Antigravity#

T3 Code runs Google's official Antigravity ACP agent on your selected environment. T3 manages its own CLI installation and sign-in, separate from your terminal or IDE. Google controls which models and account access are available through this agent.

Set up Antigravity#

On web or desktop, open Settings > Providers, choose the environment that runs your project, and enable Antigravity. Install its runtime there, then choose Sign in and complete the browser sign-in. Wait for T3 Code to confirm account access and load models before starting a thread. Once the runtime is installed, you can also sign in from Settings > Providers in the mobile app.

Installation continues if you leave settings or reconnect. Setup requires permission to operate the environment; update an older server if it does not offer Antigravity setup.

Sign in from a remote device#

Google returns to a 127.0.0.1 address. It can finish directly when your browser is on the environment's machine. From another device, the final page will usually fail to load because the sign-in listener is on the environment.

Copy the full return address, including everything after ?, into the return URL field in the client where you started sign-in, then choose Continue. Keep the original address; do not replace it with the server's hostname. Only that T3 Code sign-in session can finish the attempt. If it expires, retry sign-in and use the new link.

The return URL contains a temporary sign-in code. Paste it only into the setup field. A successful callback page alone does not confirm account access; wait for T3 Code's confirmation.

Other sign-in methods#

Choose Sign-in method in the Antigravity provider settings:

Method	Credentials
Google account	Personal Google sign-in in the browser
Gemini Enterprise	Browser sign-in, GCP project, and GCP location
Gemini API key	API key; choose Connect without a browser
Agent Platform / Vertex AI	API key, or GCP project and location with Application Default Credentials on the environment

The environment stores the Antigravity API key outside its settings file, and clients only see whether one is saved. The agent uses the method and credentials selected for this instance; ambient GEMINI_API_KEY and Google credential variables do not override them. Changing the method stops the instance's sessions. Sign out before replacing an account.

Runtime installation#

Managed installation supports Apple Silicon and Intel macOS, Linux x64 or ARM64 with glibc or musl, and Windows x64 or ARM64. Allow at least 1.25 GiB of free disk space for downloading and staging an update.

Use a manual installation#

Install Antigravity CLI on the environment. Set Binary path to its agy executable and update it yourself. Leave the field blank to use the managed runtime, or a compatible executable on PATH if no managed runtime is installed.

Update the managed runtime#

In web or desktop provider settings, choose Update Antigravity when an update is available. T3 checks Google's CLI release channel while provider update checks are enabled. Installing or reinstalling also checks that channel. Updates keep your profile and existing runtime available if the new release fails validation.

Updating an older 1.4.5 installation migrates it to the native CLI. You may need to sign in again after migration. Threads already running finish with their original runtime; new sessions use the updated release. Custom binary paths keep using the executable you selected.

Models and threads#

The model list comes from your Antigravity account, including Claude and GPT models when your plan has them. Pick a thinking level beside the model list in the model picker; it shows only the levels the selected model supports. A resumed thread keeps its selected model. If access to that model ends, select another available model before continuing.

Antigravity creates empty .gemini/skills and .agents/skills folders in the workspace when a session starts. Git does not track empty folders, so they never appear in commits.

Use Antigravity's native /plan command for planning. Tool approvals follow Permission modes. Questions with fixed choices still need one of the offered answers, even in Full access.

T3 Code keeps conversation history and file diffs, but Antigravity cannot rewind its conversation. Reverting a thread or editing and resubmitting an earlier turn is unavailable. Continue with a follow-up message or start a new thread.

Manual context compaction is unavailable through Antigravity's ACP runtime, even though its CLI has /compact. Send /clear when you need a fresh context.

Skills and attachments#

Put project skills in .agents/skills. T3 Code also reads .gemini/skills and the legacy .agent/skills directory. Among these project locations, the first copy wins in this order: .gemini/skills, .agents/skills, .agent/skills. See commands and skills for invoking them.

Skills for every project go in ~/.gemini/config/skills or ~/.gemini/antigravity-cli/skills. Antigravity does not read ~/.agents/skills, so a skill there only appears when the project itself is your home directory.

Antigravity receives images and audio directly, and reads PDFs and text files as documents. With the managed runtime on macOS and Linux, an MP4 video up to 20 MiB is sent as video to Gemini models. Other attachments, and videos for other models, are passed as a saved file path for the agent to inspect with its tools.

Subagents#

Antigravity groups subagent activity into batches. Open a batch and select Subagent work (Work on mobile) to read each child's role, prompt, and recent steps. This view is read only: you cannot message or control individual subagents, and an idle batch does not confirm that every child succeeded. If Antigravity did not record which children a batch started, the view says so. See agent work for where to inspect activity.

Accounts and removal#

Add an Antigravity provider instance for each Google account in Settings > Providers on web or desktop. Each has its own sign-in; downloaded runtimes are shared on the environment.

Action	Effect
Disable	Stops the instance's sessions and keeps its Google sign-in.
Sign out	Stops the instance's sessions and removes its saved Google login.
Remove downloaded runtime	Removes the shared installation and keeps Google credentials.

All three keep thread history and workspace files. Sending /logout by itself in a thread signs out its instance, including stopping that instance's other sessions. Sign out, then sign in again to replace an account.

Before removing a managed runtime, disable its instances and cancel any active installation. Clear any explicit binary path pointing into that runtime. Removal is refused while the runtime is in use.

Run a native goal#

When your Antigravity runtime offers /goal, send /goal followed by a verifiable objective. Antigravity keeps working until it completes the goal or you cancel it. If you still use the older 1.4.5 runtime, update Antigravity in provider settings, then refresh provider status.

Use Stop to interrupt a running goal, then ask Antigravity to stop pursuing it before starting more work. Ordinary follow-ups wait until the running turn ends. T3 does not support Antigravity goal status, pause, resume, or clear commands.

Check access and troubleshoot#

Open Usage > Limits to see the remaining Gemini and shared Claude/GPT allowances for Google sign-ins. Each group has separate five-hour and weekly limits and reset times. Limits refresh with provider status and include usage outside T3 Code.

A server restart keeps your Google sign-in. The provider shows the saved account until a session, a refresh, or a sign-out reports something new.

To check access and reload models, use Refresh provider status in web or desktop provider settings, or Refresh models in mobile thread settings. If asked to sign in again, use provider settings on web or desktop, or Settings > Providers on mobile.

If Google reports SUBSCRIPTION_REQUIRED, an account restriction, or a usage limit, follow the provider's message and any retry time. See Google's account plans for eligibility.