This tutorial will teach you how to use Gemini CLI to bring Google’s AI-powered coding assistance directly into your terminal. After you authenticate with your Google account, this tool will be ready to help you analyze code, identify bugs, and suggest fixes—all without leaving your familiar development environment:
Imagine debugging code without switching between your console and browser, or picture getting instant explanations for unfamiliar projects. Like other command-line AI assistants, Google’s Gemini CLI brings AI-powered coding assistance directly into your command line, allowing you to stay focused in your development workflow.
Whether you’re troubleshooting a stubborn bug, understanding legacy code, or generating documentation, this tool acts as an intelligent pair-programming partner that understands your codebase’s context.
You’re about to install Gemini CLI, authenticate with Google’s free tier, and put it to work on an actual Python project. You’ll discover how natural language queries can help you understand code faster and catch bugs that might slip past manual review.
Prerequisites
To follow along with this tutorial, you’ll need the following:
- Google Account: A personal Google account is required to use Gemini CLI’s free tier, which offers one thousand requests per day and sixty requests per minute at no charge.
- Python 3.12 or Higher: You’ll work with a Python command-line application to demonstrate Gemini CLI’s capabilities. If you haven’t already, install Python on your system, making sure the minimum version is Python 3.12.
- Node.js 20 or Higher: Gemini CLI is distributed through npm, Node.js’s package manager. You’ll verify your Node.js installation in the next section.
Because Gemini CLI is a command-line tool, you should feel comfortable navigating your terminal and running basic shell commands.
Go ahead and download the supporting materials to get the Python project you’ll be working with throughout this tutorial:
Get Your Code: Click here to download the free sample code that you’ll use to take Google’s Gemini CLI for a spin.
Once you’ve extracted the files, you’ll find a todolist/ directory containing a complete Python CLI application, which is similar to the to-do app covered in another tutorial. This project will serve as your testing ground for Gemini CLI’s code analysis and debugging features.
Take the Quiz: Test your knowledge with our interactive “How to Use Google's Gemini CLI for AI Code Assistance” quiz. You’ll receive a score upon completion to help you track your learning progress:
Interactive Quiz
How to Use Google's Gemini CLI for AI Code AssistanceLearn how to install, authenticate, and safely use the Gemini CLI to interact with Google's Gemini models.
Step 1: Install and Set Up Gemini CLI
Before you can start using the AI-powered features of Gemini CLI, you need to get it installed on your system and authenticate with Google. In this step, you’ll verify your Node.js installation, install Gemini CLI globally, and complete the authentication process to access the free tier.
Verify Your Node.js Installation
Gemini CLI is primarily implemented in TypeScript, which requires Node.js. You’ll need Node.js version 20 or higher to run Gemini CLI. First, check if you have Node.js installed in the required version by opening your terminal and running this command:
$ node --version
v24.11.1
If you see a version number of 20 or higher, then you’re all set. Otherwise, if you encounter a command not found error or have an older version, then you’ll need to install or update Node.js before continuing.
Note: If you’re on macOS or Linux, then you can leverage Homebrew to get Gemini CLI without having to install Node.js yourself.
The recommended approach to install Node.js is to use the Node Version Manager (nvm), which allows you to install and switch between multiple Node.js versions, much like pyenv does for Python. You can find detailed installation instructions for your operating system on the Node.js download page.
Once Node.js is installed, you’ll also have access to the Node Package Manager (npm), which you’ll use in the next step.
Install Gemini CLI Globally
With Node.js installed, you can now install Gemini CLI using npm. The -g flag installs the package globally, making the gemini command available from anywhere in your file system:
$ npm install -g @google/gemini-cli
