Drive Google's Antigravity CLI (
agy, powered by Gemini 3.5) without leaving Claude Code.
A Claude Code plugin that hands work to agy — Google's Antigravity CLI — and brings the result back into your session. You stay in Claude Code; Gemini 3.5 becomes a second model on tap. Think of it as the Antigravity counterpart to openai/codex-plugin-cc.
Seven slash commands, all under the /antigravity: namespace. Each one shells out to a small Node companion that wraps agy in headless (-p) mode and manages background jobs.
/antigravity:setup— check thatagyis installed, find its binary and version, and get a best-effort read on whether you're signed in. Never logs you in./antigravity:delegate— hand a task to Gemini 3.5. Write-capable by default; can be sandboxed or made read-only, and can run in the background./antigravity:review— read-only cross-model review of your current diff (orbase...HEAD). Sandboxed./antigravity:resume— continue the most recent Antigravity conversation (or a specific one) with a follow-up./antigravity:status— list background jobs for this repo, or inspect one./antigravity:result— print the final output of a finished job, plus the conversation id and a resume hint./antigravity:cancel— stop a running background job.
You already trust Claude Code for the loop you're in. Sometimes you want a different model in the room — a second opinion on a thorny diff, a second pair of hands on a parallel task, or simply a separate quota when you'd rather not spend yours.
This plugin makes that one slash command away:
- Second opinion.
/antigravity:reviewsends your diff to Gemini 3.5 and reads its critique back. Different model, different blind spots — useful precisely because it isn't the model that wrote the code. - Second pair of hands.
/antigravity:delegateoffloads a self-contained task (a refactor, a script, a migration) toagywhile you keep working. Run it in the background and collect the result later. - Separate quota.
agyruns on your own local Antigravity auth and its own free-preview quota. Offloading to it doesn't draw down your Claude Code usage.
No new account, no API keys, no context switch. If you have agy installed and signed in, you have a second model.
agy— the Antigravity CLI, installed and signed in (Google account, browser OAuth, free preview tier). See install one-liners below.- Node.js >= 18 — the companion is a small ESM script with zero runtime dependencies.
Install agy:
# macOS / Linux → installs to ~/.local/bin/agy
curl -fsSL https://antigravity.google/cli/install.sh | bash# Windows
irm https://antigravity.google/cli/install.ps1 | iexThen sign in once, interactively (this opens a browser):
agyIn Claude Code you can do this without leaving the session — type ! agy, complete the OAuth flow, then quit the TUI.
/plugin marketplace add Idun-Group/antigravity-plugin-cc
/plugin install antigravity@idun-antigravity
/antigravity:setup
/antigravity:setup confirms agy is reachable and tells you what to fix if it isn't.
Cross-model review of your working tree. Read-only and sandboxed — agy reads the diff, it doesn't touch your files.
/antigravity:review
/antigravity:review focus on error handling and edge cases
/antigravity:review --base main the auth refactor in this branch
Returns Gemini 3.5's review of the embedded diff. Pair it with your own review for two models on one change.
Hand a task to Gemini 3.5. Write-capable by default — it can edit files and run commands — so contain it when you want to.
/antigravity:delegate add a --json flag to the export command and update the tests
/antigravity:delegate --read-only explain how the retry logic in client.ts works
/antigravity:delegate --sandbox draft a migration script for the new schema
Background flow — kick it off, keep working, collect later:
/antigravity:delegate --background port the utils module from CommonJS to ESM
→ returns a job id, e.g. agy-l3k9zf-a8x2qd
/antigravity:status
→ agy-l3k9zf-a8x2qd running "port the utils module…"
/antigravity:status agy-l3k9zf-a8x2qd
→ agy-l3k9zf-a8x2qd done
/antigravity:result agy-l3k9zf-a8x2qd
→ final output + conversation id + a /antigravity:resume hint
Job ids look like
agy-<id>; conversation ids are UUIDs (e.g.f47ac10b-58cc-4372-a567-0e02b2c3d479).status/result/cancelaccept a job id, and default to the latest job when you omit it.
Continue the last Antigravity conversation (or a specific one) with a follow-up.
/antigravity:resume now add unit tests for the code you just wrote
/antigravity:resume --conversation f47ac10b-58cc-4372-a567-0e02b2c3d479 also handle the empty-input case
/antigravity:status # all jobs for this repo
/antigravity:result # latest finished job's output
/antigravity:cancel agy-l3k9zf-a8x2qd # stop a running job
The plugin is a thin layer over agy's headless mode. Honestly, most of the value is in the plumbing:
- Headless delegation. Commands run
agy -p "<task>"and stream the result back.delegateis write-capable;reviewis sandboxed and read-only. - Background jobs.
--backgroundspawns a detached run, tracks it per-repo, and lets you poll withstatus/ collect withresult/ stop withcancel. - Error surfacing — the differentiator. On quota exhaustion,
agyexits0with empty stdout — success-looking, but nothing happened. The companion scansagy's--log-fileto catch that case and surface the real signal:RESOURCE_EXHAUSTED (429) … Resets in <duration>, auth failures, and backend errors that the exit code hides. It also recovers the conversation id from the log soresumeandresultactually work.
On model selection: there is no --model flag on agy. The model (default Gemini 3.5 Flash) is chosen with /model inside agy and persisted in its settings.json. Run ! agy, type /model, pick one — that choice sticks for headless runs too.
"RESOURCE_EXHAUSTED" / quota exhausted.
You've hit the free-preview limit. The quota is per Google account (agy reports "Individual quota reached"), and the companion tells you when it resets (e.g. "Resets in 152h"). Options: wait for the reset, or sign agy into a different Google account (! agy, then sign in). Claude Code can keep handling the task itself in the meantime. This is a preview-tier limit, not a bug.
Empty output but no error.
Almost always quota — agy exits 0 with empty stdout when exhausted. Re-run the command; the companion reads the log and should now report the RESOURCE_EXHAUSTED reset time.
"Not authenticated" / setup says you're not signed in.
Run agy once interactively to complete the Google browser OAuth: in Claude Code, type ! agy, sign in, then quit. The plugin never authenticates for you.
agy is in a custom path.
The companion looks on PATH, then ~/.local/bin/agy. To point it elsewhere, set ANTIGRAVITY_CC_AGY_BIN to the full path of your binary.
Do I need a separate account or an API key?
No. There's no API key for the preview tier. The plugin uses whatever local agy auth you already have — sign in once with your Google account and you're set.
A background job is stuck.
/antigravity:status agy-<id> to inspect it, /antigravity:cancel agy-<id> to stop it.
agy has its own plugin system and can even import Claude-compatible plugins (agy plugin import claude). That's the other direction — extending Antigravity with Claude-shaped tooling.
This project lives on the Claude Code side: it lets Claude Code drive agy. The two are complementary; neither requires the other.
Built and maintained by Idun Labs — makers of an open-source platform for governing AI agents in production.
- Antigravity CLI docs → https://antigravity.google/docs/cli-overview
- Inspiration →
openai/codex-plugin-cc
Licensed under MIT. PRs welcome.
Independent project. Not affiliated with, endorsed by, or sponsored by Google or Anthropic. "Antigravity", "Gemini", and "Claude Code" belong to their respective owners.