Environment Variables Setup

Configure Gemini CLI using environment variables for secure and flexible configuration management.

Why Use Environment Variables?

  • Security: Keep sensitive data like API keys out of your code
  • Flexibility: Different settings for development, staging, and production
  • Portability: Works across different systems and deployment environments
  • Team Collaboration: Each team member can have their own configuration

Core Environment Variables

GOOGLE_AI_API_KEY

Your Google AI API key for authentication

export GOOGLE_AI_API_KEY="AIza..."

Required for all Gemini CLI operations.Get your API key →

GEMINI_MODEL

Default model to use for requests

export GEMINI_MODEL="gemini-pro"

# or gemini-pro-vision, gemini-ultra

GEMINI_TEMPERATURE

Control randomness in responses (0.0 to 1.0)

export GEMINI_TEMPERATURE="0.7"

# 0.0 = deterministic, 1.0 = creative

GEMINI_MAX_TOKENS

Maximum tokens in response

export GEMINI_MAX_TOKENS="2048"

GEMINI_CONFIG_PATH

Custom path for configuration file

export GEMINI_CONFIG_PATH="/path/to/your/config.json"

Platform-Specific Setup

🐧Linux

Temporary (current session):

export GOOGLE_AI_API_KEY="your-key"

Permanent (bash):

echo 'export GOOGLE_AI_API_KEY="your-key"' >> ~/.bashrc

source ~/.bashrc

🍎macOS

Temporary:

export GOOGLE_AI_API_KEY="your-key"

Permanent (zsh):

echo 'export GOOGLE_AI_API_KEY="your-key"' >> ~/.zshrc

source ~/.zshrc

🪟Windows

Command Prompt:

set GOOGLE_AI_API_KEY=your-key

PowerShell:

$env:GOOGLE_AI_API_KEY="your-key"

Permanent: System Properties → Environment Variables

Using .env Files

For project-specific configuration, use .env files:

1. Create .env file:

# .env

GOOGLE_AI_API_KEY=your-api-key-here

GEMINI_MODEL=gemini-pro

GEMINI_TEMPERATURE=0.7

GEMINI_MAX_TOKENS=2048

2. Load .env file:

# Load environment variables from .env

set -a && source .env && set +a

Important: Add .env to your .gitignore file to avoid committing sensitive data to version control.

Verify Your Setup

Check if variables are set:

# Unix/Linux/macOS

echo $GOOGLE_AI_API_KEY

env | grep GEMINI

# Windows

echo %GOOGLE_AI_API_KEY%

Test Gemini CLI with environment variables:

gemini "Hello, world!"

Best Practices

✅ Do

  • • Use different API keys for different environments
  • • Keep API keys in environment variables, not in code
  • • Use .env files for local development
  • • Document required environment variables
  • • Use validation scripts to check setup

❌ Don't

  • • Commit .env files to version control
  • • Share API keys in chat or email
  • • Use production keys in development
  • • Hardcode sensitive values in scripts
  • • Ignore environment variable validation

Next Steps

Now that you have environment variables set up, configure your API key: