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muapi-youtube-thumbnail

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

56

Quality

64%

Does it follow best practices?

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SecuritybySnyk

Passed

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

Quality

Content

75%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 content is efficient and actionable, providing concrete muapi commands, a prompt template, and a fallback curl path within a clearly sequenced three-phase workflow. Main gaps are minor: no output verification checkpoint and the prompt/curl examples are template-assembled rather than copy-paste complete.

DimensionReasoningScore

Conciseness

The body is well-organized and mostly lean, with only minor over-explanation such as 'Thumbnails are the #1 factor in YouTube CTR' that could be trimmed; it largely assumes Claude's competence, matching 'efficient; minor instances of over-explanation'.

4 / 5

Actionability

It gives a concrete command ('muapi image generate' with model and aspect_ratio), a prompt-building template with placeholders, and a curl fallback endpoint, but the full prompt is assembled from templates rather than given as a single copy-paste example and the curl body uses a '{...}' placeholder, leaving minor gaps.

4 / 5

Workflow Clarity

Phases A, B, and C provide a clear sequence with substeps and an async-completion hint ('muapi predict wait'), but there is no explicit output validation/verification step, which is a minor gap rather than a disqualifying one since image generation is not destructive or batch.

4 / 5

Progressive Disclosure

The skill is self-contained with well-organized sections (Inputs, Steps, Notes, Trigger Keywords) and no bundle files; structure is good and navigation is easy, though it sits just over the simple-skill line and has no references to signal, matching 'good structure; minor organization gaps'.

4 / 5

Total

16

/

20

Passed

Description

53%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 is clear and on-niche but incomplete: it states what the skill does without any 'Use when...' trigger guidance, capping completeness, and it lacks synonyms for 'YouTube thumbnail'. Specificity is moderate because only a single design action is conveyed via attributes.

Suggestions

Add an explicit 'Use when...' clause naming concrete triggers, e.g. 'Use when the user asks for a YouTube/video thumbnail or cover image, or wants a high-CTR thumbnail design.'

Broaden trigger term coverage with synonyms like 'video thumbnail', 'yt thumbnail', and 'YouTube cover' so the description matches more natural phrasings.

Restate the action in third person (e.g. 'Designs a high-CTR YouTube thumbnail...') to align with the good-example voice and remove any ambiguity.

DimensionReasoningScore

Specificity

The description names the domain ('high-CTR YouTube thumbnail') and a few concrete attributes ('striking imagery, bold text placement, and emotional face/subject'), but it conveys a single design action rather than several distinct actions, so it stops at the '1-2 concrete actions' level rather than the multi-action level 4.

3 / 5

Completeness

It has a clear 'what' (design a high-CTR YouTube thumbnail) but no 'Use when...' clause or equivalent explicit trigger guidance, so per the rubric cap completeness cannot exceed 3.

3 / 5

Trigger Term Quality

It includes the natural phrase 'YouTube thumbnail' (and 'thumbnail'), which users do say, but omits common variations/synonyms such as 'video thumbnail', 'yt thumbnail', or 'YouTube cover', matching the 'some relevant keywords but missing variations' anchor.

3 / 5

Distinctiveness Conflict Risk

'High-CTR YouTube thumbnail' carves out a clear niche with minimal conflict risk, though it could still overlap with general image-generation skills, matching 'mostly distinct; minor overlap risk' rather than the fully-distinct 5.

4 / 5

Total

13

/

20

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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