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pdf

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.

Packaged view

This page reorganizes the original catalog entry around fit, installability, and workflow context first. The original raw source lives below.

Stars
0
Hot score
74
Updated
March 20, 2026
Overall rating
C0.0
Composite score
0.0
Best-practice grade
C62.8

Install command

npx @skill-hub/cli install thewatcher01-skills-pdf

Repository

TheWatcher01/skills

Skill path: skills/pdf

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.

Open repository

Best for

Primary workflow: Ship Full Stack.

Technical facets: Full Stack.

Target audience: everyone.

License: Unknown.

Original source

Catalog source: SkillHub Club.

Repository owner: TheWatcher01.

This is still a mirrored public skill entry. Review the repository before installing into production workflows.

What it helps with

  • Install pdf into Claude Code, Codex CLI, Gemini CLI, or OpenCode workflows
  • Review https://github.com/TheWatcher01/skills before adding pdf to shared team environments
  • Use pdf for development workflows

Works across

Claude CodeCodex CLIGemini CLIOpenCode

Favorites: 0.

Sub-skills: 0.

Aggregator: No.

Original source / Raw SKILL.md

---
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.
---

# PDF Processing Guide

## 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


---

## Skill Companion Files

> Additional files collected from the skill directory layout.

### scripts/check_bounding_boxes.py

```python
from dataclasses import dataclass
import json
import sys




@dataclass
class RectAndField:
    rect: list[float]
    rect_type: str
    field: dict


def get_bounding_box_messages(fields_json_stream) -> list[str]:
    messages = []
    fields = json.load(fields_json_stream)
    messages.append(f"Read {len(fields['form_fields'])} fields")

    def rects_intersect(r1, r2):
        disjoint_horizontal = r1[0] >= r2[2] or r1[2] <= r2[0]
        disjoint_vertical = r1[1] >= r2[3] or r1[3] <= r2[1]
        return not (disjoint_horizontal or disjoint_vertical)

    rects_and_fields = []
    for f in fields["form_fields"]:
        rects_and_fields.append(RectAndField(f["label_bounding_box"], "label", f))
        rects_and_fields.append(RectAndField(f["entry_bounding_box"], "entry", f))

    has_error = False
    for i, ri in enumerate(rects_and_fields):
        for j in range(i + 1, len(rects_and_fields)):
            rj = rects_and_fields[j]
            if ri.field["page_number"] == rj.field["page_number"] and rects_intersect(ri.rect, rj.rect):
                has_error = True
                if ri.field is rj.field:
                    messages.append(f"FAILURE: intersection between label and entry bounding boxes for `{ri.field['description']}` ({ri.rect}, {rj.rect})")
                else:
                    messages.append(f"FAILURE: intersection between {ri.rect_type} bounding box for `{ri.field['description']}` ({ri.rect}) and {rj.rect_type} bounding box for `{rj.field['description']}` ({rj.rect})")
                if len(messages) >= 20:
                    messages.append("Aborting further checks; fix bounding boxes and try again")
                    return messages
        if ri.rect_type == "entry":
            if "entry_text" in ri.field:
                font_size = ri.field["entry_text"].get("font_size", 14)
                entry_height = ri.rect[3] - ri.rect[1]
                if entry_height < font_size:
                    has_error = True
                    messages.append(f"FAILURE: entry bounding box height ({entry_height}) for `{ri.field['description']}` is too short for the text content (font size: {font_size}). Increase the box height or decrease the font size.")
                    if len(messages) >= 20:
                        messages.append("Aborting further checks; fix bounding boxes and try again")
                        return messages

    if not has_error:
        messages.append("SUCCESS: All bounding boxes are valid")
    return messages

if __name__ == "__main__":
    if len(sys.argv) != 2:
        print("Usage: check_bounding_boxes.py [fields.json]")
        sys.exit(1)
    with open(sys.argv[1]) as f:
        messages = get_bounding_box_messages(f)
    for msg in messages:
        print(msg)

```

### scripts/check_fillable_fields.py

```python
import sys
from pypdf import PdfReader




reader = PdfReader(sys.argv[1])
if (reader.get_fields()):
    print("This PDF has fillable form fields")
else:
    print("This PDF does not have fillable form fields; you will need to visually determine where to enter data")

