---
name: pdf
description: >-
  Use this skill whenever the user wants to do anything with PDF files. This
  includes reading or extracting text/tables from PDFs, combining or merging
  multiple PDFs into one, splitting PDFs apart, rotating pages, adding
  watermarks, creating new PDFs, filling PDF forms, encrypting/decrypting PDFs,
  extracting images, and OCR on scanned PDFs to make them searchable. If the
  user mentions a .pdf file or asks to produce one, use this skill. Use when
  用户提到 PDF、读取PDF、合并PDF、拆分PDF、填写表单、加水印、提取文字、
  扫描识别。
version: 1.0.2
type: procedural
risk_level: low
status: enabled
disable-model-invocation: true
tags:
  - pdf
  - document
  - form
  - ocr
metadata:
  author: anthropic
  updated_at: '2026-04-13'
  i18n:
    default_locale: en-US
    source_locale: zh-CN
    locales:
      - zh-CN
      - en-US
    zh-CN:
      name: PDF 文档处理
      short_desc: 读取、创建、合并、拆分和填写 PDF 文档
      description: >-
        Use this skill whenever the user wants to do anything with PDF files. This includes reading or extracting text/tables from PDFs, combining or merging multiple PDFs into one, splitting PDFs apart, rotating pages, adding watermarks, creating new PDFs, filling PDF forms, encrypting/decrypting PDFs, extracting images, and OCR on scanned PDFs to make them searchable. If the user mentions a .pdf file or asks to produce one, use this skill. Use when 用户提到 PDF、读取PDF、合并PDF、拆分PDF、填写表单、加水印、提取文字、 扫描识别。
      body: ./SKILL.zh-CN.md
      source_hash: sha256:15805c1921ac2c1e
      translated_by: human
    en-US:
      name: PDF Document Processing
      short_desc: Read, create, merge, split, and fill PDF documents
      description: >-
        Use this skill whenever the user wants to do anything with PDF files. This includes reading or extracting text/tables from PDFs, combining or merging multiple PDFs into one, splitting PDFs apart, rotating pages, adding watermarks, creating new PDFs, filling PDF forms, encrypting/decrypting PDFs, extracting images, and OCR on scanned PDFs to make them searchable. If the user mentions a .pdf file or asks to produce one, use this skill. Use when the user mentions PDF, reading PDFs, merging PDFs, splitting PDFs, filling forms, adding watermarks, extracting text, or OCR.
      body: ./SKILL.md
      source_hash: sha256:15805c1921ac2c1e
      translated_by: ai:claude-opus-4-7
      translated_at: '2026-05-03'
market:
  icon: >-
    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0
    24 24" fill="none"><defs><linearGradient id="pd-a" x1="4" y1="2" x2="20"
    y2="22" gradientUnits="userSpaceOnUse"><stop stop-color="#FF3B30"/><stop
    offset="1" stop-color="#FF9500"/></linearGradient></defs><path d="M14
    2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"
    fill="url(#pd-a)" fill-opacity="0.1" stroke="url(#pd-a)"
    stroke-width="1.5"/><path d="M14 2v6h6" stroke="url(#pd-a)"
    stroke-width="1.5" stroke-linejoin="round"/><path d="M8 13h8M8 17h5"
    stroke="url(#pd-a)" stroke-width="1.3" stroke-linecap="round"/><path
    d="M17 11v6l2-1.5 2 1.5v-6z" fill="#FF3B30"
    fill-opacity="0.8"/></svg>
  category: productivity
  maintainer:
    name: DesireCore Official
    verified: true
  channel: latest
---

# pdf skill

## L0: One-Sentence Summary

Read, create, merge, split, and fill PDF documents, with OCR support and command-line tools.

## L1: Overview and Use Cases

### Capability Description

pdf is a **Procedural Skill** that provides full PDF document processing capabilities. Built on Python libraries (pypdf, pdfplumber, reportlab) and command-line tools (qpdf, pdftotext, pdftk), it supports text extraction, table extraction, merging/splitting, rotation, watermarking, encryption, form filling, and OCR.

### Use Cases

- The user needs to extract text or table data from a PDF
- The user needs to merge multiple PDFs or split pages
- The user needs to create a new PDF document
- The user needs to fill PDF forms, add watermarks, or encrypt PDFs

## L2: Detailed Specification

## Prerequisites

### Python 3 (required)

Before performing any Python operation, check that Python is available:

```bash
python3 --version 2>/dev/null || python --version 2>/dev/null
```

If the command fails (Python is not available), **you must stop and tell the user to install Python 3**:

- **macOS**: `brew install python3`, or download from https://www.python.org/downloads/
- **Windows**: `winget install Python.Python.3`, or download from python.org (check "Add Python to PATH" during installation)
- **Linux (Debian/Ubuntu)**: `sudo apt install python3 python3-pip`
- **Linux (Fedora/RHEL)**: `sudo dnf install python3 python3-pip`

For more detailed environment setup help: load the `python-runtime` skill for Python issues;
load the `dev-environment-setup` skill for everything else (system tools like poppler / tesseract, containers / WSL).

