepts and flows') and one or two concrete actions ('generates images only. It does not write code.'), but the bulk is a priorities/values list ('Prioritizes clean hierarchy, comfortably readable text, strong multi-screen consistency...') rather than enumerated actions. Fits the anchor for naming the domain with 1-2 concrete actions; not level 4 because it does not list several specific actions.

3 / 5

Completeness

The 'what' is clear ('creating premium, app-native screen concepts and flows... generates images only'), but there is no 'Use when...' clause or equivalent explicit trigger guidance in the description ('Designed for iOS, Android, and cross-platform mobile products' only weakly implies when). Per the judging guideline, a missing 'Use when...' clause caps completeness at 3; not level 2 because the 'what' is specific and concrete.

3 / 5

Trigger Term Quality

Contains natural terms a user would say — 'mobile app', 'iOS', 'Android', 'screen concepts', 'flows', 'phone mockup' — giving good keyword coverage. Falls short of level 5 because common variations are missing ('app UI', 'app design', 'app screens', 'wireframe'), which keeps it from comprehensive synonym coverage.

4 / 5

Distinctiveness Conflict Risk

The explicit boundary ('This skill generates images only. It does not write code.') carves a mostly distinct niche (mobile app screen imagery) away from coding and website skills. Not level 5 because the description itself contains no distinct trigger phrases, leaving minor overlap risk with general image-generation and UI-design skills.

4 / 5

Total

14

/

20

Passed

Validation

87%

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

Validation — 14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

skill_md_line_count

SKILL.md is long (1491 lines); consider splitting into references/ and linking

Warning

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

14

/

16

Passed

Repository

nexu-io/open-design

Path

skills/imagegen-frontend-mobile/SKILL.md

Reviewed

Table of Contents

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