PDF Tools

PDF Tools

The thin slice of PDF engineering that needs a real browser, an archival converter, a signer, or qpdf. Everything else — merging, page edits, watermarks, form filling, redaction, stamping — is one or two pymupdf calls; no skill required.

When to use: Generating pixel-perfect PDFs from HTML/React, converting or validating PDF/A, tagging PDFs for accessibility, digitally signing documents, or repairing/encrypting/linearizing PDFs with qpdf.

When NOT to use:

• Content extraction (text, tables, OCR, Markdown) → use the parse-docs skill, which routes to pdf-to-markdown, pymupdf-pdf, liteparse, or mineru.
• Routine page edits (merge, split, rotate, crop, watermark, fill forms, redact) → pymupdf directly: insert_pdf, set_toc, insert_textbox, show_pdf_page, apply_redactions, widget field updates.

Prerequisites — install check

Check what your task needs and install only what's missing — a missing tool is not an error unless your workflow reaches for it.

Check

# Node.js >= 22 — required by Puppeteer 25.x
node --version

# JS packages — run from the project that will use them
for pkg in puppeteer @signpdf/signpdf; do
  npm ls --depth=0 "$pkg" >/dev/null 2>&1 && echo "$pkg: ok" || echo "$pkg: MISSING"
done

# CLI tools
for cmd in qpdf gs verapdf; do
  command -v "$cmd" >/dev/null 2>&1 && echo "$cmd: ok" || echo "$cmd: MISSING"
done

Install

# JS — install into the project you're working in
npm i puppeteer                 # HTML→PDF; downloads its own Chromium
npm i @signpdf/signpdf @signpdf/signer-p12 @signpdf/placeholder-plain \
  @signpdf/utils                # digital signatures

# CLI — macOS
brew install qpdf ghostscript verapdf

# CLI — Debian/Ubuntu (verapdf is not packaged; download from docs.verapdf.org)
sudo apt install qpdf ghostscript

Puppeteer downloads its own Chromium at install — no separate Chrome needed. If the browser is missing (e.g. PUPPETEER_SKIP_DOWNLOAD was set), run npx puppeteer browsers install chrome.

Quick Reference

Common Mistakes

References

• High-Fidelity Generation -- Puppeteer HTML-to-PDF, CSS print tips, React templates, browser pooling
• Security and Archival -- qpdf encrypt/repair/linearize, PDF/A via ghostscript + verapdf, tagged PDFs, @signpdf signing

Self-Test

After changing SKILL.md or any reference, run the offline self-test. It checks structure (dead links, orphans), doc drift (deprecated API patterns, parse-docs routing consistency, the prerequisites Check block), and live-executes what's checkable offline (ghostscript). Missing deps SKIP with an install hint — they never fail:

python3 evals/selftest.py