What is canon-meta-og?

A guide for metadata that controls how a web page appears when its link is shared. Open Graph and Twitter Card tags provide the title, description, image, URL, and page type shown in previews on services such as Slack, LinkedIn, and WhatsApp.

Use it to add and review social-sharing tags and choose suitable preview image dimensions, format, and card style.

It prevents shared links from showing a bare URL, random text, or an unsuitable image.

canon-meta-og — Skill for Claude Code and Codex by Dragoon0x/canon

Install

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.

Any agent

npx skills add Dragoon0x/canon --skill canon-meta-og

Clone the repo

git clone --depth 1 https://github.com/Dragoon0x/canon

Made for: Claude Code, Codex.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/dragoon0x/canon/canon-meta-og/github.svg)](https://agentmods.dev/skills/dragoon0x/canon/canon-meta-og)

Your own site

<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.

Your own site · 80×15

<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>

Per session 64 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 782 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

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 5.5	$0.00026	$0.00313
Sonnet 5.5	$0.00013	$0.00156
Haiku 4.5	$0.00006	$0.00078

Measured 2mo ago against content hash ba5a2317b04b, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

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 2mo 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.

source/skills/canon-meta-og/SKILL.md · 89 lines

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

Read the full file on GitHub · 89 lines

Changes

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.

2mo ago First seen · 89 lines · 64 tokens per session scan A ba5a2317b04b

Subscribe to this mod's changes

canon-meta-og is a skill published in the GitHub repository Dragoon0x/canon (6 stars, last pushed 6mo ago), licensed MIT. It adds 64 tokens to every session and 782 once invoked, about $0.0003 per session on Opus 5.5. 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.

Claude Code Marketing and SEO accessibility ai-agent ai-coding audit codex

canon-meta-og next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
canon-meta-ogDragoon0x/canon	Skill	6	6mo ago	MIT	A	64	Claude Code, Codex
accessibilitydiegosouzapw/awesome-omni-skills	Skill	170	4mo ago	MIT	C	119	Claude Code, Codex
accessibilityericrisco/rsc-harness	Skill	503	2d ago	MIT	A	86	Claude Code, Codex
Website AuditPramodDutta/qaskills	Skill	245	4d ago	MIT	A	33	Claude Code, Codex
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accessibility-auditoyi77/1ai-skills	Skill	17	yesterday	MIT	A	29	Claude Code
a11y-auditgreglas75/zuvo	Skill	7	3d ago	MIT	A	147	Claude Code