This is the model tree for TF2 Panda, containing all of the models, textures, sounds, etc, in source form. It uses a Makefile-based pipeline to export, compile, and install all of the assets.
All of the prop models and materials were converted from Source using an automated script, while most dynamic gameplay models (characters, buildings, etc) were converted by hand.
The game code is stored in a separate repository: tf
Building this repository requires a developer build of the engine and having the necessary tools installed. More information about that is available in the tf repository.