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-meta-oggit 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-meta-og)<a href="https://agentmods.dev/skills/dragoon0x/canon/canon-meta-og"><img src="https://agentmods.dev/badge/skills/dragoon0x/canon/canon-meta-og/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-meta-og"><img src="https://agentmods.dev/badge/skills/dragoon0x/canon/canon-meta-og.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 | $0.00064 | $0.00782 |
| Opus 5 | $0.00032 | $0.00391 |
| Sonnet 5 | $0.00013 | $0.00156 |
| Haiku 4.5 | $0.00006 | $0.00078 |
Grade A, and why
canon-meta-og 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 — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CANON · Meta / Open Graph
When someone shares your URL on Slack, Twitter, LinkedIn, iMessage, or WhatsApp, these tags control what they see. Without them, the preview is a bare URL or a random scraped snippet.
Essential Open Graph tags
<meta property="og:title" content="Page Title">
<meta property="og:description" content="Concise summary of the page.">
<meta property="og:image" content="https://example.com/og-image.png">
<meta property="og:url" content="https://example.com/page">
<meta property="og:type" content="website">
<meta property="og:site_name" content="Site Name">
Twitter Card tags
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:title" content="Page Title">
<meta name="twitter:description" content="Concise summary.">
<meta name="twitter:image" content="https://example.com/og-image.png">
summary_large_image shows a large preview. summary shows a small thumbnail. Large image gets more clicks.
OG image spec
| Property | Value |
|---|---|
| Recommended size | 1200×630px |
| Minimum size | 600×315px |
| Format | PNG or JPEG (PNG for text-heavy, JPEG for photos) |
| File size | ≤ 1MB (smaller is better for fast preview) |
| Text safety zone | Keep text 60px from edges (platforms crop differently) |
Every page should have a unique og:image. Fallback to a site-wide default if page-specific isn't available.
Dynamic OG images
For pages with user-generated content (blog posts, profiles), generate OG images dynamically:
https://example.com/api/og?title=My+Post&author=Deep
Use @vercel/og, Satori, or Puppeteer to render HTML → image server-side.
Validation tools
- Facebook:
https://developers.facebook.com/tools/debug/ - Twitter:
https://cards-dev.twitter.com/validator - LinkedIn:
https://www.linkedin.com/post-inspector/ - Open Graph debugger:
https://www.opengraph.xyz/
Test after every change — platforms cache aggressively.
Anti-patterns
| Anti-pattern | Why it fails |
|---|---|
| No og:image | Preview is text-only, low engagement |
| Same og:image for every page | Every share looks identical |
| og:image with text cut off at edges | Platforms crop differently |
| og:title longer than 60 characters | Truncated in most previews |
| HTTP (not HTTPS) og:image URL | Some platforms reject it |
| Missing og:url (or wrong URL) | Canonical confusion |
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 · 89 lines · 64 tokens per session scan A ba5a2317b04b
canon-meta-og is a skill published in the GitHub repository Dragoon0x/canon (6 stars, last pushed 4mo ago), licensed MIT. It adds 64 tokens to every session and 782 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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