b-open-io/html-to-pdf

HTML → PDF (Playwright pipeline)

Render print-ready PDFs from HTML/CSS via Playwright (Chromium). Use this for business cards, certificates, invoices, postcards, letterhead, one-pagers — anything that ends up as a printable PDF. The pipeline is template-driven so the same renderer produces minimal black-and-white cards, editorial watercolor cards, or any other style added later. For PDF post-processing (imposition, crop marks, front+back merging), chain into Skill(document-skills:pdf).

When to use

Trigger when the user asks for:

• "design a business card", "print business cards", "redesign Luke's card"
• "render HTML as PDF", "set up an HTML print pipeline"
• "make a printable PDF", "generate a one-pager / postcard / certificate"
• Anything involving bleed, safe area, web fonts in print, or QR codes on cards

Layout

html-to-pdf/
├── SKILL.md
├── README.md
├── scripts/
│   ├── render.ts            # Playwright renderer with template/style/theme selection
│   └── qr-artistic.ts       # Artistic QR generator (round dots, finder eyes, logo overlay)
├── templates/
│   └── business-cards/
│       ├── employees/       # Per-person JSON + photos
│       │   ├── example.json
│       │   └── README.md
│       ├── minimal/         # B/W editorial style — single theme
│       │   ├── card.html
│       │   └── card-back.html
│       └── watercolor/      # Editorial style with pixel-photo + watercolor back
│           ├── assets/      # Background images for both themes
│           │   ├── sky.png
│           │   └── mountains.png
│           ├── light/
│           │   ├── card.html
│           │   └── card-back.html
│           └── dark/
│               ├── card.html
│               └── card-back.html
└── references/
    ├── print-rules.md       # Bleed, font embed, color-profile gotchas
    └── creating-a-template.md  # How to add a new template / style / theme

Quick start

The renderer resolves all paths from the current working directory, so copy the skill files into a project root and run from there.

# Locate the skill — this varies by install method:
#   - Plugin install:  ls "$CLAUDE_PLUGIN_ROOT/skills/html-to-pdf"
#   - Cloned repo:     SKILL_ROOT="/path/to/prompts/skills/html-to-pdf"
#   - npx skills add:  ls .claude/skills/html-to-pdf
# Set SKILL_ROOT to whichever applies, then:
mkdir -p /tmp/print-job && cd /tmp/print-job
cp -R "$SKILL_ROOT/." .

# Install deps once
bun init -y
bun add playwright qrcode @types/qrcode geist @fontsource-variable/inter \
       @fontsource-variable/fraunces bootstrap-icons
bunx playwright install chromium

Render a business card (always run from /tmp/print-job):

# Minimal style — no theme, no photo needed
bun scripts/render.ts --template business-cards --style minimal --employee example

# Watercolor / light — needs a portrait
bun scripts/render.ts --template business-cards --style watercolor --theme light \
  --employee example --photo path/to/your-portrait.png

# Watercolor / dark — same template, same data, different theme
bun scripts/render.ts --template business-cards --style watercolor --theme dark \
  --employee example --photo path/to/your-portrait.png

# Add a logo to the QR center (optional, any SVG or PNG)
bun scripts/render.ts --template business-cards --style minimal --employee example \
  --logo path/to/your-logo.svg

Add a new employee by dropping employees/<slug>.json (use employees/example.json as the schema) and passing --employee <slug>.

Output lands in out/<slug>-<style>[-<theme>]-{front,back}.pdf.

Picking a style + theme

| Style | Theme | Tone | When to use | |---|---|---|---| | minimal | (none) | Editorial black-on-white, ample whitespace, blocky fade-out accent | Default. Reads as serious, professional, formal. Print shop friendly. | | watercolor | light | Cream/parchment surface, Fraunces serif name, pixel-art portrait stamped on the card, watercolor sky back | When the recipient needs to remember the card. Editorial, warmer. | | watercolor | dark | Slate-indigo surface, cyan accents, watercolor mountain night-scene back | Brand-matched to dark-mode bopen.io. Distinctive at crypto conferences. |

A new style is one directory. A new theme is one subdirectory inside a style. See references/creating-a-template.md.

The non-obvious rules

These are the gotchas that break silently if you skip them — full details in references/print-rules.md.