```

### scripts/convert_pdf_to_images.py

```python
import os
import sys

from pdf2image import convert_from_path




def convert(pdf_path, output_dir, max_dim=1000):
    images = convert_from_path(pdf_path, dpi=200)

    for i, image in enumerate(images):
        width, height = image.size
        if width > max_dim or height > max_dim:
            scale_factor = min(max_dim / width, max_dim / height)
            new_width = int(width * scale_factor)
            new_height = int(height * scale_factor)
            image = image.resize((new_width, new_height))
        
        image_path = os.path.join(output_dir, f"page_{i+1}.png")
        image.save(image_path)
        print(f"Saved page {i+1} as {image_path} (size: {image.size})")

    print(f"Converted {len(images)} pages to PNG images")


if __name__ == "__main__":
    if len(sys.argv) != 3:
        print("Usage: convert_pdf_to_images.py [input pdf] [output directory]")
        sys.exit(1)
    pdf_path = sys.argv[1]
    output_directory = sys.argv[2]
    convert(pdf_path, output_directory)

```

### scripts/create_validation_image.py

```python
import json
import sys

from PIL import Image, ImageDraw




def create_validation_image(page_number, fields_json_path, input_path, output_path):
    with open(fields_json_path, 'r') as f:
        data = json.load(f)

        img = Image.open(input_path)
        draw = ImageDraw.Draw(img)
        num_boxes = 0
        
        for field in data["form_fields"]:
            if field["page_number"] == page_number:
                entry_box = field['entry_bounding_box']
                label_box = field['label_bounding_box']
                draw.rectangle(entry_box, outline='red', width=2)
                draw.rectangle(label_box, outline='blue', width=2)
                num_boxes += 2
        
        img.save(output_path)
        print(f"Created validation image at {output_path} with {num_boxes} bounding boxes")


if __name__ == "__main__":
    if len(sys.argv) != 5:
        print("Usage: create_validation_image.py [page number] [fields.json file] [input image path] [output image path]")
        sys.exit(1)
    page_number = int(sys.argv[1])
    fields_json_path = sys.argv[2]
    input_image_path = sys.argv[3]
    output_image_path = sys.argv[4]
    create_validation_image(page_number, fields_json_path, input_image_path, output_image_path)

