Gemini CLI — Getting Started (Enterprise)

Gemini CLI is Google's enterprise terminal-based AI coding agent for Vertex AI customers, with a 1M+ token context window. It runs the Gemini 2.5 Pro model, integrates with Google's ecosystem (Drive, Gmail, Calendar), and supports sandboxed execution for safer autonomous coding. Note that Gemini CLI has been deprecated for individual consumers in favor of Google Antigravity.

Enterprise Installation

Gemini CLI is available to Vertex AI customers. Contact your Google Cloud account team for access.

# Via npm (enterprise only)
npm install -g @google/gemini-cli

# Verify
gemini --version

Authentication (Vertex AI)

Enterprise authentication uses Google Cloud service accounts:

# Authenticate via Google Cloud
gcloud auth application-default login

# Set your project
gcloud config set project YOUR_PROJECT_ID

# Verify auth
gemini auth status

For non-interactive environments (CI/CD):

# Set up a service account at console.cloud.google.com
export GOOGLE_APPLICATION_CREDENTIALS="/path/to/service-account.json"
gcloud auth application-default login

Sandbox Modes

Gemini CLI runs commands in configurable sandboxes to prevent unintended changes:

Set the default mode:

# In gemini.yaml
sandbox:
  mode: workspace
  allowedDirectories:
    - ./src
    - ./lib
    - ./public

First Session

cd my-project
gemini

First-start experience:

⚡ Welcome to Gemini CLI
  Model: gemini-2.5-pro
  Context: 1,048,576 tokens
  Sandbox: workspace (project directory)
  
  Type /help for commands.
  
>

Essential Slash Commands

Project Configuration: GEMINI.md

Create GEMINI.md (or .gemini/GEMINI.md) at project root:

# GEMINI.md

## Commands
- `npm run dev` — Start dev server
- `npm run build` — Production build
- `npm run test` — Vitest test suite
- `npm run lint` — ESLint + TypeScript

## Architecture
- Vite + React 19 with React Router v7
- Zustand for client state, React Query for server state
- Tailwind CSS v4 with custom design tokens

## Sandbox Rules
- Keep sandbox at `workspace` — never switch to `full`
- Allowed directories: src/, lib/, tests/, public/
- Blocked: node_modules/, .env, dist/

## Google Integration
- Google Drive folder: team/docs/shared — read only
- Google Calendar: check before scheduling changes

Google Ecosystem Integration

Gemini CLI connects to Google services via extensions:

# Enable extensions
gemini extensions enable google-drive
gemini extensions enable google-calendar
gemini extensions enable gmail

Then in prompts:

> Read the design spec from Google Drive (team/docs/specs/v2.md) 
  and compare it with our current implementation in src/components/.
  List gaps.

Context Window Advantage

With 1M tokens, Gemini CLI can hold your entire codebase in context. Use this for:

• Full codebase analysis — "Find every place we use localStorage and assess whether it should be sessionStorage"
• Cross-cutting refactors — "Rename User to Account across the entire codebase and update all references"
• Documentation generation — "Read every API route and generate OpenAPI specs"

Related Pages

• Prompt Engineering in Gemini CLI — Ralph loop, extensions, prompt patterns
• Gemini CLI Configuration — gemini.yaml, MCP, .gemini/ conventions
• Tool Comparison — Gemini CLI vs Claude Code vs OpenCode vs Cursor vs Copilot
• Mastering Gemini CLI (Blog) — Comprehensive Gemini CLI guide with sandboxing and CI/CD