1. @page size + preferCSSPageSize: true — set the trim+bleed dimensions in BOTH the CSS @page rule and Playwright's page.pdf({ width, height, preferCSSPageSize: true }). Without preferCSSPageSize, Playwright silently falls back to US Letter.

2. -webkit-print-color-adjust: exact — without this, Chromium strips background colors and images from the PDF. Black-background card backs come out white.

3. Always embed fonts via @font-face — referencing only font-family: 'Inter', system-ui without an @font-face produces a PDF using whatever system-ui is on the build machine (SF Pro on macOS) embedded as Type 3 path glyphs. Different RIPs render Type 3 differently. Templates use __NODE_MODULES__/... placeholders so fonts always come from the installed npm package.

4. Wait for document.fonts.ready before page.pdf() — capturing before fonts apply produces a PDF with system fallback glyphs.

5. Bleed — render at trim + 2×0.125 in. The template HTMLs do this; new templates must too.

Full bleed/safe-area table, ghostscript/CMYK conversion notes, and font-embed troubleshooting live in references/print-rules.md.

Path placeholders in template HTML

So templates aren't tied to a specific filesystem layout, the renderer substitutes two tokens at render time:

| Placeholder | Resolves to | Use for | |---|---|---| | __NODE_MODULES__/... | node_modules/... (relative to working dir) | Web fonts, icon SVGs | | __ASSETS__/... | templates/<template>/<style>/assets/... | Style-specific background images |

The template HTML can be moved to any project layout — the renderer fills in the paths.

Data-field placeholders (employee data)

| Placeholder | From employee JSON | Notes | |---|---|---| | __NAME__ | name | Display name | | __TITLE__ | title | Role / subtitle | | __EMAIL__ | email | HTML-escaped | | __PHONE__ | phone | Optional | | __HANDLE__ | handle | Optional, rendered with X glyph | | __PHOTO_SRC__ | --photo <path> CLI arg | Required for templates that show a portrait | | __QR_SVG__ | Generated from qrUrl | Artistic QR with optional logo overlay | | __QR_LABEL__ | qrLabel (defaults to qrUrl) | Display text below the QR |

Every employee data field is HTML-escaped in the substitution step so a hostile name field can't inject script into the rendered page.

Known limitation: the substitution map in scripts/render.ts is currently hard-coded to the business-card field set. A new template that introduces fields like __EVENT__ or __VENUE__ requires extending the renderer. The clean refactor — looping the JSON object and substituting __<KEY-UPPERCASED>__ for each value — is deferred until a second non-card template lands. See references/creating-a-template.md.

Artistic QR codes

The bundled scripts/qr-artistic.ts generator builds the QR SVG by hand from the matrix returned by qrcode.create(). It supports:

• Round, rounded-square, or square data modules
• Custom rounded-square "eye" finder patterns
• A centered logo overlay (uses error-correction level H — up to ~22% of the QR width is recoverable)
• Configurable quiet zone (for cards where the QR sits directly on a non-uniform surface like a watercolor)

Always test the rendered QR by scanning the PDF with a phone camera before sending to print. Round-dot QRs with logo overlays can occasionally fail on cheap scanners even at level H.

Chaining with document-skills:pdf

After Playwright produces the per-page PDFs, invoke Skill(document-skills:pdf) for things HTML/CSS can't do:

• Merge front + back into a single 2-page deliverable
• 10-up imposition on US Letter for in-house cutting
• Crop marks / registration marks
• Embed PDF metadata (Title, Author, Producer)
• Compression / image downsampling

Adding new templates, styles, or themes

A new template is one directory. A new style under an existing template is one subdirectory. A new theme is one subdirectory inside a style.

templates/
└── <template>/                        # e.g. business-cards, postcards, certificates
    └── <style>/                       # e.g. minimal, watercolor, brutalist
        ├── card.html                  # if single-theme
        ├── card-back.html
        └── <theme>/                   # if multi-theme
            ├── card.html
            └── card-back.html

The renderer auto-discovers from the directory structure. See references/creating-a-template.md for a step-by-step walkthrough including the file fields each template HTML needs.

Provenance

This skill was extracted from the print pipeline behind bopen.io's business cards, where each teammate's QR resolves through a per-card vanity URL into the site's booking flow with attribution. The templates and gotchas reflect what actually held up at a commercial print shop.