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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.

48

Quality

52%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

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

Quality

Content

47%

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

The skill is well-structured with a clear response workflow, checklist, and refinement loop, but it is severely over-long and repetitive for an instruction-only image-gen skill, with no progressive disclosure to offload the bulk. Actionability is mixed: a strong enumerated variation engine sits inside a lot of abstract feel-language.

Suggestions

Collapse the redundant sections (text readability appears in 28/29/30/35, phone mockup in 9/10/35/37, no-code in the directive/103-107/1385) into single canonical statements to cut length dramatically and raise conciseness.

Move the Style Variation Engine (Section 22), Category-Specific Bias (Section 33), and baseline config (Section 1) into separate reference files referenced one level deep from SKILL.md to improve progressive disclosure.

Replace abstract feel-directives ("feel premium", "be calm") with specific, checkable criteria so the guidance is more directly actionable.

DimensionReasoningScore

Conciseness

The ~1460-line body is highly verbose and repetitive: the text-readability, phone-mockup, no-code, and anti-AI-tells directives each recur across multiple of the 38 sections, padded with feel-words ("premium", "calm", "believable") that restate mobile-design intuition Claude already has.

1 / 3

Actionability

It offers concrete levers (the Style Variation Engine with "Choose exactly 4", numeric baseline config, explicit screen-count rules) but interleaves them with abstract direction ("feel premium", "be calm", "make it memorable") that is not directly executable.

2 / 3

Workflow Clarity

Section 36 lays out a 28-step response sequence, Section 35 provides a 27-item quality checklist, and Section 34 defines a regenerate feedback loop — a clear sequence with checkpoints and an error-recovery loop matching the top anchor.

3 / 3

Progressive Disclosure

The body is well-sectioned into 38 numbered headers, but it is a monolithic single file with no bundle/reference files; large reusable blocks (the variation engine, category biases, baseline config) that should be split out are all inlined.

2 / 3

Total

8

/

12

Passed

Description

57%

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 conveys a clear, distinctive niche (mobile app image concepts, image-only, no code) but is weighed down by buzzword padding and lacks an explicit "Use when..." trigger clause in the description text itself. Trigger coverage is decent but the strongest triggers are sequestered in a separate frontmatter field.

Suggestions

Add an explicit "Use when..." clause to the description naming the situations that should activate this skill (e.g., mobile app mockups, onboarding/auth flow concepts, multi-screen app concepts).

Trim marketing adjectives ("Elite", repeated "premium") and replace feel-words with a few more concrete capabilities to lift specificity from 2 to 3.

Fold the most natural trigger phrases ("mobile app mockup", "app UI concept", "ios/android app design") directly into the description so trigger-term quality does not depend on a separate field.

DimensionReasoningScore

Specificity

Names the domain and a concrete core action ("creating premium, app-native screen concepts and flows") but pads the rest with buzzword-heavy qualities ("Elite", "premium" repeated) rather than enumerating multiple distinct actions, so it stops short of comprehensive.

2 / 3

Completeness

It clearly answers "what" the skill does, but lacks an explicit "Use when..." clause or equivalent trigger guidance in the description, which per the rubric caps completeness at 2; the "when" is only implied via the mobile domain framing.

2 / 3

Trigger Term Quality

The description contains some natural terms ("mobile app", "screen concepts", "iOS", "Android", "phone mockup") but misses common variations like "app design" or "mockup concept"; the strongest trigger terms actually live in a separate frontmatter `triggers` field rather than the description itself.

2 / 3

Distinctiveness Conflict Risk

It carves a clear niche — mobile-only image generation explicitly scoped as "generates images only. It does not write code" — making it unlikely to trigger for web, desktop, or code skills.

3 / 3

Total

9

/

12

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.

Validation14 / 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
Reviewed

Table of Contents

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