How to Install Gemini CLI on Termux

Welcome to Rebooted X! Ever wanted to harness the power of Google's advanced AI models directly from a command line on your Android device? This guide makes it possible. We will walk you through installing and configuring the Gemini CLI (Command-Line Interface) within Termux, turning your Android phone into a powerful AI interaction tool.

This guide is perfect for developers, scripters, and tech enthusiasts who want to generate content, automate tasks, or simply explore the capabilities of Google's Gemini models from anywhere.

Guide Contents

First, What is Termux?

For those new to the scene, Termux is a powerful terminal emulator and Linux environment for Android. It allows you to install and run a huge variety of command-line tools and programming languages directly on your phone, without needing to root your device. It's a must-have for any Android power user.

Prerequisites

Before we begin, ensure you have the following:

Termux App Installed: Download and install Termux from a reliable source like F-Droid.
A Gemini API Key: This is a free key you can get from Google AI Studio.
A Stable Internet Connection: Required for downloading packages.

Installation and Setup

This section covers the core installation of the Gemini CLI and its dependencies.

Step 1: Update Termux Packages

First, it's crucial to update and upgrade all the core packages in your Termux environment. This prevents compatibility issues and ensures you have the latest security patches.

pkg update && pkg upgrade -y

Step 2: Install Node.js and npm

The Gemini CLI is built on Node.js, a JavaScript runtime environment. We need to install it along with its package manager, npm (Node Package Manager), which will handle the installation of the CLI itself.

pkg install nodejs -y

Step 3: Install the Gemini CLI

Now, we will use npm to install the Gemini CLI globally. The `-g` flag makes it available as a command throughout your Termux session. The `--unsafe-perm=true` flag is often required to avoid permission issues when installing global packages in the Termux environment.

npm install -g @google/gemini-cli --unsafe-perm=true

Authenticating Your API Key

The CLI needs your unique API key to communicate with Google's Gemini models.

Step 4: Get Your Gemini API Key

If you don't have one already, open your web browser and go to the Google AI Studio to get your key. It's a simple process.

Visit aistudio.google.com/app/apikey.
Click on "Create API key in new project" or copy an existing key.
Important: Keep this key safe and do not share it publicly. Treat it like a password.

Step 5: Set the API Key in Termux

You need to set an environment variable so the CLI knows where to find your key. You have two options for this.

Option A – Temporary (Current Session Only)
This method is great for a quick test. The key will be forgotten as soon as you close your Termux session.

export GEMINI_API_KEY="your_api_key_here"

Option B – Permanent (Recommended)
This method automatically loads your API key every time you start Termux. It saves the key to your shell's startup file (`.bashrc` for the default Bash shell).

First, run this command to add the key to your configuration file. Make sure to replace "your_api_key_here" with your actual key.

echo 'export GEMINI_API_KEY="your_api_key_here"' >> ~/.bashrc

Then, reload the shell to apply the changes immediately:

source ~/.bashrc

Verifying the Installation and Basic Usage

Step 6: Run Gemini CLI

To verify that everything is working, simply type `gemini` and press Enter. If you see a list of available commands and options, the installation was successful.

gemini

Basic Usage Examples

Here are a few simple commands to get you started:

Generate text from a prompt:

gemini prompt "Write a short poem about Android and Termux"

Start an interactive chat session:

gemini chat

Troubleshooting

'gemini: command not found' Error

This is a common issue where the shell doesn't know where the `gemini` command was installed. You need to add its location to your system's PATH variable.

1. First, find out where npm installs global modules:

npm config get prefix

2. The output will be a path, like `/data/data/com.termux/files/usr`. The executables are usually in a `/bin` subfolder inside this path.

3. Add this path to your shell's startup file. Make sure to replace the path with the one you got from the command above.

echo 'export PATH=$PATH:/data/data/com.termux/files/usr/bin' >> ~/.bashrc

4. Reload your shell to apply the changes:

source ~/.bashrc

You're now ready to use the Gemini CLI on Termux to generate content, automate tasks, write code, and explore the vast world of AI tools — all from the palm of your hand!