PDF Tools MCP Server

Instructions

Supports both local file paths and URLs. URLs will be downloaded to temporary
files before merging. Mixed local and URL paths are supported.

Args:
    pdf_paths: List of paths to PDF files to merge (in order) - can include URLs
    output_path: Path where the merged PDF will be saved (must be local path)
    
Returns:
    Success message with merge details or error message

Implementation Reference

• pdf_tools_mcp/server.py:483-548 (handler)

  Implementation of the merge_pdfs MCP tool, which resolves input paths (including URLs), validates the output path, and merges PDFs using PyPDF2.

  async def merge_pdfs(pdf_paths: List[str], output_path: str) -> str:
      """Merge multiple PDF files into one.
      
      Supports both local file paths and URLs. URLs will be downloaded to temporary
      files before merging. Mixed local and URL paths are supported.
  
      Args:
          pdf_paths: List of paths to PDF files to merge (in order) - can include URLs
          output_path: Path where the merged PDF will be saved (must be local path)
          
      Returns:
          Success message with merge details or error message
      """
      # Resolve all input paths (download URLs if needed)
      actual_paths = []
      for pdf_path in pdf_paths:
          try:
              actual_path = resolve_path(pdf_path)
              
              # Validate local path if not URL
              if not is_url(pdf_path):
                  is_valid, error_msg = validate_path(pdf_path)
                  if not is_valid:
                      return error_msg
              
              actual_paths.append(actual_path)
              
          except Exception as e:
              return f"Error resolving path '{pdf_path}': {str(e)}"
      
      # Validate output path (must be local)
      if is_url(output_path):
          return "Error: Output path cannot be a URL, must be a local file path"
      
      is_valid, error_msg = validate_path(output_path)
      if not is_valid:
          return error_msg
      
      try:
          pdf_writer = PyPDF2.PdfWriter()
          total_pages_merged = 0
          
          for i, actual_path in enumerate(actual_paths):
              original_path = pdf_paths[i]
              try:
                  with open(actual_path, 'rb') as pdf_file:
                      pdf_reader = PyPDF2.PdfReader(pdf_file)
                      pages_count = len(pdf_reader.pages)
                      
                      for page in pdf_reader.pages:
                          pdf_writer.add_page(page)
                      
                      total_pages_merged += pages_count
                      logging.info(f"Added {pages_count} pages from {original_path}")
              
              except Exception as e:
                  return f"Error reading PDF '{original_path}': {str(e)}"
          
          # Write the merged PDF
          with open(output_path, 'wb') as output_file:
              pdf_writer.write(output_file)
          
          return f"Successfully merged {len(pdf_paths)} PDFs into '{output_path}'\nTotal pages: {total_pages_merged}"
          
      except Exception as e:
          return f"Error merging PDFs: {str(e)}"