The HTTP tags available in DTF will always respond with HTTP codes from the server side that the server has sent back. These tags will also generate certain client side codes using the 9XX range of codes to signal common errors on the client side. Here is the list of codes and their description:

• 900 - Connection error (connection refused)
• 901 - Socket error (broken pipe, socket reset)
• 902 - Unknown host (dns resolution error, bad hostname)
• 903 - Connection timeout error
• 999 - Unknown client error