PDF Manipulation MCP Server

Instructions

Implementation Reference

• pdf_manipulation_mcp_server/pdf_server.py:397-452 (handler)

  The handler function for the 'pdf_fill_form' tool. It takes a PDF path and a dictionary of field_values, opens the PDF using PyMuPDF, iterates through all form widgets across pages, sets the corresponding field values based on widget type, and saves the updated PDF to a new timestamped file.
  @mcp.tool() async def pdf_fill_form( pdf_path: str, field_values: Dict[str, Any] ) -> str: """Fill form fields in a PDF with values.""" if not os.path.exists(pdf_path): return f"Error: PDF file not found: {pdf_path}" if not validate_pdf_file(pdf_path): return f"Error: Invalid PDF file: {pdf_path}" try: # Open PDF document doc = fitz.open(pdf_path) filled_fields = 0 # Fill form fields for page_num in range(len(doc)): page = doc[page_num] widgets = page.widgets() for widget in widgets: field_name = widget.field_name if field_name in field_values: value = field_values[field_name] # Set field value based on widget type if widget.field_type == fitz.PDF_WIDGET_TYPE_TEXT: widget.field_value = str(value) elif widget.field_type == fitz.PDF_WIDGET_TYPE_CHECKBOX: widget.field_value = bool(value) elif widget.field_type == fitz.PDF_WIDGET_TYPE_RADIOBUTTON: widget.field_value = str(value) elif widget.field_type == fitz.PDF_WIDGET_TYPE_COMBOBOX: widget.field_value = str(value) widget.update() filled_fields += 1 if filled_fields == 0: doc.close() return "No matching form fields found to fill." # Generate output filename output_path = generate_output_filename(pdf_path) # Save the modified PDF doc.save(output_path) doc.close() return f"Successfully filled {filled_fields} form fields. Output saved to: {output_path}" except Exception as e: return f"Error filling form fields: {str(e)}"
• pdf_manipulation_mcp_server/pdf_server.py:397-397 (registration)

  The @mcp.tool() decorator registers the pdf_fill_form function as an MCP tool with FastMCP, automatically generating the input schema from the function signature.
  @mcp.tool()
• pdf_manipulation_mcp_server/pdf_server.py:28-36 (helper)

  Helper function used by pdf_fill_form to validate the input PDF file.
  def validate_pdf_file(pdf_path: str) -> bool: """Validate that the file is a valid PDF.""" try: doc = fitz.open(pdf_path) doc.close() return True except Exception: return False
• pdf_manipulation_mcp_server/pdf_server.py:22-27 (helper)

  Helper function used by pdf_fill_form to generate a timestamped output filename.
  def generate_output_filename(input_path: str, suffix: str = "modified") -> str: """Generate a new filename with timestamp to avoid overwriting originals.""" path = Path(input_path) timestamp = datetime.now().strftime("%Y%m%d_%H%M%S") return str(path.parent / f"{path.stem}_{suffix}_{timestamp}{path.suffix}")
• pdf_manipulation_mcp_server/pdf_server.py:398-402 (schema)

  Input schema defined by function parameters: pdf_path (str) - path to the PDF file; field_values (Dict[str, Any]) - dictionary mapping field names to their values.
  async def pdf_fill_form( pdf_path: str, field_values: Dict[str, Any] ) -> str: """Fill form fields in a PDF with values."""