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netlify-image-cdn

Transform, resize, crop, reformat, and optimize images on demand via Netlify Image CDN's /.netlify/images endpoint. Use when adding responsive images, generating thumbnails, converting formats (avif/webp/png), cropping to aspect ratios, tuning image quality, creating blurred placeholders, allowlisting remote image domains, serving user-uploaded images, or wiring framework image components (Next.js, Astro, Nuxt, Angular, Gatsby) to Netlify. Triggers on tasks like "optimize images", "add image thumbnails", "resize images on the fly", "serve images from an external domain", or "add blur placeholders".

74

Quality

91%

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SecuritybySnyk

Passed

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SKILL.md
Quality
Evals
Security

Quality

Content

82%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 well-structured, highly actionable reference skill with executable examples and clear sectioning, plus a properly signaled one-level-deep reference file. Its main weakness is redundancy between the main body and the appended house-rules section, which inflates the token budget.

Suggestions

Remove the duplicated 'Netlify house rules' section (lines 135-160) or reduce it to a one-line pointer — its guidance (percent-encoding, blurhash text, local 404, regex escape) is already covered in the body, and the duplication hurts conciseness.

Consolidate the percent-encoding and regex-escape guidance into a single 'Remote source gotchas' callout so the same advice isn't restated in two places.

If the house-rules block is required by the ctx-gen merge process, mark it explicitly as machine-managed so a reader knows it intentionally mirrors the body and can skip it.

DimensionReasoningScore

Conciseness

The body is dense and token-efficient — tables for params/fit/frameworks, no padded explanations of what images or CDNs are — but the appended 'Netlify house rules' section (lines 135-160) duplicates guidance already in the body (percent-encoding, blurhash text, local 404, regex dot-escape), so it is not fully lean.

4 / 5

Actionability

It provides copy-paste-ready, executable examples across the common cases — a working curl request, netlify.toml remote_images, encodeURIComponent JS, _redirects and _headers snippets — covering the actual operations a user needs.

5 / 5

Workflow Clarity

Sections are clearly organized by task (endpoint params, remote sources, redirects, headers, frameworks, local dev) with a useful diagnostic feedback loop for the local-404 case, but there is no explicit multi-step validated workflow since this is a reference-style skill rather than a destructive/batch process.

4 / 5

Progressive Disclosure

The body is well-sectioned and points the user-uploads pipeline to references/user-uploads.md, a verified one-level-deep file with no nested references; the bulk reference content is mostly appropriately placed, with only minor organization gaps.

4 / 5

Total

17

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20

Passed

Description

100%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 concretely states capabilities, gives explicit 'Use when' and 'Triggers on' guidance, and is tightly scoped to the Netlify Image CDN domain. No fluff or over-claims.

DimensionReasoningScore

Specificity

The description lists multiple concrete actions — 'Transform, resize, crop, reformat, and optimize images on demand' — plus wiring framework image components, giving comprehensive coverage of the skill's capabilities.

5 / 5

Completeness

It explicitly answers both 'what' (the listed transformation actions) and 'when' via an explicit 'Use when adding responsive images...' clause and a 'Triggers on tasks like...' list with concrete trigger phrases.

5 / 5

Trigger Term Quality

It includes natural phrases users would actually say ('optimize images', 'add image thumbnails', 'resize images on the fly', 'add blur placeholders') alongside format synonyms (avif/webp/png), giving comprehensive natural-term coverage.

5 / 5

Distinctiveness Conflict Risk

The Netlify Image CDN niche is clearly scoped with distinct triggers ('/.netlify/images endpoint', framework wiring) and minimal overlap risk with unrelated skills.

5 / 5

Total

20

/

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.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
netlify/context-and-tools
Reviewed

Table of Contents

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