Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add aj-geddes/useful-ai-prompts --skill image-optimizationgit clone --depth 1 https://github.com/aj-geddes/useful-ai-promptsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/image-optimization)<a href="https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/image-optimization"><img src="https://agentmods.dev/badge/skills/aj-geddes/useful-ai-prompts/image-optimization/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/image-optimization"><img src="https://agentmods.dev/badge/skills/aj-geddes/useful-ai-prompts/image-optimization.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00029 | $0.00509 |
| Opus 5 | $0.00015 | $0.00254 |
| Sonnet 5 | $0.00006 | $0.00102 |
| Haiku 4.5 | $0.00003 | $0.00051 |
Grade A, and why
image-optimization scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Image Optimization
Table of Contents
Overview
Images typically comprise 50% of page weight. Optimization dramatically improves performance, especially on mobile networks.
When to Use
- Website optimization
- Responsive image implementation
- Performance improvement
- Mobile experience enhancement
- Before deployment
Quick Start
Minimal working example:
Format Selection:
JPEG:
Best for: Photographs, complex images
Compression: Lossy (quality 70-85)
Size: ~50-70% reduction
Tools: ImageMagick, TinyJPEG
Command: convert image.jpg -quality 75 optimized.jpg
PNG:
Best for: Icons, screenshots, transparent images
Compression: Lossless
Size: 10-30% reduction
Tools: PNGQuant, OptiPNG
Command: optipng -o3 image.png
WebP:
Best for: Modern browsers (90% support)
Compression: 25-35% better than JPEG/PNG
Fallback: Use <picture> element
Tools: cwebp
Command: cwebp -q 75 image.jpg -o image.webp
SVG:
Best for: Icons, logos, simple graphics
// ... (see reference guides for full implementation)
Reference Guides
Detailed implementations in the references/ directory:
| Guide | Contents |
|---|---|
| Image Compression & Formats | Image Compression & Formats |
| Responsive Images | Responsive Images |
| Optimization Process | Optimization Process |
| Monitoring & Best Practices | Monitoring & Best Practices |
Best Practices
✅ DO
- Follow established patterns and conventions
- Write clean, maintainable code
- Add appropriate documentation
- Test thoroughly before deploying
❌ DON'T
- Skip testing or validation
- Ignore error handling
- Hard-code configuration values
What ships with it
5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 9d ago First seen · 88 lines · 29 tokens per session scan A a72cbae0393e
image-optimization is a skill published in the GitHub repository aj-geddes/useful-ai-prompts (338 stars, last pushed 6mo ago), licensed MIT. It adds 29 tokens to every session and 509 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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