```

### scripts/extract_form_field_info.py

```python
import json
import sys

from pypdf import PdfReader




def get_full_annotation_field_id(annotation):
    components = []
    while annotation:
        field_name = annotation.get('/T')
        if field_name:
            components.append(field_name)
        annotation = annotation.get('/Parent')
    return ".".join(reversed(components)) if components else None


def make_field_dict(field, field_id):
    field_dict = {"field_id": field_id}
    ft = field.get('/FT')
    if ft == "/Tx":
        field_dict["type"] = "text"
    elif ft == "/Btn":
        field_dict["type"] = "checkbox"  
        states = field.get("/_States_", [])
        if len(states) == 2:
            if "/Off" in states:
                field_dict["checked_value"] = states[0] if states[0] != "/Off" else states[1]
                field_dict["unchecked_value"] = "/Off"
            else:
                print(f"Unexpected state values for checkbox `${field_id}`. Its checked and unchecked values may not be correct; if you're trying to check it, visually verify the results.")
                field_dict["checked_value"] = states[0]
                field_dict["unchecked_value"] = states[1]
    elif ft == "/Ch":
        field_dict["type"] = "choice"
        states = field.get("/_States_", [])
        field_dict["choice_options"] = [{
            "value": state[0],
            "text": state[1],
        } for state in states]
    else:
        field_dict["type"] = f"unknown ({ft})"
    return field_dict


def get_field_info(reader: PdfReader):
    fields = reader.get_fields()

    field_info_by_id = {}
    possible_radio_names = set()

    for field_id, field in fields.items():
        if field.get("/Kids"):
            if field.get("/FT") == "/Btn":
                possible_radio_names.add(field_id)
            continue
        field_info_by_id[field_id] = make_field_dict(field, field_id)


    radio_fields_by_id = {}

    for page_index, page in enumerate(reader.pages):
        annotations = page.get('/Annots', [])
        for ann in annotations:
            field_id = get_full_annotation_field_id(ann)
            if field_id in field_info_by_id:
                field_info_by_id[field_id]["page"] = page_index + 1
                field_info_by_id[field_id]["rect"] = ann.get('/Rect')
            elif field_id in possible_radio_names:
                try:
                    on_values = [v for v in ann["/AP"]["/N"] if v != "/Off"]
                except KeyError:
                    continue
                if len(on_values) == 1:
                    rect = ann.get("/Rect")
                    if field_id not in radio_fields_by_id:
                        radio_fields_by_id[field_id] = {
                            "field_id": field_id,
                            "type": "radio_group",
                            "page": page_index + 1,
                            "radio_options": [],
                        }
                    radio_fields_by_id[field_id]["radio_options"].append({
                        "value": on_values[0],
                        "rect": rect,
                    })

    fields_with_location = []
    for field_info in field_info_by_id.values():
        if "page" in field_info:
            fields_with_location.append(field_info)
        else:
            print(f"Unable to determine location for field id: {field_info.get('field_id')}, ignoring")

    def sort_key(f):
        if "radio_options" in f:
            rect = f["radio_options"][0]["rect"] or [0, 0, 0, 0]
        else:
            rect = f.get("rect") or [0, 0, 0, 0]
        adjusted_position = [-rect[1], rect[0]]
        return [f.get("page"), adjusted_position]
    
    sorted_fields = fields_with_location + list(radio_fields_by_id.values())
    sorted_fields.sort(key=sort_key)

    return sorted_fields


def write_field_info(pdf_path: str, json_output_path: str):
    reader = PdfReader(pdf_path)
    field_info = get_field_info(reader)
    with open(json_output_path, "w") as f:
        json.dump(field_info, f, indent=2)
    print(f"Wrote {len(field_info)} fields to {json_output_path}")


if __name__ == "__main__":
    if len(sys.argv) != 3:
        print("Usage: extract_form_field_info.py [input pdf] [output json]")
        sys.exit(1)
    write_field_info(sys.argv[1], sys.argv[2])

```

### scripts/extract_form_structure.py

```python
"""
Extract form structure from a non-fillable PDF.

This script analyzes the PDF to find:
- Text labels with their exact coordinates
- Horizontal lines (row boundaries)
- Checkboxes (small rectangles)

Output: A JSON file with the form structure that can be used to generate
accurate field coordinates for filling.

Usage: python extract_form_structure.py <input.pdf> <output.json>
"""

import json
import sys
import pdfplumber


def extract_form_structure(pdf_path):
    structure = {
        "pages": [],
        "labels": [],
        "lines": [],
        "checkboxes": [],
        "row_boundaries": []
    }

    with pdfplumber.open(pdf_path) as pdf:
        for page_num, page in enumerate(pdf.pages, 1):
            structure["pages"].append({
                "page_number": page_num,
                "width": float(page.width),
                "height": float(page.height)
            })

            words = page.extract_words()
            for word in words:
                structure["labels"].append({
                    "page": page_num,
                    "text": word["text"],
                    "x0": round(float(word["x0"]), 1),
                    "top": round(float(word["top"]), 1),
                    "x1": round(float(word["x1"]), 1),
                    "bottom": round(float(word["bottom"]), 1)
                })

            for line in page.lines:
                if abs(float(line["x1"]) - float(line["x0"])) > page.width * 0.5:
                    structure["lines"].append({
                        "page": page_num,
                        "y": round(float(line["top"]), 1),
                        "x0": round(float(line["x0"]), 1),
                        "x1": round(float(line["x1"]), 1)
                    })

            for rect in page.rects:
                width = float(rect["x1"]) - float(rect["x0"])
                height = float(rect["bottom"]) - float(rect["top"])
                if 5 <= width <= 15 and 5 <= height <= 15 and abs(width - height) < 2:
                    structure["checkboxes"].append({
                        "page": page_num,
                        "x0": round(float(rect["x0"]), 1),
                        "top": round(float(rect["top"]), 1),
                        "x1": round(float(rect["x1"]), 1),
                        "bottom": round(float(rect["bottom"]), 1),
                        "center_x": round((float(rect["x0"]) + float(rect["x1"])) / 2, 1),
                        "center_y": round((float(rect["top"]) + float(rect["bottom"])) / 2, 1)
                    })

    lines_by_page = {}
    for line in structure["lines"]:
        page = line["page"]
        if page not in lines_by_page:
            lines_by_page[page] = []
        lines_by_page[page].append(line["y"])

    for page, y_coords in lines_by_page.items():
        y_coords = sorted(set(y_coords))
        for i in range(len(y_coords) - 1):
            structure["row_boundaries"].append({
                "page": page,
                "row_top": y_coords[i],
                "row_bottom": y_coords[i + 1],
                "row_height": round(y_coords[i + 1] - y_coords[i], 1)
            })

    return structure


def main():
    if len(sys.argv) != 3:
        print("Usage: extract_form_structure.py <input.pdf> <output.json>")
        sys.exit(1)

    pdf_path = sys.argv[1]
    output_path = sys.argv[2]

    print(f"Extracting structure from {pdf_path}...")
    structure = extract_form_structure(pdf_path)

    with open(output_path, "w") as f:
        json.dump(structure, f, indent=2)

    print(f"Found:")
    print(f"  - {len(structure['pages'])} pages")
    print(f"  - {len(structure['labels'])} text labels")
    print(f"  - {len(structure['lines'])} horizontal lines")
    print(f"  - {len(structure['checkboxes'])} checkboxes")
    print(f"  - {len(structure['row_boundaries'])} row boundaries")
    print(f"Saved to {output_path}")


if __name__ == "__main__":
    main()

