Forkbench for Antigravity CLI
The Mac terminal built for Antigravity CLI
Antigravity CLI is Google's terminal agent, a Go binary you invoke as agy. It replaced the standalone Gemini CLI in June 2026 and is built around composing several specialised agents that work in parallel and hand work between them.
Updated
Forkbench is a Mac app for running Antigravity CLI where the API key it needs is used by the command and never enters the agent's prompt, command line or transcript, and a Thread can be locked to the folders that job is about, enforced by the macOS kernel. agy gets a real login shell in its own tab, its MCP servers are registered for you, and it shares one task board and one set of notes with whatever other agents you run - which is Pro once more than one of them works the same board.
What breaks in a plain terminal
Antigravity is designed around several agents running at once, which makes the coordination problems arrive on day one rather than gradually. Two agents editing the same working tree collide. Nothing outside a conversation records what was decided, so a closed pane takes the reasoning with it. And parallel agents still share one environment, so a credential exposed to one is exposed to all of them at once.
How Forkbench runs Antigravity CLI
A worktree per agent
Give each agent its own git worktree from the same repo so several can work at once without touching each other's files. Nothing collides because nothing is shared but the history.
MCP set up for you
Forkbench registers its notes, board and Vault servers into Antigravity's own MCP configuration, alongside Claude Code, Codex and Cursor. It is one of the four agents that needs no hand-editing.
A board that outlives the pane
The plan, the tasks, the blockers and the discussion that settled a question sit outside any one conversation, so closing a pane or rebooting loses none of it. Nothing an agent reports finished counts as done until you accept it.
Notes any of them can read and write
What one agent works out goes into the Thread as a note, and the next agent reads it on arrival - including an agent from a different vendor entirely. Sealed on your Mac before it is stored.
Keys they can use and never read
A key in Vault reaches the one command that needs it. The agent gets the result and never the value, which matters more, not less, when several agents share one environment. Vault is part of Pro.
Folders they cannot wander out of
Lock a Thread to the folders the job is about. Every shell in it starts under a macOS Seatbelt profile the kernel enforces and every process inherits, including build scripts and a dependency's install hook, so a read or a delete outside them is refused rather than discouraged.
Getting Antigravity CLI running
- 1Open a Thread on your repo and run agy in a tab.
- 2Give each additional agent its own worktree from the same Thread, so parallel work cannot collide.
- 3Grant the Thread the notes it should read. Everything is deny by default until you grant it.
- 4Put the job's keys in Vault and let the commands that need them run, rather than exporting anything into the environment the agents share.
- 5Come back to the board and accept what the agents report finished.
What this does not do: Antigravity CLI is a young product and Google changes it often; behaviour described here was checked on 6 September 2026, and its own documentation is the authority. Forkbench registers its MCP servers and gives it a real login shell - it does not wrap, proxy or model-route the agent, and it cannot see your remaining quota.
Antigravity CLI questions
Is Antigravity CLI the same as Gemini CLI?
It is the replacement, not a rename. Google retired the standalone Gemini CLI on 18 June 2026 for AI Pro, Ultra and free tiers and pointed those users at Antigravity CLI, which is a different binary, invoked as agy, with a different architecture built around parallel agents.
Does Antigravity CLI run normally inside Forkbench?
Yes. Each tab is a real login shell, so agy starts exactly as it does in any terminal, with your shell config and aliases unchanged.
Can Antigravity work alongside Claude Code or Codex?
Yes. Put them in one Thread and they claim from the same backlog. No task records which agent wrote it, so any of them can pick up another's work, with the notes and the discussion still attached.
Does my context carry over from Gemini CLI?
The instruction file does, with a copy or a symlink. What does not is anything your old sessions worked out and never wrote down - that lived in one vendor's session history. Filing it as notes on the Thread before you switch is what keeps it, and it is then readable by whichever agent you run next.
What does it cost to run Antigravity CLI in Forkbench?
Nothing extra for the agent. You keep your own Google plan or API key, and Forkbench never meters requests. The terminal, your notebooks and a board on every Thread are free. Vault and running more than one agent on the same board are Pro, and every account starts with 30 days of it without a card.
Running something else?
Forkbench is agent-agnostic, so any CLI agent runs in a tab. These have a page of their own: