What it does

Antigravity Manager is an Electron desktop app for wrangling multiple Google Gemini and Claude accounts. It tracks per-account quota in real time, swaps to the next available account when you hit rate limits, and runs a local API proxy that speaks OpenAI/Anthropic-shaped requests. It also handles backups, process control for the Antigravity IDE, and per-account HTTP/SOCKS5 proxy routing.

The interesting bit

The auto-switching logic is the meat: it monitors accounts every five minutes, falls back when quota drops below 5% or a 429 hits, and can map models on the fly (e.g., pretend Claude is Gemini). That’s the kind of glue that stops you from manually swapping API keys at 2 AM.

Key highlights

• AES-256-GCM encryption for stored credentials, with OS-native keychain integration and auto-migration of old plaintext data
• Built-in local proxy server with configurable port, timeout, and model remapping
• Nix flake included for NixOS/Home Manager installs (marked unfree: CC-BY-NC-SA-4.0)
• Batch import/export of account pools with deduplication and schema validation
• System tray mode, desktop notifications at custom quota thresholds, and IDE state.vscdb sync

Caveats

• macOS users need to manually strip quarantine attributes and re-sign the app after every update, since it is unsigned
• The license is CC-BY-NC-SA-4.0 (non-commercial), which may block corporate use
• Requires Node.js 18+ to build from source; no mention of automated update mechanism

Verdict

Grab it if you are burning through Gemini or Claude free tiers and want automated failover without writing your own proxy. Skip it if you need a single account, a headless server, or a permissive license.