---
name: seo-images-ef5b4440fa0e
description: >
Image optimization analysis for SEO and performance. Checks alt text, file
sizes, formats, responsive images, lazy loading, and CLS prevention. Use when
user says "image optimization", "alt text", "image SEO", "image size",
or "image audit".
user-invokable: true
argument-hint: "[url]"
allowed-tools:
- web_open
- web_read_text
- web_read_html
- web_seo_audit
- web_exec_js
- web_click
- web_type_input
- web_press_key
- term_run_command
---
# Image Optimization Analysis
## Checks
### Alt Text
- Present on all `` elements (except decorative: `role="presentation"`)
- Descriptive: describes the image content, not "image.jpg" or "photo"
- Includes relevant keywords where natural, not keyword-stuffed
- Length: 10-125 characters
**Good examples:**
- "Professional plumber repairing kitchen sink faucet"
- "Red 2024 Toyota Camry sedan front view"
- "Team meeting in modern office conference room"
**Bad examples:**
- "image.jpg" (filename, not description)
- "plumber plumbing plumber services" (keyword stuffing)
- "Click here" (not descriptive)
### File Size
**Tiered thresholds by image category:**
| Image Category | Target | Warning | Critical |
|----------------|--------|---------|----------|
| Thumbnails | < 50KB | > 100KB | > 200KB |
| Content images | < 100KB | > 200KB | > 500KB |
| Hero/banner images | < 200KB | > 300KB | > 700KB |
Recommend compression to target thresholds where possible without quality loss.
### Format
| Format | Browser Support | Use Case |
|--------|-----------------|----------|
| WebP | 97%+ | Default recommendation |
| AVIF | 92%+ | Best compression, newer |
| JPEG | 100% | Fallback for photos |
| PNG | 100% | Graphics with transparency |
| SVG | 100% | Icons, logos, illustrations |
Recommend WebP/AVIF over JPEG/PNG. Check for `` element with format fallbacks.
#### Recommended `` Element Pattern
Use progressive enhancement with the most efficient format first:
```html
```
The browser will use the first supported format. Current browser support: AVIF 93.8%, WebP 95.3%.
#### JPEG XL: Emerging Format
In November 2025, Google's Chromium team reversed its 2022 decision and announced it will restore JPEG XL support in Chrome using a Rust-based decoder. The implementation is feature-complete but not yet in Chrome stable. JPEG XL offers lossless JPEG recompression (~20% savings with zero quality loss) and competitive lossy compression. Not yet practical for web deployment, but worth monitoring for future adoption.
### Responsive Images
- `srcset` attribute for multiple sizes
- `sizes` attribute matching layout breakpoints
- Appropriate resolution for device pixel ratios
```html
```
### Lazy Loading
- `loading="lazy"` on below-fold images
- Do NOT lazy-load above-fold/hero images (hurts LCP)
- Check for native vs JavaScript-based lazy loading
```html
```
### `fetchpriority="high"` for LCP Images
Add `fetchpriority="high"` to your hero/LCP image to prioritize its download in the browser's network queue:
```html
```
**Critical:** Do NOT lazy-load above-the-fold/LCP images. Using `loading="lazy"` on LCP images directly harms LCP scores. Reserve `loading="lazy"` for below-the-fold images only.
### `decoding="async"` for Non-LCP Images
Add `decoding="async"` to non-LCP images to prevent image decoding from blocking the main thread:
```html
```
### CLS Prevention
- `width` and `height` attributes set on all `` elements
- `aspect-ratio` CSS as alternative
- Flag images without dimensions
```html
```
### File Names
- Descriptive: `blue-running-shoes.webp` not `IMG_1234.jpg`
- Hyphenated, lowercase, no special characters
- Include relevant keywords
### CDN Usage
- Check if images served from CDN (different domain, CDN headers)
- Recommend CDN for image-heavy sites
- Check for edge caching headers
## Output
### Image Audit Summary
| Metric | Status | Count |
|--------|--------|-------|
| Total Images | - | XX |
| Missing Alt Text | ❌ | XX |
| Oversized (>200KB) | ⚠️ | XX |
| Wrong Format | ⚠️ | XX |
| No Dimensions | ⚠️ | XX |
| Not Lazy Loaded | ⚠️ | XX |
### Prioritized Optimization List
Sorted by file size impact (largest savings first):
| Image | Current Size | Format | Issues | Est. Savings |
|-------|--------------|--------|--------|--------------|
| ... | ... | ... | ... | ... |
### Recommendations
1. Convert X images to WebP format (est. XX KB savings)
2. Add alt text to X images
3. Add dimensions to X images
4. Enable lazy loading on X below-fold images
5. Compress X oversized images
## Error Handling
| Scenario | Action |
|----------|--------|
| URL unreachable | Report connection error with status code. Suggest verifying URL and checking if site requires authentication. |
| No images found on page | Report that no `` elements were detected. Suggest checking if images are loaded via JavaScript or CSS background-image. |
| Images behind CDN or authentication | Note that image files could not be directly accessed for size analysis. Report available metadata (alt text, dimensions, format from markup) and flag inaccessible resources. |
---
Source attribution: mits-pl
Original project: https://github.com/mits-pl/wove/blob/8a3ba437a292b434ff64ec8b09ef876090385fc7/.claude/skills/seo-images/SKILL.md
License: Apache-2.0
License information: https://www.apache.org/licenses/LICENSE-2.0
Original upstream instructions; downloaded from Dave AI.
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## Additional upstream notices
seo-images-ef5b4440fa0e/DAVEAI-UPSTREAM-NOTICE
Wove
Copyright 2025-2026 MITS Sp. z o.o.
Built on Wave Terminal
Copyright 2025 Command Line Inc.
Licensed under Apache License 2.0
https://github.com/wavetermdev/waveterm
# Dave AI resource metadata
Creator / publisher: mits-pl
Original project: https://github.com/mits-pl/wove/blob/8a3ba437a292b434ff64ec8b09ef876090385fc7/.claude/skills/seo-images/SKILL.md
Attribution basis: Source repository record
Fields of work: Marketing
Roles: Content Marketer, Marketing Analyst, SEO Specialist
Specialties: Specialty not specified
Tools: Term_Run_Command, Web_Click, Web_Exec_Js, Web_Open, Web_Press_Key, Web_Read_Html, Web_Read_Text, Web_Seo_Audit, Web_Type_Input
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: df22d02e46508e0903b83fcc963ccf9a8550d0efb057265826e7441119130ba1
```
### Lazy Loading
- `loading="lazy"` on below-fold images
- Do NOT lazy-load above-fold/hero images (hurts LCP)
- Check for native vs JavaScript-based lazy loading
```html