Tavily Web Search MCP Server

Instructions

Implementation Reference

• server.py:137-186 (handler)

  The main handler function for the 'generate_qr_code' tool, decorated with @mcp.tool() which also registers it in the MCP server. It generates a QR code from input data using the qrcode library, applies specified error correction, border, and box size, and returns a base64-encoded PNG image.

  @mcp.tool()
  def generate_qr_code(data: str, error_correction: str = "M", border: int = 4, box_size: int = 10) -> str:
      """
      Generate a QR code for the given data.
      
      Args:
          data: The text or URL to encode in the QR code
          error_correction: Error correction level - "L" (Low ~7%), "M" (Medium ~15%), "Q" (Quartile ~25%), "H" (High ~30%)
          border: Size of the border (minimum is 4)
          box_size: Size of each box in pixels (default 10)
      
      Returns:
          Base64 encoded PNG image of the QR code that can be displayed or saved
      """
      try:
          # Set error correction level
          error_levels = {
              "L": qrcode.constants.ERROR_CORRECT_L,
              "M": qrcode.constants.ERROR_CORRECT_M, 
              "Q": qrcode.constants.ERROR_CORRECT_Q,
              "H": qrcode.constants.ERROR_CORRECT_H
          }
          
          if error_correction not in error_levels:
              return f"Error: Invalid error correction level. Use L, M, Q, or H"
          
          # Create QR code instance
          qr = qrcode.QRCode(
              version=1,  # Controls size (1 is smallest)
              error_correction=error_levels[error_correction],
              box_size=box_size,
              border=max(border, 4),  # Minimum border is 4
          )
          
          # Add data
          qr.add_data(data)
          qr.make(fit=True)
          
          # Create image
          img = qr.make_image(fill_color="black", back_color="white")
          
          # Convert to base64 for easy transmission
          img_buffer = io.BytesIO()
          img.save(img_buffer, format='PNG')
          img_str = base64.b64encode(img_buffer.getvalue()).decode()
          
          return f"QR code generated successfully for: '{data[:50]}{'...' if len(data) > 50 else ''}'\nBase64 PNG: data:image/png;base64,{img_str}"
          
      except Exception as e:
          return f"Error generating QR code: {str(e)}"