### Python Package Dependencies

This skill depends on the following Python packages (checked on demand):

- `pypdf` — Basic PDF operations (read, merge, split, rotate)
- `pdfplumber` — Table extraction, layout-aware text extraction
- `Pillow` — Image processing (watermarks, verification images, etc.)
- `reportlab` — PDF creation (optional, install on demand)
- `pdf2image` — PDF-to-image conversion (optional, requires poppler)

Core package check:
```bash
python3 -c "import pypdf; import pdfplumber; import PIL" 2>/dev/null || echo "MISSING"
```

If missing, tell the user to install: `pip install pypdf pdfplumber Pillow`

## Output Rule

When you create or modify a .pdf file, you **MUST** tell the user the absolute path of the output file in your response. Example: "File saved to: `/path/to/output.pdf`"

## Overview

This guide covers essential PDF processing operations using Python libraries and command-line tools. For advanced features, JavaScript libraries, and detailed examples, see REFERENCE.md. If you need to fill out a PDF form, read FORMS.md and follow its instructions.

## Quick Start

```python
from pypdf import PdfReader, PdfWriter

# Read a PDF
reader = PdfReader("document.pdf")
print(f"Pages: {len(reader.pages)}")

# Extract text
text = ""
for page in reader.pages:
    text += page.extract_text()
```

## Python Libraries

### pypdf - Basic Operations

#### Merge PDFs
```python
from pypdf import PdfWriter, PdfReader

writer = PdfWriter()
for pdf_file in ["doc1.pdf", "doc2.pdf", "doc3.pdf"]:
    reader = PdfReader(pdf_file)
    for page in reader.pages:
        writer.add_page(page)

with open("merged.pdf", "wb") as output:
    writer.write(output)
```

#### Split PDF
```python
reader = PdfReader("input.pdf")
for i, page in enumerate(reader.pages):
    writer = PdfWriter()
    writer.add_page(page)
    with open(f"page_{i+1}.pdf", "wb") as output:
        writer.write(output)
```

#### Extract Metadata
```python
reader = PdfReader("document.pdf")
meta = reader.metadata
print(f"Title: {meta.title}")
print(f"Author: {meta.author}")
print(f"Subject: {meta.subject}")
print(f"Creator: {meta.creator}")
```

#### Rotate Pages
```python
reader = PdfReader("input.pdf")
writer = PdfWriter()

page = reader.pages[0]
page.rotate(90)  # Rotate 90 degrees clockwise
writer.add_page(page)

with open("rotated.pdf", "wb") as output:
    writer.write(output)
```

### pdfplumber - Text and Table Extraction

#### Extract Text with Layout
```python
import pdfplumber

with pdfplumber.open("document.pdf") as pdf:
    for page in pdf.pages:
        text = page.extract_text()
        print(text)
```

#### Extract Tables
```python
with pdfplumber.open("document.pdf") as pdf:
    for i, page in enumerate(pdf.pages):
        tables = page.extract_tables()
        for j, table in enumerate(tables):
            print(f"Table {j+1} on page {i+1}:")
            for row in table:
                print(row)
```

#### Advanced Table Extraction
```python
import pandas as pd

with pdfplumber.open("document.pdf") as pdf:
    all_tables = []
    for page in pdf.pages:
        tables = page.extract_tables()
        for table in tables:
            if table:  # Check if table is not empty
                df = pd.DataFrame(table[1:], columns=table[0])
                all_tables.append(df)

# Combine all tables
if all_tables:
    combined_df = pd.concat(all_tables, ignore_index=True)
    combined_df.to_excel("extracted_tables.xlsx", index=False)
```

### reportlab - Create PDFs

#### Basic PDF Creation
```python
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas

c = canvas.Canvas("hello.pdf", pagesize=letter)
width, height = letter

# Add text
c.drawString(100, height - 100, "Hello World!")
c.drawString(100, height - 120, "This is a PDF created with reportlab")

# Add a line
c.line(100, height - 140, 400, height - 140)

# Save
c.save()
```

