Visual Studio 2008 SDK Version 1.0
The Visual Studio 2008 Software Development Kit SDK 1.0 includes tools, documentation, and samples for developers to design, build, test and deploy extensions for Visual Studio 2008. You can also use the VS 2008 SDK 1.0 to create custom tools environments based on the Visual Studio 2008 Shell.
Before starting your project get more information and news about Visual Studio Extensibility VSX, at the VSX Developer Center and on the VSX Team Blog .