kortix-ai PDF Processing
pypdf, pdfplumber, pymupdf, pdf2image, pypdfium2, pytesseract, reportlab, and pillow are pre-installed. Run Python files with python3 script.py. Use uv run --with <package> script.py only for a package that is not pre-installed.
Quick Start
from pypdf import PdfReader, PdfWriter
reader = PdfReader("document.pdf")
print(f"Pages: {len(reader.pages)}")
text = "".join(page.extract_text() or "" for page in reader.pages)
Use this for fast inspection. Move to the tool-specific sections below when you need layout-aware extraction, OCR, forms, rendering, or creation.
When to Use Which Tool
| Task | Tool | Details |
|---|---|---|
| Convert to Markdown | anydoc | anydoc document.pdf -o out.md — no OCR; scanned PDFs exit 1 |
| Create PDF from scratch | ReportLab | libraries/reportlab.md |
| Read / merge / split / rotate / encrypt | pypdf | — |
| Extract text and tables | pdfplumber | libraries/pdfplumber.md |
| Render pages to images | pypdfium2 | libraries/pypdfium2.md |
| Create/manipulate in JavaScript | pdf-lib | — |
| CLI merge/split/encrypt/optimize/repair | qpdf | libraries/cli-tools.md |
| CLI text extraction | pdftotext | libraries/cli-tools.md |
| CLI image extraction | pdfimages | libraries/cli-tools.md |
| CLI page rendering | pdftoppm | libraries/cli-tools.md |
| OCR scanned PDFs | pytesseract + pdf2image | Convert to images, then OCR |
| Fill PDF forms | pypdf or pdf-lib | form-filling.md |
| Convert PDF to Word | pdf2docx (load docx skill) | See docx skill — Converting PDF to Word |
Form filling: You MUST read form-filling.md before attempting to fill any PDF form.
Design and Typography
Design defaults: See skills/design-foundations/SKILL.md for palette, fonts + PDF pairings, chart colors, and core principles (1 accent + neutrals, no decorative imagery, accessibility).
Typography: PDFs embed any TTF font — use distinctive, professional fonts, not system defaults. Download from Google Fonts at runtime, register with ReportLab, and it embeds automatically. See libraries/reportlab.md (Custom Fonts section) and skills/design-foundations/SKILL.md (PDF Pairings table + Font Strategy by Format). Default to a clean sans-serif (Inter, DM Sans, Work Sans).
CJK text: Fonts like Inter and DM Sans only cover Latin glyphs. ReportLab has no automatic font fallback — unregistered scripts render as tofu. Register Noto Sans CJK for Chinese, Japanese, or Korean text. See libraries/reportlab.md (CJK Font Support).
Currency & symbol glyphs: The same Latin-only fonts also lack many currency and symbol glyphs — e.g. ₹ (U+20B9), ₩, ₫, ₴, ﷼. ReportLab and matplotlib render these as tofu with no fallback (matplotlib warns Glyph ... missing from font(s)). Either register a font that includes the glyph (e.g. Noto Sans), or use an ASCII fallback consistently (e.g. Rs for INR) across both charts and PDF body text so they match.
PDF Metadata
Always set metadata when creating PDFs:
- Author should default to
"Kortix"unless the user asks for a different organization or author name - Title should be a descriptive name relevant to the document contents
Canvas API: c.setTitle(...), c.setAuthor("Kortix") right after creating the canvas.
SimpleDocTemplate: pass title=..., author="Kortix" as constructor kwargs.
pdf-lib (JS): doc.setTitle(...), doc.setAuthor("Kortix").
Source Citations
Every PDF that includes information from web sources MUST have:
- Numbered superscript footnote markers in body text (using
<super>tags, never Unicode superscripts) - A numbered source list at the bottom of each page with clickable hyperlinked URLs
Each footnote entry must include the actual URL wrapped in an <a href> tag — never omit the URL or substitute a plain-text source name. See libraries/reportlab.md (Source Citations) for the implementation pattern.
Hyperlinks
All URLs in generated PDFs must be clickable. In ReportLab Paragraph objects, use <a href="..." color="blue"> markup. On the canvas, use canvas.linkURL(url, rect). See libraries/reportlab.md (Hyperlinks).
Subscripts and Superscripts
Never use Unicode subscript/superscript characters in ReportLab PDFs. Built-in fonts lack these glyphs, rendering them as black boxes. Use <sub> and <super> XML tags in Paragraph objects. For canvas text, manually adjust font size and y-offset. See libraries/reportlab.md (Subscripts and Superscripts).
Tips
Text extraction: pdftotext is the fastest option for plain text. Use pdfplumber when you need tables or coordinate data — don't use pypdf.extract_text() on large documents, it's slow.
Image extraction: pdfimages extracts embedded images directly and is much faster than rendering whole pages. Only render with pypdfium2 or pdftoppm when you need a visual snapshot of the page layout.
Large PDFs: Process pages individually or in chunks rather than loading the entire document. Use qpdf --split-pages to break up very large files before processing.
Encrypted PDFs: Use pypdf to detect and decrypt (reader.is_encrypted / reader.decrypt(pw)). If you don't have the password, try qpdf --password=X --decrypt. Run qpdf --show-encryption to inspect what protection is applied.
Corrupted PDFs: Run qpdf --check to diagnose structural problems, then qpdf --replace-input to attempt repair.
Verifying generated PDFs: Rendering pages to images (pypdfium2/pdftoppm) only helps if your model can view images. If it can't, verify via text extraction instead — dump page.extract_text() with pypdf and check content, ordering, and that nothing overflowed — and confirm metadata (title, author) is set.
Text extraction fails: If pdfplumber or pdftotext return empty/garbled text, the PDF is likely scanned images. Fall back to OCR (see below).
OCR for Scanned PDFs
import pytesseract
from pdf2image import convert_from_path
pages = convert_from_path("scan_output.pdf", dpi=300)
ocr_text = "\n\n".join(
f"--- Page {n} ---\n{pytesseract.image_to_string(pg)}"
for n, pg in enumerate(pages, 1)
)