Configure Your API Key

Once you have your Google AI API key, you need to configure it with Gemini CLI. Here are several methods to do so.

Method 1: Environment Variable (Recommended)

The most secure way is to set your API key as an environment variable:

For macOS/Linux:

# Add to ~/.bashrc, ~/.zshrc, or ~/.profile

export GEMINI_API_KEY="your-api-key-here"

# Reload your shell configuration

source ~/.bashrc # or ~/.zshrc

For Windows:

Option 1: Command Prompt (temporary)

set GEMINI_API_KEY=your-api-key-here

Option 2: PowerShell (temporary)

$env:GEMINI_API_KEY="your-api-key-here"

Option 3: System Environment Variables (permanent)

  1. Open System Properties → Advanced → Environment Variables
  2. Click "New" under User variables
  3. Variable name: GEMINI_API_KEY
  4. Variable value: your-api-key-here
  5. Click OK and restart your terminal

Method 2: Gemini Config Command

Use Gemini CLI's built-in configuration command:

gemini config set api-key YOUR_API_KEY

This stores your API key in a configuration file at ~/.gemini/config.json

Method 3: Configuration File

Create or edit the configuration file directly:

1. Create the config directory:

# macOS/Linux

mkdir -p ~/.gemini

# Windows

mkdir %USERPROFILE%\.gemini

2. Create config.json:

{ "apiKey": "your-api-key-here", "model": "gemini-pro", "temperature": 0.7, "maxTokens": 1000 }

Method 4: Per-Command API Key

You can also provide the API key for individual commands:

gemini --api-key YOUR_API_KEY "Your prompt here"

Warning: This method may expose your API key in shell history. Use environment variables or config files for better security.

Verify Your Configuration

Test that your API key is properly configured:

1. Check configuration:

gemini config show

2. Test with a simple command:

gemini "Hello, can you hear me?"

3. Check API status:

gemini status

Configuration Priority

Gemini CLI checks for API keys in this order:

  1. 1
    Command-line flag

    --api-key flag in the command

  2. 2
    Environment variable

    GEMINI_API_KEY environment variable

  3. 3
    Configuration file

    ~/.gemini/config.json

Troubleshooting

Error: API key not found

Make sure you've set the API key correctly:

# Check if environment variable is set

echo $GEMINI_API_KEY # macOS/Linux

echo %GEMINI_API_KEY% # Windows CMD

echo $env:GEMINI_API_KEY # Windows PowerShell

Error: Invalid API key

Verify that you've copied the entire key without any extra spaces or characters. Try regenerating a new key in Google AI Studio if the problem persists.

You're All Set!

Your API key is now configured. Start using Gemini CLI:

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