Image Creator

When to use

Use the Visual Renderer when you need to generate production-ready images from HTML/CSS. This skill uses Playwright to render complete, self-contained HTML files in a headless browser and capture pixel-perfect screenshots. It is the primary engine for creating social media graphics, carousel slides, infographics, and any other visual content defined by HTML templates.

Instructions

Core Workflow

Generate HTML -- Write a complete, self-contained HTML file with inline CSS. The HTML IS the design -- all styling, layout, fonts, colors, and content must be embedded.
Save HTML -- Write the HTML file to the squad's output folder (e.g., output/slides/slide-01.html)
Start HTTP server -- Before rendering, start a local HTTP server in the squad's output folder:
```
python -m http.server 8765 --directory "OUTPUT_DIR" &
for i in $(seq 1 30); do curl -s http://localhost:8765 > /dev/null 2>&1 && break || sleep 0.1; done
```
Replace OUTPUT_DIR with the actual absolute path to the output folder (quote paths that contain spaces).
Render -- Use Playwright to:
- browser_navigate to http://localhost:8765/slide-01.html (filename only, not full path)
- browser_resize to target viewport dimensions
- browser_take_screenshot to save as PNG
Verify -- Read the screenshot to confirm quality. Re-render if needed.
Stop server -- After all slides are rendered, stop the HTTP server:
```
pkill -f "http.server 8765" 2>/dev/null || true
```

Viewport Presets (width x height)

Use these standard dimensions:

Instagram Post: 1080 x 1080
Instagram Carousel: 1080 x 1440
Instagram Story/Reel: 1080 x 1920
Facebook Post: 1200 x 630
Twitter/X Post: 1200 x 675
LinkedIn Post: 1200 x 627
YouTube Thumbnail: 1280 x 720
Custom: as specified by the squad

HTML Template Guidelines

The HTML you generate MUST:

Be self-contained (inline CSS, no external dependencies)
Use web-safe fonts OR Google Fonts via @import
Embed images as absolute paths or base64 data URIs
Set exact body dimensions matching the viewport
Use margin: 0; padding: 0; overflow: hidden on body
Account for device pixel ratio if high-res needed

Example minimal structure:

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <style>
    * { margin: 0; padding: 0; box-sizing: border-box; }
    body { width: 1080px; height: 1440px; overflow: hidden; }
    /* ... your design ... */
  </style>
</head>
<body>
  <!-- Your content -->
</body>
</html>

Batch Rendering (Carousels/Multi-slide)

For multi-image outputs like carousels:

Generate one HTML file per slide
Start the HTTP server once before the batch (step 3 of Core Workflow)
Render each slide sequentially (step 4 repeated per slide)
Stop the HTTP server once after all slides are done (step 6 of Core Workflow)
Name output files with zero-padded numbers: slide-01.png, slide-02.png, slide-03.png
Keep all slides at the same viewport dimensions

Best Practices

Always verify the first rendered image before batch rendering
Use CSS Grid/Flexbox for layout -- most reliable across renderers
Avoid animations/transitions (static screenshot only)
For rounded corners on images, use CSS border-radius + overflow
For emoji rendering, rely on system fonts (Windows: Segoe UI Emoji)
Test text overflow -- ensure no content is clipped unexpectedly
Keep HTML files alongside output PNGs for easy re-rendering

Typography & Readability Rules

Text must be legible in the target platform's smallest viewing context (mobile feed for social platforms). Text inside linked or embedded image files (JPG, PNG, base64 assets) is decorative and exempt. All HTML text nodes and inline SVG text are subject to these rules.

These are HARD minimums -- never go below them for readable text.

Minimum Font Sizes by Platform

Text Role	Instagram Post/Carousel	Instagram Story/Reel	LinkedIn/Facebook	YouTube Thumb
Hero / Display	58px	56px	40px	60px
Heading	43px	42px	32px	36px
Body / Bullets	34px	32px	24px	36px
Caption / Footer	24px	20px	20px	32px

Universal rule: No text element meant to be read may use a font size smaller than 20px, on any platform.

Font Weight

Body text and above: use font-weight 500+ (medium/semibold/bold)
Caption text: font-weight 500+ strongly recommended; 400 only with explicit high-contrast background (4.5:1 ratio minimum)
Avoid thin/light weights (100-300) for any readable text

Verification Checklist

Before calling browser_take_screenshot, scan your HTML and confirm:

All text elements use explicit px sizes (not em/rem that could resolve smaller)
No heading is below the Heading minimum for the target platform
No body/bullet text is below the Body minimum
No footer or metadata text is below the Caption minimum
No readable text uses font-weight below 500 (caption at 400 only with 4.5:1 contrast background)

Available operations

Render HTML to PNG -- Convert self-contained HTML/CSS into a pixel-perfect screenshot
Batch Render -- Render multiple slides/pages sequentially for carousels and multi-image content
Viewport Resize -- Set precise viewport dimensions for any target platform
Quality Verification -- Visually inspect rendered output and re-render if needed

image-creator