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image-optimization

Optimizes images for web performance using modern formats, responsive techniques, and lazy loading strategies. Use when improving page load times, implementing responsive images, or preparing assets for production deployment.

86

1.36x
Quality

80%

Does it follow best practices?

Impact

98%

1.36x

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./plugins/image-optimization/skills/image-optimization/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

72%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.

A concise, actionable reference for image optimization with executable code and concrete targets, but it presents techniques as a flat catalog rather than a sequenced workflow with validation checkpoints for batch processing.

Suggestions

Add an explicit ordered workflow (e.g., audit -> choose format -> generate responsive variants -> compress -> verify size targets) with a validation step that confirms output KB targets are met before deployment.

Expand the Sharp build pipeline to show AVIF generation and srcset variant production, since these are common cases only hinted at by the format table.

Remove or repurpose the redundant opening sentence that restates the frontmatter description.

DimensionReasoningScore

Conciseness

Mostly lean with tables and clean code examples, but the opening line ('Optimize images for web performance with modern formats and responsive techniques') redundantly restates the description and could be trimmed.

4 / 5

Actionability

Provides copy-paste-ready HTML and Sharp snippets plus concrete KB targets and a checklist, but the Sharp example only covers WebP output and omits programmatic srcset/AVIF generation for other common cases.

4 / 5

Workflow Clarity

Content is organized as parallel reference sections with a loose checklist rather than a sequenced workflow, and lacks validation/verification checkpoints for what is effectively a batch image operation, capping this dimension at 3.

3 / 5

Progressive Disclosure

A compact, single-purpose skill with no bundle files and well-organized section headers; per the simple-skkill guidance, well-organized sections alone earn a 5 when no external references are needed.

5 / 5

Total

16

/

20

Passed

Description

87%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.

A strong, third-person description that clearly states capabilities and provides explicit 'Use when' trigger guidance with natural keywords. Minor improvement possible by adding file-extension synonyms and a few more distinct concrete actions.

DimensionReasoningScore

Specificity

Names the domain and lists several specific technique areas ('modern formats, responsive techniques, and lazy loading strategies'), with only minor gaps in coverage compared to the comprehensive five-action anchor.

4 / 5

Completeness

Explicitly answers both what ('Optimizes images for web performance using modern formats, responsive techniques, and lazy loading strategies') and when ('Use when improving page load times, implementing responsive images, or preparing assets for production deployment') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Good natural keyword coverage ('page load times', 'responsive images', 'production deployment'), but missing common synonyms or file extensions like '.jpg', '.png', or 'compress images'.

4 / 5

Distinctiveness Conflict Risk

Image optimization is a clear niche with distinct triggers tied to page load and responsive imagery, giving minimal conflict risk with other skills.

5 / 5

Total

18

/

20

Passed

Validation

100%

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

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
secondsky/claude-skills
Reviewed

Table of Contents

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