# PDF MCP Extension Development Brief
## Project Overview
Build an MCP (Model Context Protocol) extension that provides a toolkit for AI agents to work dynamically with PDF files. Current PDF handling ingests entire documents, wasting tokens. This extension enables selective, on-demand content extraction.
## Core Features (Priority 1)
### PDF Metadata Tool
- Number of pages
- File size
- Creation/modification dates
- Author, title, subject metadata
- PDF version info
### Persistent Scratchpad Tool
- Create/edit local scratchpad file in PDF folder
- Markdown format
- Persistent notes about PDF content
- Session memory across interactions
### Text Extraction Tool
- Extract text from page ranges (e.g., pages 5-10)
- Single page extraction
- Configurable formatting options
### Image Extraction Tool
- Extract page ranges as images
- Configurable format (PNG/JPEG) and quality
- Single page extraction
### Combined Extraction Tool
- Get both text and images for specified pages
- Synchronized text-image pairs
## Enhanced Features (Priority 2)
### Search Tool
- Find pages containing keywords/phrases
- Return page numbers and snippets
### Structure Extraction Tools
- Table of contents extraction
- Bookmark/outline extraction
- Page classification (title, TOC, references, figures)
### Selective Extraction Tools
- Extract from specific coordinates/regions
- Form field extraction
- Annotation extraction (comments, highlights)
### Analysis Tools
- Text density analysis per page
- Language detection
- Figure/table detection
## Technical Requirements
### MCP Implementation
- Follow MCP protocol specification
- Proper tool definitions with parameters
- Error handling and status codes
- JSON-based communication
### File Handling
- Support common PDF formats
- Handle corrupted/complex PDFs gracefully
- Local file storage for scratchpad
- Efficient memory usage for large files
### Dependencies
- PDF parsing library (PyPDF2, pdfplumber, or pymupdf)
- Image processing capabilities
- Text extraction with formatting preservation
- Coordinate-based region extraction
### Error Handling
- Invalid page ranges
- Corrupted PDF files
- Missing files
- Permission errors
- Memory limitations
### Performance
- Lazy loading - only process requested content
- Cache frequently accessed pages
- Minimize token usage through selective extraction
- Handle large PDFs without memory issues
