ACP adapter for Google Antigravity CLI

Usage

agy-acp automatically uses an installed agy binary if it exists and no binary is explicitly specified. If no existing binary is detected or specified, it installs the latest version during initialize from the official google-antigravity/antigravity-cli GitHub repository into ~/.local/bin/agy (checksum-verified when a digest is published).

Or install agy yourself using the official installer script or Homebrew:

# Official script
curl -fsSL https://antigravity.google/cli/install.sh | bash

# Homebrew
brew install antigravity-cli

Zed Configuration

Add agy-acp as a custom agent in Zed:

{
  "agent_servers": {
    "Google Antigravity": {
      "command": "npx",
      "args": ["agy-acp"]
    }
  }
}

Environment

| Variable | Default / notes | |---|---| | PATH | Must include agy if the editor doesn't inherit your shell PATH | | AGY_BIN | Override the agy binary path |

Architecture

Zed / ACP client
  -> agy-acp (v1 or draft v2 from initialize)
  -> AcpAgent (sessions, config, prompt lifecycle)
  -> AgyCliSession (interactive agy PTY, --conversation id)
  -> agy --prompt-interactive ... --conversation <id> --sandbox ...
       \-> ~/.gemini/antigravity-cli/conversations/<id>.db
  -> StreamPoller + Translator -> ACP session/update notifications

• One interactive agy PTY per ACP session; conversation id is learned on the first turn and reused. PTY output is a diagnostic tail only — never parsed as agent text.
• Steps come from agy's conversation SQLite DB (structured protobuf records), not stdout.
• Config options: mode → --mode, model → --model, reasoningEffort → --effort
• Cancel: SIGINT then SIGKILL. --sandbox on by default; skip-permissions is opt-in.
• Session bindings persist under ~/.agy-acp-state so list/load/resume survive restarts.
• v1: session/load replays history; session/resume reattaches without replay. v2: only session/resume — pass replayFrom: { "type": "start" } to replay.

Wire format decoding was cross-referenced with shubzkothekar/antigravity-acp (MIT); decoding code is our own.

Development

npm run build && npm test
node dist/main.js

# smoke initialize
printf '%s\n' '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":1}}' | node dist/main.js

Disclaimer

Google's FAQ states that third-party tools to access Antigravity violate their Terms of Service and may lead to account suspension.
Prefer Vertex / AI Studio API keys for lower-risk use. Use this only on test/secondary accounts.

Provided as-is, no warranty. By using agy-acp you accept this notice and Google's ToS.

Use at your own risk.