The official tool kit used to create Rage and its downloadable content The Scorchers will be available on Steam, id Software announced on the Bethesda Blog.
The studio included a FAQ for troubleshooting and a brief introduction for those interested in the kit, which "should not be interpreted as consumer ready." Its tools are complex and aimed at those with a previous understanding of modding. Tutorials, maps and game assets are included.
The kit begins at 35 GB, though with recommended additions and creations it will expand.
The Rage Tool Kit will available in Steam's Tools section.