Guide to AI Coding Agents & Assistants: How to Choose the Right One. There are now so many AI tools for coding that it can be confusing to know which one to pick. Some act as simple helpers (Assistant), while others can do the work for you (Agent). This guide breaks down the top AI coding tools that you should be aware of. We will look at what they do, who they are for, and how much they cost. Gemini Code Assist uses the Gemini models to provide context-aware completions, generate full functions or files, write unit tests and debug code within IDEs like VS Code and JetBrains.