docker/sbx-kit-antigravity repository overview

⁠Google Antigravity

A standalone Docker Sandboxes workload kit (kind: workload, schemaVersion: "3") for Google Antigravity⁠. It runs the agy terminal coding agent with sandbox-local permissions pre-approved and supports either Antigravity's Google OAuth login or a Gemini API key.

There is also an antigravity-mixin⁠ variant of the same kit, for layering agy onto a shell workload instead of running a sandbox of its own.

⁠Usage

Use the published kit:

sbx run "docker.io/docker/sbx-kit-antigravity:latest"

Or load it directly from this repository:

sbx run "git+https://github.com/docker/sbx-kits-contrib.git#dir=antigravity"

Or use a local clone:

sbx run ./antigravity/

⁠Authentication

For OAuth, choose skip if sbx offers to configure the optional google credential. Antigravity then starts its native Google sign-in flow. Open the displayed URL in your browser, complete sign-in, and paste the authorization code back into the terminal. The resulting session is retained in the sandbox's persistent home directory.

For API-key mode, provide the key when sbx offers to configure the google credential, or store it before launching:

sbx secret set google
sbx run "docker.io/docker/sbx-kit-antigravity:latest"

The kit exposes GEMINI_API_KEY as a proxy sentinel and injects the real key only into requests to generativelanguage.googleapis.com. It also sets Antigravity's required modelProvider setting to gemini. Removing the stored credential and recreating the sandbox switches back to OAuth mode.

⁠MCP gateway

When Docker Sandboxes provides an MCP gateway, the kit registers it in Antigravity's user-level MCP configuration with the proxy-managed bearer sentinel. Existing MCP servers in that file are preserved.

⁠Content

A kind: workload kit's layers are the sandbox's root filesystem, so the kit has content rather than a reference to an image built elsewhere. That content is built from antigravity.dockerfile⁠, the companion recipe the descriptor finds by filename stem: docker/sandbox-templates:shell-docker as the base, with agy installed by Google's official installation script. The installer resolves the current release and verifies its published checksum — which is also why the descriptor declares no version arg and publishes an unversioned provides: ["antigravity"] under its version: fallback: there is no pin for one to reference. install.sh accepts only -d|--dir and -h|--help and reads no version variable, the manifest's download URL carries an opaque build id beside the version so it is not constructible from one, and agy self-updates in the background at runtime — which the kit's runtime allow list deliberately permits. An unversioned provide matches only unconstrained requires, which is the honest claim here; antigravity.yaml⁠ records the full argument and what upstream would have to change.

Because the install happens at build time, the kit's network policy declares no install phase — a build runs before any phase the policy scopes, and the kit's two lifecycle hooks are startup hooks that reach nothing off-box.