```

### scripts/fill_fillable_fields.py

```python
import json
import sys

from pypdf import PdfReader, PdfWriter

from extract_form_field_info import get_field_info




def fill_pdf_fields(input_pdf_path: str, fields_json_path: str, output_pdf_path: str):
    with open(fields_json_path) as f:
        fields = json.load(f)
    fields_by_page = {}
    for field in fields:
        if "value" in field:
            field_id = field["field_id"]
            page = field["page"]
            if page not in fields_by_page:
                fields_by_page[page] = {}
            fields_by_page[page][field_id] = field["value"]
    
    reader = PdfReader(input_pdf_path)

    has_error = False
    field_info = get_field_info(reader)
    fields_by_ids = {f["field_id"]: f for f in field_info}
    for field in fields:
        existing_field = fields_by_ids.get(field["field_id"])
        if not existing_field:
            has_error = True
            print(f"ERROR: `{field['field_id']}` is not a valid field ID")
        elif field["page"] != existing_field["page"]:
            has_error = True
            print(f"ERROR: Incorrect page number for `{field['field_id']}` (got {field['page']}, expected {existing_field['page']})")
        else:
            if "value" in field:
                err = validation_error_for_field_value(existing_field, field["value"])
                if err:
                    print(err)
                    has_error = True
    if has_error:
        sys.exit(1)

    writer = PdfWriter(clone_from=reader)
    for page, field_values in fields_by_page.items():
        writer.update_page_form_field_values(writer.pages[page - 1], field_values, auto_regenerate=False)

    writer.set_need_appearances_writer(True)
    
    with open(output_pdf_path, "wb") as f:
        writer.write(f)


def validation_error_for_field_value(field_info, field_value):
    field_type = field_info["type"]
    field_id = field_info["field_id"]
    if field_type == "checkbox":
        checked_val = field_info["checked_value"]
        unchecked_val = field_info["unchecked_value"]
        if field_value != checked_val and field_value != unchecked_val:
            return f'ERROR: Invalid value "{field_value}" for checkbox field "{field_id}". The checked value is "{checked_val}" and the unchecked value is "{unchecked_val}"'
    elif field_type == "radio_group":
        option_values = [opt["value"] for opt in field_info["radio_options"]]
        if field_value not in option_values:
            return f'ERROR: Invalid value "{field_value}" for radio group field "{field_id}". Valid values are: {option_values}' 
    elif field_type == "choice":
        choice_values = [opt["value"] for opt in field_info["choice_options"]]
        if field_value not in choice_values:
            return f'ERROR: Invalid value "{field_value}" for choice field "{field_id}". Valid values are: {choice_values}'
    return None


def monkeypatch_pydpf_method():
    from pypdf.generic import DictionaryObject
    from pypdf.constants import FieldDictionaryAttributes

    original_get_inherited = DictionaryObject.get_inherited

    def patched_get_inherited(self, key: str, default = None):
        result = original_get_inherited(self, key, default)
        if key == FieldDictionaryAttributes.Opt:
            if isinstance(result, list) and all(isinstance(v, list) and len(v) == 2 for v in result):
                result = [r[0] for r in result]
        return result

    DictionaryObject.get_inherited = patched_get_inherited


if __name__ == "__main__":
    if len(sys.argv) != 4:
        print("Usage: fill_fillable_fields.py [input pdf] [field_values.json] [output pdf]")
        sys.exit(1)
    monkeypatch_pydpf_method()
    input_pdf = sys.argv[1]
    fields_json = sys.argv[2]
    output_pdf = sys.argv[3]
    fill_pdf_fields(input_pdf, fields_json, output_pdf)

