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 Dragoon0x/canon --skill canon-faviconsgit clone --depth 1 https://github.com/Dragoon0x/canonWrote 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/dragoon0x/canon/canon-favicons)<a href="https://agentmods.dev/skills/dragoon0x/canon/canon-favicons"><img src="https://agentmods.dev/badge/skills/dragoon0x/canon/canon-favicons/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/dragoon0x/canon/canon-favicons"><img src="https://agentmods.dev/badge/skills/dragoon0x/canon/canon-favicons.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00068 | $0.00937 |
| Opus 5 | $0.00034 | $0.00468 |
| Sonnet 5 | $0.00014 | $0.00187 |
| Haiku 4.5 | $0.00007 | $0.00094 |
Grade A, and why
canon-favicons 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 99 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CANON · Favicons
Favicons are the smallest piece of branding and the most often botched. Modern browsers need multiple sizes, formats, and declarations.
The minimal set
<link rel="icon" href="/favicon.ico" sizes="32x32">
<link rel="icon" href="/icon.svg" type="image/svg+xml">
<link rel="apple-touch-icon" href="/apple-touch-icon.png">
<link rel="manifest" href="/manifest.webmanifest">
Files to generate
| File | Size | Format | Purpose |
|---|---|---|---|
favicon.ico |
32×32 (can embed 16×16) | ICO | Legacy browsers, bookmarks bar |
icon.svg |
Scalable | SVG | Modern browsers (Chrome, Firefox) |
apple-touch-icon.png |
180×180 | PNG | iOS home screen |
icon-192.png |
192×192 | PNG | Android home screen, PWA |
icon-512.png |
512×512 | PNG | PWA splash screen |
SVG favicon with dark mode
SVG favicons can adapt to dark mode:
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 32 32">
<style>
rect { fill: #0a0a0a; }
@media (prefers-color-scheme: dark) {
rect { fill: #f5f5f5; }
}
</style>
<rect width="32" height="32" rx="4"/>
</svg>
Web app manifest
{
"name": "My App",
"short_name": "App",
"icons": [
{ "src": "/icon-192.png", "sizes": "192x192", "type": "image/png" },
{ "src": "/icon-512.png", "sizes": "512x512", "type": "image/png" }
],
"theme_color": "#0a0a0a",
"background_color": "#ffffff",
"display": "standalone"
}
theme_color affects the browser toolbar color on Android.
Design rules
- Simple at 16px. If your logo doesn't read at 16×16, simplify it to a lettermark or geometric shape.
- No text at small sizes. Text is illegible below 32px.
- High contrast against both light and dark browser chrome. Test on light and dark OS themes.
- Square. All favicon slots are square. Don't force a horizontal logo into a square; make a square variant.
- No transparency for apple-touch-icon. iOS fills transparent areas with black. Use a solid background.
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.
- 12d ago First seen · 99 lines · 68 tokens per session scan A 7ecee5cfb1cd
canon-favicons is a skill published in the GitHub repository Dragoon0x/canon (6 stars, last pushed 4mo ago), licensed MIT. It adds 68 tokens to every session and 937 once invoked, about $0.0003 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 2026-08-31.
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