#### Create PDF with Multiple Pages
```python
from reportlab.lib.pagesizes import letter
from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, PageBreak
from reportlab.lib.styles import getSampleStyleSheet

doc = SimpleDocTemplate("report.pdf", pagesize=letter)
styles = getSampleStyleSheet()
story = []

# Add content
title = Paragraph("Report Title", styles['Title'])
story.append(title)
story.append(Spacer(1, 12))

body = Paragraph("This is the body of the report. " * 20, styles['Normal'])
story.append(body)
story.append(PageBreak())

# Page 2
story.append(Paragraph("Page 2", styles['Heading1']))
story.append(Paragraph("Content for page 2", styles['Normal']))

# Build PDF
doc.build(story)
```

#### Subscripts and Superscripts

**IMPORTANT**: Never use Unicode subscript/superscript characters (₀₁₂₃₄₅₆₇₈₉, ⁰¹²³⁴⁵⁶⁷⁸⁹) in ReportLab PDFs. The built-in fonts do not include these glyphs, causing them to render as solid black boxes.

Instead, use ReportLab's XML markup tags in Paragraph objects:
```python
from reportlab.platypus import Paragraph
from reportlab.lib.styles import getSampleStyleSheet

styles = getSampleStyleSheet()

# Subscripts: use <sub> tag
chemical = Paragraph("H<sub>2</sub>O", styles['Normal'])

# Superscripts: use <super> tag
squared = Paragraph("x<super>2</super> + y<super>2</super>", styles['Normal'])
```

For canvas-drawn text (not Paragraph objects), manually adjust font the size and position rather than using Unicode subscripts/superscripts.

## Command-Line Tools

### pdftotext (poppler-utils)
```bash
# Extract text
pdftotext input.pdf output.txt

# Extract text preserving layout
pdftotext -layout input.pdf output.txt

# Extract specific pages
pdftotext -f 1 -l 5 input.pdf output.txt  # Pages 1-5
```

### qpdf
```bash
# Merge PDFs
qpdf --empty --pages file1.pdf file2.pdf -- merged.pdf

# Split pages
qpdf input.pdf --pages . 1-5 -- pages1-5.pdf
qpdf input.pdf --pages . 6-10 -- pages6-10.pdf

# Rotate pages
qpdf input.pdf output.pdf --rotate=+90:1  # Rotate page 1 by 90 degrees

# Remove password
qpdf --password=mypassword --decrypt encrypted.pdf decrypted.pdf
```

### pdftk (if available)
```bash
# Merge
pdftk file1.pdf file2.pdf cat output merged.pdf

# Split
pdftk input.pdf burst

# Rotate
pdftk input.pdf rotate 1east output rotated.pdf
```

## Common Tasks

### Extract Text from Scanned PDFs
```python
# Requires: pip install pytesseract pdf2image
import pytesseract
from pdf2image import convert_from_path

# Convert PDF to images
images = convert_from_path('scanned.pdf')

# OCR each page
text = ""
for i, image in enumerate(images):
    text += f"Page {i+1}:\n"
    text += pytesseract.image_to_string(image)
    text += "\n\n"

print(text)
```

### Add Watermark
```python
from pypdf import PdfReader, PdfWriter

# Create watermark (or load existing)
watermark = PdfReader("watermark.pdf").pages[0]

# Apply to all pages
reader = PdfReader("document.pdf")
writer = PdfWriter()

for page in reader.pages:
    page.merge_page(watermark)
    writer.add_page(page)

with open("watermarked.pdf", "wb") as output:
    writer.write(output)
```

### Extract Images
```bash
# Using pdfimages (poppler-utils)
pdfimages -j input.pdf output_prefix

# This extracts all images as output_prefix-000.jpg, output_prefix-001.jpg, etc.
```

### Password Protection
```python
from pypdf import PdfReader, PdfWriter

reader = PdfReader("input.pdf")
writer = PdfWriter()

for page in reader.pages:
    writer.add_page(page)

# Add password
writer.encrypt("userpassword", "ownerpassword")

with open("encrypted.pdf", "wb") as output:
    writer.write(output)
```

## Quick Reference

| Task | Best Tool | Command/Code |
|------|-----------|--------------|
| Merge PDFs | pypdf | `writer.add_page(page)` |
| Split PDFs | pypdf | One page per file |
| Extract text | pdfplumber | `page.extract_text()` |
| Extract tables | pdfplumber | `page.extract_tables()` |
| Create PDFs | reportlab | Canvas or Platypus |
| Command line merge | qpdf | `qpdf --empty --pages ...` |
| OCR scanned PDFs | pytesseract | Convert to image first |
| Fill PDF forms | pdf-lib or pypdf (see FORMS.md) | See FORMS.md |

## Next Steps

- For advanced pypdfium2 usage, see REFERENCE.md
- For JavaScript libraries (pdf-lib), see REFERENCE.md
- If you need to fill out a PDF form, follow the instructions in FORMS.md
- For troubleshooting guides, see REFERENCE.md
