PDF Content Extraction and Analysis

Key Principles

• Preserve the logical structure of the document: headings, sections, lists, and table relationships.
• When extracting data, maintain the original ordering and hierarchy unless the user requests a different organization.
• Clearly distinguish between exact text extraction and your interpretation or summary.
• Flag any content that could not be extracted reliably (e.g., scanned images without OCR, corrupted sections).

Extraction Techniques

• For text-based PDFs, extract content while preserving paragraph boundaries and section headings.
• For scanned PDFs, use OCR tools (

  tesseract

  ,

  pdf2image

  + OCR, or cloud OCR APIs) and note the confidence level.
• For tables, reconstruct the row/column structure. Present tables in Markdown format or as structured data (CSV/JSON).
• For forms, extract field labels and their filled values as key-value pairs.
• For multi-column layouts, identify column boundaries and read content in the correct order.

Analysis Patterns

• Summarization: Provide a hierarchical summary — one-line overview, then section-by-section breakdown.
• Data extraction: Pull specific data points (dates, amounts, names, addresses) into structured formats.
• Comparison: When comparing multiple PDFs, align them by section or topic and highlight differences.
• Search: Locate specific information by keyword, page number, or section heading.
• Metadata: Extract document properties — author, creation date, page count, PDF version, embedded fonts.

Handling Complex Documents

• Legal documents: identify parties, key dates, obligations, and defined terms.
• Financial reports: extract tables, charts data, key metrics, and footnotes.
• Academic papers: identify abstract, methodology, results, conclusions, and references.
• Invoices/receipts: extract line items, totals, tax amounts, vendor info, and payment terms.

Output Formats

• Markdown for readable summaries with preserved structure.
• JSON for structured data extraction (tables, forms, metadata).
• CSV for tabular data that will be processed further.
• Plain text for simple content extraction.

Pitfalls to Avoid

• Do not assume all text in a PDF is selectable — some documents are scanned images.
• Do not ignore headers, footers, and page numbers that may interfere with content flow.
• Do not merge table cells incorrectly — verify row/column alignment before presenting extracted tables.
• Do not skip footnotes or appendices unless the user explicitly requests only the main body.