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muapi-youtube-thumbnail

Design a high-CTR YouTube thumbnail — striking imagery, bold text placement, and emotional face/subject if needed.

60

Quality

71%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./.opencode/skills/muapi-youtube-thumbnail/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

85%

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-structured and highly actionable with concrete commands and a clear three-phase workflow, and it appropriately stays self-contained without unnecessary bundle references. The only notable ding is minor redundancy from restating the description and a light padding line.

DimensionReasoningScore

Conciseness

The body is largely lean and assumes Claude's competence, but it redundantly restates the full frontmatter description in bold ('Design a high-CTR YouTube thumbnail — striking imagery, bold text placement, and emotional face/subject if needed.') and opens with the unneeded claim 'Thumbnails are the #1 factor in YouTube CTR.', which keeps it just shy of the anchor-3 'every token earns its place.'

2 / 3

Actionability

Guidance is concrete and executable: a specific command 'Call muapi image generate (model=gpt-image-2-text-to-image, aspect_ratio=16:9)', explicit style-tag strings with {{placeholders}}, and a copy-paste-ready curl fallback with polling via 'muapi predict wait <request_id>'.

3 / 3

Workflow Clarity

The process is clearly sequenced into Phase A (plan), Phase B (generate), Phase C (text overlay); as a simple single-purpose image-generation skill it involves no destructive or batch operations that would require validation feedback loops, so the scoring_notes.simple_skills allowance applies.

3 / 3

Progressive Disclosure

No bundle files exist (references/scripts/assets absent) and none are needed; the single self-contained file is well organized into Inputs, Steps, Notes, Trigger Keywords, and Notes for the Executing Agent, satisfying the well-organized-sections criterion for skills with no external references.

3 / 3

Total

11

/

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 clearly conveys what the skill does and occupies a distinct niche, but it lacks an explicit 'Use when' trigger clause and broader keyword coverage. Adding a trigger clause with natural term variations would lift completeness and trigger_term_quality.

Suggestions

Append an explicit 'Use when...' clause, e.g. 'Use when the user asks for a YouTube/yt thumbnail or video cover image.'

Expand trigger terms in the description to include natural variations like 'yt thumbnail', 'video thumbnail', and 'youtube cover'.

Lead with concrete verbs (e.g. 'Generate and art-direct a 16:9 thumbnail image with...') to strengthen specificity.

DimensionReasoningScore

Specificity

Quotes 'Design a high-CTR YouTube thumbnail — striking imagery, bold text placement, and emotional face/subject if needed' name the domain and several design elements, but stop short of a comprehensive list of concrete actions like the anchor-3 example ('extract, fill, merge').

2 / 3

Completeness

The 'what' is clearly stated ('Design a high-CTR YouTube thumbnail...'), but there is no explicit 'Use when...' trigger clause, so per the judging guidelines completeness is capped at 2.

2 / 3

Trigger Term Quality

'YouTube thumbnail' is a natural term a user would say, but the description omits common variations (yt thumbnail, video cover, thumbnail) that appear only in the body's Trigger Keywords section, matching the anchor-2 'some relevant keywords but missing common variations.'

2 / 3

Distinctiveness Conflict Risk

'YouTube thumbnail' carves out a clear, narrow niche that is unlikely to overlap with or mistakenly trigger other skills.

3 / 3

Total

9

/

12

Passed

Validation

93%

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

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

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

Warning

Total

15

/

16

Passed

Repository
SamurAIGPT/Generative-Media-Skills
Reviewed

Table of Contents

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