Valve has recently released the “Source SDK 2013” tools, designed for creating mods for games that use the Source engine. This release is particularly noteworthy as it includes the game codes for popular titles such as Half-Life 2, Half-Life 2: Deathmatch, and Team Fortress 2. The Source SDK 2013 package supports both Linux and Windows platforms.
The code for Source SDK 2013 can be found on Valve’s GitHub page, distributed under the Source 1 SDK license. This license allows users to freely use, copy, and modify the code, as long as the resulting modifications are shared for free and do not violate Steam’s terms of service.
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