CtrlK
BlogDocsLog inGet started
Tessl Logo

x-image-cards

Create X/Twitter cards that look like images, not marketing banners. Use when asked to "create OG images", "set up X cards", "make social cards", or "twitter card without text".

93

1.78x

Quality

95%

Does it follow best practices?

Impact

91%

1.78x

Average score across 6 eval scenarios

SecuritybySnyk

Passed

No known issues

SKILL.md
Quality
Evals
Security

X Image Cards

Create X cards that look like images, not marketing banners. Let the visual be the content — X already shows your title and description in the card UI.

X-Specific Requirements

SpecValueWhy
Dimensions2400×1200 physical (1200×600 logical)2x for retina, 2:1 aspect ratio
Safe margins50-56px padding (at 1x)X clips edges on mobile
URL format/og/page.png not /og/page?format=pngX prefers explicit extensions
Colors#FFFFFF primary, avoid subtle graysThumbnails are tiny

Zero-Width Space Trick

X overlays og:title as white text on the image. Hide it with a zero-width space:

<meta property="og:title" content="&#8203;" />

In JSX: content={"\u200B"}

Your page <title> stays descriptive for SEO — only og:title uses the trick.

Meta Tags

<meta property="og:image" content="https://example.com/og/page.png" />
<meta property="og:image:width" content="1200" />
<meta property="og:image:height" content="600" />
<meta property="og:title" content="&#8203;" />
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:image" content="https://example.com/og/page.png" />

Dynamic Generation

Use @vercel/og with 2x scale and safe margins:

import { ImageResponse } from '@vercel/og';

const OG_SCALE = 2;

export async function GET(request: Request) {
  return new ImageResponse(
    (
      <div style={{
        width: '100%',
        height: '100%',
        display: 'flex',
        backgroundColor: '#0a0f1c',
        padding: 100, // 50px * 2 for safe margins
      }}>
        {/* Your visual content here */}
      </div>
    ),
    { width: 1200 * OG_SCALE, height: 600 * OG_SCALE }
  );
}

Express

app.get('/og/:slug.png', async (req, res) => {
  const image = new ImageResponse(/* ... */);
  const buffer = await image.arrayBuffer();

  res.setHeader('Content-Type', 'image/png');
  res.setHeader('Cache-Control', 'public, max-age=86400');
  res.send(Buffer.from(buffer));
});

Dynamic Routes (Optional)

For per-page OG images, two approaches:

On-Demand Generation

Generate when crawler requests the image:

/og/[slug].png  →  generates image on request

Risk: X crawlers timeout after ~5 seconds. Cold starts can exceed this, causing blank previews.

Pre-Generated (Recommended)

Generate and store image when content is created:

// On content creation
const imageBuffer = await generateOgImage(data);
await db.insert({ ogImageData: imageBuffer }); // Store as BYTEA

// On request - instant response
app.get('/og/:id.png', (req, res) => {
  const { ogImageData } = await db.get(req.params.id);
  res.setHeader('Content-Type', 'image/png');
  res.send(ogImageData);
});

Pre-generation ensures instant response for crawlers.

Checklist

  • 2400×1200 (2x retina)
  • 2:1 aspect ratio
  • 50-56px safe margins
  • High contrast colors
  • .png extension in URL
  • Zero-width space in og:title
  • Test: https://cards-dev.twitter.com/validator

Built for BondTerminal. See it in action: example X post.

Repository
NeverSight/skills_feed
Last updated
Created

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.