Since 2013 all games have been migrated from HLDSUpdateTool to SteamCMD.
Note: HLDSUpdateTool was deprecated in early 2013 in favor of SteamCMD.
The Steam Console Client (SteamCMD) is a command-line version of the Steam client. It is used to install and update dedicated servers available on Steam.
You can download and use this tool for free.