From Valve Developer Community
- MDL Texture Info
- A console utility that lists all the materials used in a MDL.
- A tool for decompiling .MDL files and making new ones (Also see: Crowbar)
- Breaks MDL files down to their component parts.
- A tool to convert TGA to VTF, and back again.
- Photoshop VTF Plugin
- A plugin for photoshop that can both open and save VTF files.
- An open source (free) 3D modeling package that can be used to create static and physics props.