Source SDK Base

Source SDK Base is a game/tool, shared between all owners of Valve Source games and locked to a particular engine branch, on which modders can base their projects. Both singleplayer and multiplayer mods can use it.

The games that include SDK Base are listed here. Free copies available through hardware promotions do not provide access.

Contents

• The stock gamecode is a duplicate of Episode One's or Episode Two's, depending on which version (see below) you are using. But the only content available is that of Half-Life 2 and Half-Life 2: Lost Coast: while Zombines and Hunters exist in the code and can be spawned, they appear as errors because their models are not available. If you want to use episodic things, you will need to mount the appropriate game.
• SDK Base might provide mods with Lost Coast's content, but dedicated servers do not. Multiplayer mods should either not use anything from Lost Coast, or include what they do use in their dedicated server download.
  Tip:In Source 2007 or later you can remove the sourcetest SearchPath from gameinfo.txt and Lost Coast will disappear. Unfortunately, doing this under Source 2006 (Episode One) will make the game crash immediately!

Versions

There are currently two versions of SDK Base: the original Episode One / Source 2006 version (AppID 215) and the superior Source 2007 version (AppID 218).

There are separate builds because of the occasional break in Source's backwards compatibility. Unless you have a good reason for sticking with the an older version of the SDK Base, you should always use the most recent one available.

Content (2007)

• Source SDK Base 2007 (sourcetest)
• Source SDK Base (sourcetest)
• Half-Life 2: Lost Coast (lostcoast)
• Source 2007 shared (hl2)
• Source shared (hl2)
• Source 2007 engine branch

Content (2006)

• Source SDK Base (sourcetest)
• Half-Life 2: Lost Coast (lostcoast)
• Source shared (hl2)
• Episode One engine branch

FAQ

Where can I find Source SDK Base?

In Steam's Tools tab. You will be prompted to install it when first running a mod, or you can install it yourself. There is no need to run it directly.

Do I have to base my mod on Source SDK Base?

No, you can base on any game. But bear in mind that:

1. You are restricting the size of your audience if you require a specific purchase.
2. The game you rely on might be updated to an incompatible engine version and break your mod. This has happened several times over the years.

How can I use additional Steam content?

See Gameinfo.txt#Mounting content.