```

### scripts/fill_pdf_form_with_annotations.py

```python
import json
import sys

from pypdf import PdfReader, PdfWriter
from pypdf.annotations import FreeText




def transform_from_image_coords(bbox, image_width, image_height, pdf_width, pdf_height):
    x_scale = pdf_width / image_width
    y_scale = pdf_height / image_height

    left = bbox[0] * x_scale
    right = bbox[2] * x_scale

    top = pdf_height - (bbox[1] * y_scale)
    bottom = pdf_height - (bbox[3] * y_scale)

    return left, bottom, right, top


def transform_from_pdf_coords(bbox, pdf_height):
    left = bbox[0]
    right = bbox[2]

    pypdf_top = pdf_height - bbox[1]      
    pypdf_bottom = pdf_height - bbox[3]   

    return left, pypdf_bottom, right, pypdf_top


def fill_pdf_form(input_pdf_path, fields_json_path, output_pdf_path):
    
    with open(fields_json_path, "r") as f:
        fields_data = json.load(f)
    
    reader = PdfReader(input_pdf_path)
    writer = PdfWriter()
    
    writer.append(reader)
    
    pdf_dimensions = {}
    for i, page in enumerate(reader.pages):
        mediabox = page.mediabox
        pdf_dimensions[i + 1] = [mediabox.width, mediabox.height]
    
    annotations = []
    for field in fields_data["form_fields"]:
        page_num = field["page_number"]

        page_info = next(p for p in fields_data["pages"] if p["page_number"] == page_num)
        pdf_width, pdf_height = pdf_dimensions[page_num]

        if "pdf_width" in page_info:
            transformed_entry_box = transform_from_pdf_coords(
                field["entry_bounding_box"],
                float(pdf_height)
            )
        else:
            image_width = page_info["image_width"]
            image_height = page_info["image_height"]
            transformed_entry_box = transform_from_image_coords(
                field["entry_bounding_box"],
                image_width, image_height,
                float(pdf_width), float(pdf_height)
            )
        
        if "entry_text" not in field or "text" not in field["entry_text"]:
            continue
        entry_text = field["entry_text"]
        text = entry_text["text"]
        if not text:
            continue
        
        font_name = entry_text.get("font", "Arial")
        font_size = str(entry_text.get("font_size", 14)) + "pt"
        font_color = entry_text.get("font_color", "000000")

        annotation = FreeText(
            text=text,
            rect=transformed_entry_box,
            font=font_name,
            font_size=font_size,
            font_color=font_color,
            border_color=None,
            background_color=None,
        )
        annotations.append(annotation)
        writer.add_annotation(page_number=page_num - 1, annotation=annotation)
        
    with open(output_pdf_path, "wb") as output:
        writer.write(output)
    
    print(f"Successfully filled PDF form and saved to {output_pdf_path}")
    print(f"Added {len(annotations)} text annotations")


if __name__ == "__main__":
    if len(sys.argv) != 4:
        print("Usage: fill_pdf_form_with_annotations.py [input pdf] [fields.json] [output pdf]")
        sys.exit(1)
    input_pdf = sys.argv[1]
    fields_json = sys.argv[2]
    output_pdf = sys.argv[3]
    
    fill_pdf_form(input_pdf, fields_json, output_pdf)

```