Authentication Setup

The Gemini CLI requires you to authenticate with Google's AI services. On initial startup you'll need to configure one of the following authentication methods:

1. Login with Google (Gemini Code Assist):

   • Use this option to log in with your google account.

   • During initial startup, Gemini CLI will direct you to a webpage for authentication. Once authenticated, your credentials will be cached locally so the web login can be skipped on subsequent runs.

   • Note that the web login must be done in a browser that can communicate with the machine Gemini CLI is being run from. (Specifically, the browser will be redirected to a localhost url that Gemini CLI will be listening on).

   • Users may have to specify a GOOGLE_CLOUD_PROJECT if:

     1. You have a Google Workspace account. Google Workspace is a paid service for businesses and organizations that provides a suite of productivity tools, including a custom email domain (e.g. your-name@your-company.com), enhanced security features, and administrative controls. These accounts are often managed by an employer or school.
     2. You have received a free Code Assist license through the Google Developer Program (including qualified Google Developer Experts)
     3. You have been assigned a license to a current Gemini Code Assist standard or enterprise subscription.
     4. You are using the product outside the supported regions for free individual usage.>
     5. You are a Google account holder under the age of 18
     • If you fall into one of these categories, you must first configure a Google Cloud Project Id to use, enable the Gemini for Cloud API and configure access permissions.

     You can temporarily set the environment variable in your current shell session using the following command:

     export GOOGLE_CLOUD_PROJECT="YOUR_PROJECT_ID"

     • For repeated use, you can add the environment variable to your .env file (located in the project directory or user home directory) or your shell's configuration file (like ~/.bashrc, ~/.zshrc, or ~/.profile). For example, the following command adds the environment variable to a ~/.bashrc file:

     echo 'export GOOGLE_CLOUD_PROJECT="YOUR_PROJECT_ID"' >> ~/.bashrc
     source ~/.bashrc

2. Gemini API key:

   • Obtain your API key from Google AI Studio: https://aistudio.google.com/app/apikey
   • Set the GEMINI_API_KEY environment variable. In the following methods, replace YOUR_GEMINI_API_KEY with the API key you obtained from Google AI Studio:
     • You can temporarily set the environment variable in your current shell session using the following command:

       export GEMINI_API_KEY="YOUR_GEMINI_API_KEY"

     • For repeated use, you can add the environment variable to your .env file (located in the project directory or user home directory) or your shell's configuration file (like ~/.bashrc, ~/.zshrc, or ~/.profile). For example, the following command adds the environment variable to a ~/.bashrc file:

       echo 'export GEMINI_API_KEY="YOUR_GEMINI_API_KEY"' >> ~/.bashrc
       source ~/.bashrc

3. Vertex AI:

   • If not using express mode:
     • Ensure you have a Google Cloud project and have enabled the Vertex AI API.
     • Set up Application Default Credentials (ADC), using the following command:

       gcloud auth application-default login

       For more information, see Set up Application Default Credentials for Google Cloud.
     • Set the GOOGLE_CLOUD_PROJECT, GOOGLE_CLOUD_LOCATION, and GOOGLE_GENAI_USE_VERTEXAI environment variables. In the following methods, replace YOUR_PROJECT_ID and YOUR_PROJECT_LOCATION with the relevant values for your project:
       • You can temporarily set these environment variables in your current shell session using the following commands:

         export GOOGLE_CLOUD_PROJECT="YOUR_PROJECT_ID"
         export GOOGLE_CLOUD_LOCATION="YOUR_PROJECT_LOCATION" # e.g., us-central1
         export GOOGLE_GENAI_USE_VERTEXAI=true

       • For repeated use, you can add the environment variables to your .env file (located in the project directory or user home directory) or your shell's configuration file (like ~/.bashrc, ~/.zshrc, or ~/.profile). For example, the following commands add the environment variables to a ~/.bashrc file:

         echo 'export GOOGLE_CLOUD_PROJECT="YOUR_PROJECT_ID"' >> ~/.bashrc
         echo 'export GOOGLE_CLOUD_LOCATION="YOUR_PROJECT_LOCATION"' >> ~/.bashrc
         echo 'export GOOGLE_GENAI_USE_VERTEXAI=true' >> ~/.bashrc
         source ~/.bashrc

   • If using express mode:
     • Set the GOOGLE_API_KEY environment variable. In the following methods, replace YOUR_GOOGLE_API_KEY with your Vertex AI API key provided by express mode:
       • You can temporarily set these environment variables in your current shell session using the following commands:

         export GOOGLE_API_KEY="YOUR_GOOGLE_API_KEY"
         export GOOGLE_GENAI_USE_VERTEXAI=true

       • For repeated use, you can add the environment variables to your .env file (located in the project directory or user home directory) or your shell's configuration file (like ~/.bashrc, ~/.zshrc, or ~/.profile). For example, the following commands add the environment variables to a ~/.bashrc file:

         echo 'export GOOGLE_API_KEY="YOUR_GOOGLE_API_KEY"' >> ~/.bashrc
         echo 'export GOOGLE_GENAI_USE_VERTEXAI=true' >> ~/.bashrc
         source ~/.bashrc