Google Antigravity vs Gemini Code AssistUpdated 2026-03-18

SUMMARY

Google Antigravity (IDE) uses markdown configuration while Gemini Code Assist (IDE) uses markdown. They differ on 0 of 11 compared features. Both tools provide AI-assisted development but take different approaches to project configuration.

FEATURE COMPARISON

FeatureGoogle AntigravityGemini Code Assist
Config formatmarkdownmarkdown
Hierarchy support
Global config
Project config
Subdirectory scoping
File inclusion / imports
Ignore file
IDE integration
Schema / structureFree-form (Markdown)Free-form (Markdown)
Git committed
EncodingUTF-8UTF-8

FILE MAPPING

PurposeGoogle AntigravityGemini Code Assist
Project instructionsAGENTS.mdGEMINI.md
Project instructionsGEMINI.mdAGENT.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 Code Assist
GEMINI.md
markdown
# Project Rules

## Overview
E-commerce platform built with Go microservices and React frontend.
All services communicate via gRPC with Protocol Buffers.

## Go Services
- Follow standard Go project layout (cmd/, internal/, pkg/)
- Use structured logging with slog (not log or fmt.Println)
- Error handling: always wrap errors with fmt.Errorf("%w", err)
- Database access through repository pattern in internal/repo/
- All public functions must have godoc comments

## API Design
- Proto files live in proto/ directory with buf for linting
- Use field masks for partial updates
- Pagination via cursor-based tokens, not offset

## Testing
- Table-driven tests for all business logic
- Use testcontainers-go for integration tests
- Minimum 80% coverage on internal/ packages
- Mock external services with gomock interfaces

## Do Not
- Use global variables or init() functions
- Import internal packages across service boundaries
- Commit generated .pb.go files (CI generates them)

WHICH SHOULD I USE?

Recommendation

Choose based on your IDE/CLI preference. If you use Google Antigravity, configure AGENTS.md. If you use Gemini Code Assist, 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

SEE ALSO

agentconfig.ing2026-03-18COMPARE(1)