Google Antigravity vs Gemini CLI

Google Antigravity vs Gemini CLIComparisonUpdated 2026-03-18

SUMMARY

Google Antigravity (IDE) uses markdown configuration while Gemini CLI (CLI) uses markdown. They differ on 3 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

Feature	Google Antigravity	Gemini CLI	Notes
Config format	markdown	markdown
Hierarchy support	✓	✓	Whether config files can be placed at multiple directory levels
Global config	✗	✓	User-wide configuration outside any project
Project config	✓	✓
Subdirectory scoping	✓	✗	Config files in subdirectories that apply only to that subtree
File inclusion / imports	✗	✗	Ability to include or reference other files from config
Ignore file	✗	✗
IDE integration	✓	CLI
Schema / structure	Free-form (Markdown)	Free-form (Markdown)	Whether config uses structured schema or free-form content
Git committed	✓	✓	Whether primary config files are intended to be version-controlled
Encoding	UTF-8	UTF-8

FILE MAPPING

Purpose	Google Antigravity	Gemini CLI
Project instructions	AGENTS.md	GEMINI.md
Project instructions	GEMINI.md	.gemini/styleguide.md

SIDE-BY-SIDE CODE SAMPLES

Google Antigravity

AGENTS.md

markdown

# Project Instructions

## Architecture
- Monorepo with apps/ and packages/ directories
- Each app is a standalone Next.js deployment
- Shared packages use TypeScript project references

## Code Standards
- TypeScript strict mode everywhere
- Use Zod for runtime validation at API boundaries
- Prefer server components; use "use client" only when needed
- All database queries go through the data-access layer

## Testing
- Unit tests with Vitest for business logic
- Integration tests for API routes
- E2E tests with Playwright for critical user flows

## Deployment
- Preview deployments on every PR
- Production deploys from main branch only
- Environment variables managed via .env.local (never committed)

Gemini CLI

GEMINI.md

markdown

# Project Context

## Stack
- Node.js 22 with TypeScript 5.x
- Express.js for the API server
- Prisma ORM with PostgreSQL
- React 19 with Vite for the frontend

## Architecture
- Monorepo with pnpm workspaces
- packages/api — Express REST API
- packages/web — React SPA
- packages/shared — Shared types and utilities

## Commands
- pnpm dev — Start all services
- pnpm test — Run vitest across all packages
- pnpm lint — ESLint + Prettier check
- pnpm db:migrate — Run Prisma migrations

## Conventions
- Use barrel exports (index.ts) for public APIs
- Error responses use RFC 7807 Problem Details format
- All API endpoints require authentication except /health

KEY DIFFERENCES

1. Global config

Google Antigravity: Not supported. Gemini CLI: Supported.

2. Subdirectory scoping

Google Antigravity: Supported. Gemini CLI: Not supported.

3. IDE integration

Google Antigravity: Supported. Gemini CLI: CLI.

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use Google Antigravity, configure AGENTS.md. If you use Gemini CLI, configure GEMINI.md. Many projects include config files for multiple tools so each team member can use their preferred editor.

PORTABILITY TIP

sync-instructions.sh

bash

# Maintain a single source of truth:
cp AI-INSTRUCTIONS.md CLAUDE.md
cp AI-INSTRUCTIONS.md .cursorrules
cp AI-INSTRUCTIONS.md AGENTS.md