gh-jhs-chatfield-claude-filling-pdf-forms/skills/extracting-form-fields/SKILL.md

name, description, allowed-tools, version, license

name	description	allowed-tools	version	license
extracting-form-fields	Extract form field data from PDFs as a first step to filling PDF forms	Read, Write, Edit, Glob, Bash	1.0.0a2	Apache 2.0

Extracting Form Fields

Prepare working directory and extract field data from PDF forms.

This skill extracts PDF form information into useful JSON. - Detects fillable vs. non-fillable PDFs - Extracts PDF content as readable Markdown - Creates field metadata in common JSON format

Inputs

• PDF path: Path to PDF file (e.g., /home/user/input.pdf)

Process Overview

@startuml SKILL
title Extracting Form Fields - High-Level Workflow
start
:Create working directory;
:Copy interview template;
:Extract PDF content as Markdown;
:Check Fillability;
if (PDF has fillable fields?) then (yes)
  :Fillable workflow
  (see Fillable-Forms.md);
else (no)
  :Non-fillable workflow
  (see Nonfillable-Forms.md);
endif
:**✓ EXTRACTION COMPLETE**;
:Ready for Form Data Model creation;
stop
@enduml

Process

1. Create Working Directory

mkdir <basename>.chatfield

2. Copy Interview Template

Copy a file from the included filling-pdf-forms skill's template. The example path below is relative to this skill directory.

cp ../filling-pdf-forms/scripts/chatfield_interview_template.py <basename>.chatfield/interview.py

3. Extract PDF Content

markitdown <pdf_path> > <basename>.chatfield/<basename>.form.md

4. Check Fillability

python scripts/check_fillable_fields.py <pdf_path>

Output:

• "This PDF has fillable form fields" → use fillable workflow
• "This PDF does not have fillable form fields" → use non-fillable workflow

5. Branch Based on Fillability

If Fillable:

Follow ./references/Fillable-Forms.md

If Non-fillable:

Follow ./references/Nonfillable-Forms.md

Output Format

Fillable PDFs - .form.json

[
  {
    "field_id": "topmostSubform[0].Page1[0].f1_01[0]",
    "type": "text",
    "page": 1,
    "rect": [100, 200, 300, 220],
    "tooltip": "Enter your full legal name",
    "max_length": null
  },
  {
    "field_id": "checkbox_over_18",
    "type": "checkbox",
    "page": 1,
    "rect": [150, 250, 165, 265],
    "checked_value": "/1",
    "unchecked_value": "/Off"
  }
]

References

• ./references/Fillable-Forms.md - Fillable PDF extraction workflow
• ./references/Nonfillable-Forms.md - Non-fillable PDF extraction workflow