Configuration

Configuration

Settings, environment variables, and model selection for Gemini CLI with Google Ads commands.

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Project Settings

File: .gemini/settings.json

{
  "experimental": {
    "plan": true,
    "extensionReloading": true,
    "modelSteering": true
  },
  "general": {
    "devtools": true
  }
}

Setting	What It Does
experimental.plan	Enables /plan command for multi-step task planning
experimental.extensionReloading	Hot-reloads extensions during development
experimental.modelSteering	Allows model to select sub-models for specific tasks
general.devtools	Enables the developer tools panel

Environment Variables

Authentication

Variable	Description	Required
GEMINI_API_KEY	AI Studio API key (from aistudio.google.com/apikey)	For API key auth
GOOGLE_API_KEY	Google Cloud API key	For Vertex AI
GOOGLE_GENAI_USE_VERTEXAI	Set true to use Vertex AI backend	For Vertex AI
GOOGLE_CLOUD_PROJECT	GCP project ID	For Code Assist / Workspace
GOOGLE_APPLICATION_CREDENTIALS	Path to service account JSON	For service account auth

CLI Behavior

Variable	Description	Default
GEMINI_MODEL	Override default model (e.g., gemini-2.5-flash)	Auto (Gemini 3)
GEMINI_CLI_HOME	Override user config directory	~/.gemini
GEMINI_SANDBOX	Sandbox mode: true, false, docker, podman	false

File Locations

File	Scope	Purpose
~/.gemini/settings.json	User (all projects)	Global settings
.gemini/settings.json	Project	Project-specific settings
.gemini/commands/*.toml	Project	Custom slash commands
.gemini/skills/*/skill.md	Project	Agent skills (auto-loaded)
GEMINI.md	Project	Project context file read on startup
.gemini/.env	Project	Environment variables (loaded automatically)

Model Selection

# Use a specific model via CLI flag
gemini -m gemini-2.5-flash

# Or set via environment variable
export GEMINI_MODEL="gemini-2.5-flash"

# Or use the /model command inside the prompt
/model gemini-2.5-pro

Available Models

Models depend on your authentication tier:

Tier	Models	Limits
Free (Google Login)	Gemini 3 Flash + Pro mix	60 req/min, 1,000 req/day
API Key (Free)	Gemini 3 Flash + Pro	1,000 req/day
Paid / Code Assist	All Gemini models including Pro	Higher limits per plan
Vertex AI	All Gemini models	Usage-based billing