Installing Gemini CLI and writing GEMINI.md: getting started with a free Google account

Gemini CLI is Google's open-source coding agent for the terminal. Its standout feature is that a personal Google account is enough to start using it for free, within rate limits.

This article walks through installation, sign-in and the first task, then explains GEMINI.md, the file that tells Gemini CLI about your project.

Requirements

Item	Detail
Node.js	20 or later
OS	macOS, Linux, Windows
Account	Personal Google account (free tier), a Gemini API key, or Google Cloud (Vertex AI)

Installation

# global install with npm
npm install -g @google/gemini-cli

# or Homebrew on macOS
brew install gemini-cli

# or try it without installing
npx @google/gemini-cli

gemini --version

Signing in

Run gemini in your project directory. The first start asks how you want to authenticate.

cd path/to/project
gemini

Method	Notes
Google account	Browser sign-in. A personal account gets the free tier
Gemini API key	Issued in Google AI Studio; set GEMINI_API_KEY
Vertex AI	Through a Google Cloud project; for organizations

# using an API key
export GEMINI_API_KEY="your-key"

First task

Explain the structure of this repository and how to run the tests

Gemini CLI reads files and runs commands as needed, asking before it changes files or executes commands. Choosing "always allow" skips the prompt for that kind of action for the rest of the session.

Useful commands during a session:

Command	What it does
/help	List commands
/memory show	Show the loaded GEMINI.md content
/memory refresh	Reload GEMINI.md
/tools	List available tools
/mcp	MCP server status
/stats	Token usage
/clear	Clear the screen and history

GEMINI.md: role and locations

Gemini CLI looks for GEMINI.md at start-up and treats it as project context, the same role CLAUDE.md plays for Claude Code and AGENTS.md for Codex.

Location	Purpose
~/.gemini/GEMINI.md	Personal preferences for all projects
GEMINI.md at the repository root	Shared project rules
GEMINI.md in a subdirectory	Extra rules loaded when working in that directory

The files are concatenated; /memory show displays the result.

A GEMINI.md template

# Project overview
Django + React internal tool. Backend in `backend/`, frontend in `frontend/`.

## Commands
- Backend tests: `cd backend && pytest`
- Frontend tests: `cd frontend && npm test`
- Lint: `cd backend && ruff check .` / `cd frontend && npm run lint`
- Dev server: `docker compose up`

## Conventions
- Python: type hints required; no `Any`
- React: function components only; use the existing Zustand store for state
- API schemas live in `backend/api/schemas/`; regenerate frontend types with the generator

## Do not modify
- Existing files under `backend/migrations/`
- `frontend/src/generated/`

## Workflow
- Read related tests before changing code
- Present a plan before changes spanning several files
- Include the commands you ran and their results in the completion report

/init generates a first draft from the project. Trim anything the README already says and keep only the agreements you cannot see in the code, the same approach as in How to write CLAUDE.md.

Saving notes during a session

/memory add <text> appends the text to your user-level GEMINI.md. Anything you keep repeating is worth saving this way so it carries over to the next session.

Summary

• Install with npm install -g @google/gemini-cli, run gemini, sign in with a Google account
• GEMINI.md is merged from ~/.gemini/, the repository root and subdirectories
• Check what is loaded with /memory show; reload with /memory refresh
• Generate a draft with /init, then keep it to commands, conventions, no-go areas and workflow