Plugin For Source.Python
This plugin is meant to paint a set of predefined decals/materials onto the active level without modifying the bsp.
It's mainly handy to customize a map a bit to your own server/community without actually editing the map.
There is an example included which paints some standard CSS decals @ CT spawn on de_dust2, but it fully supports and makes your own materials downloadable, which is it's intended use.
Forum Topic: https://forums.sourcepython.com/viewtopic.php?f=7&t=565