Export PDF

Export PDF

Produce a PDF from an HTML artifact. Uses puppeteer's Page.pdf() which is lossless vector when the source is HTML/CSS/SVG.

Why puppeteer instead of Chrome DevTools MCP: the MCP does not expose Page.printToPDF directly (only take_screenshot, list_console_messages, evaluate_script, etc.). Using puppeteer via a Node script is deterministic and matches /export-pptx.

Preflight

1. Bash(which node) — required
2. Bash(test -d node_modules/puppeteer && echo yes || echo no) — if no, tell user /doctor or run npm i -D puppeteer

Steps

1. Resolve paths:

   • $0 = input HTML (required)
   • $1 = output (default: input with .pdf extension)
   • Bash(mkdir -p $(dirname <output>)) if needed

2. Run export script:

   Bash(node scripts/export-pdf.mjs "<input>" "<output>")
   

   (The script exists at scripts/export-pdf.mjs; if missing, write it per the template below.)

3. Report size + path.

Script template (scripts/export-pdf.mjs)

#!/usr/bin/env node
// Usage: node export-pdf.mjs <input.html> [output.pdf]
import puppeteer from 'puppeteer';
import { pathToFileURL } from 'node:url';
import path from 'node:path';
import fs from 'node:fs/promises';

const [, , input, output = input.replace(/\.html?$/i, '.pdf')] = process.argv;
if (!input) { console.error('Usage: export-pdf.mjs <input.html> [output.pdf]'); process.exit(1); }

const inAbs = path.resolve(process.cwd(), input);
const outAbs = path.resolve(process.cwd(), output);

const browser = await puppeteer.launch({ args: ['--no-sandbox'] });
const page = await browser.newPage();
await page.goto(pathToFileURL(inAbs).toString(), { waitUntil: 'networkidle0' });

// If it's a deck, set noscale so deck-stage renders at natural dims
const deckDims = await page.evaluate(() => {
  const d = document.querySelector('deck-stage');
  if (!d) return null;
  d.setAttribute('noscale', '');
  return [parseInt(d.getAttribute('width') || '1920', 10), parseInt(d.getAttribute('height') || '1080', 10)];
});

await page.emulateMediaType('print');
const pdfOpts = {
  path: outAbs,
  printBackground: true,
};
if (deckDims) {
  // Deck: one section per page — @media print in deck_stage.js handles page-break
  pdfOpts.width = `${deckDims[0]}px`;
  pdfOpts.height = `${deckDims[1]}px`;
  pdfOpts.pageRanges = '';
} else {
  pdfOpts.format = 'A4';
}

await page.pdf(pdfOpts);
await browser.close();

const stat = await fs.stat(outAbs);
console.log(`wrote ${outAbs} (${(stat.size / 1024).toFixed(1)} KB)`);

Notes

• For decks: deck_stage.js must have @media print { @page { size: ... } section { page-break-after: always } } in the global <style> it injects — already present.
• For general pages: defaults to A4. To override, user can pass inline CSS @page { size: letter } or similar.
• networkidle0 waits for all network activity to stop — if artifact uses lazy images, bump timeout to 15000ms.