Antigravity
Google's Antigravity CLI (agy) in Open Free Max — model choice beyond Gemini, conversation resume by id, and MCP wiring through a project-scoped plugin instead of your global config.
Antigravity ships as the agy binary. It is the second CLI, after Claude Code, that can see
Open Free Max’s own project memory — and the one with the most awkward configuration surface,
which is worth understanding before you rely on it.
What OFM does with it
- Resume by conversation id.
agy --conversation <id>when OFM knows the id, otherwiseagy --continue. The id is read from Antigravity’s own cache, which is indexed by working directory, so a resume never picks up another project’s conversation. - Project memory as MCP tools. When memory wiring is on, OFM merges its stdio memory servers into a project plugin so Antigravity sessions can query the history and knowledge base.
- History ingestion. Antigravity transcripts feed project memory, including which model was actually used — it is read from the transcript, because a single Antigravity session can switch between a Gemini model and a Claude model, and the two do not cost the same.
Launch flags
| Setting | Effect |
|---|---|
| Model | e.g. gemini-3.6-flash-high, claude-sonnet-4-6. Antigravity also serves non-Google models |
| Reasoning effort | Thinking budget — higher is slower and heavier on your subscription quota |
| Execution mode | plan (read-only) or accept-edits (auto-approves edits) |
| Skip every permission | Auto-approves every tool request; Mission Control can no longer hold anything back |
| Sandbox | Runs the session with terminal restrictions enabled |
| Agent | Named agent to use — agy agents lists them |
| Added folders | Extra directories added to the workspace |
| Project / New project | Antigravity project id, or create a fresh one for this session |
| Log file | Overrides where the CLI writes its log — diagnosis only |
The configuration constraint
agy --help exposes no MCP configuration flag at all — neither Claude’s --mcp-config nor
Codex’s -c mcp_servers.…. The only channel is a file on disk, and there are two candidates:
~/.gemini/config/mcp_config.json— global, and shared with the Antigravity desktop app and IDE. Writing it would silently reconfigure two other products.<project>/.agents/plugins/ofm/— project-scoped, visible in your repository, and removable by deleting a folder.
OFM writes the second. You will see .agents/plugins/ofm/plugin.json and mcp_config.json
appear in a project that has memory or a vault wired; adding .agents/ to .gitignore is a
reasonable move if you do not want them versioned.
Two deliberate details in that file: the bearer token lives in the descriptor’s env table and
never in args (a command line is visible to every process on the machine), and OFM never
writes a hooks.json — a PreToolUse hook answering allow would short-circuit Mission
Control’s hard deny-list.
Known reservation
Plugin-provided MCP servers could not be observed loading during OFM’s compatibility work: an intentionally invalid descriptor stayed silent, while the same error is logged for the global file. The servers may only be mounted when a conversation opens. The honest consequence: an Obsidian vault may remain inactive for Antigravity until this is reconfirmed in a live session. The documented fallback is the global file, which requires an explicit opt-in because it reaches outside OFM’s scope.
Installation
Install agy with the assistant in the agent tab, then re-check. Under
WSL, install inside the distribution.
Frequently asked
- Is Antigravity the same as the old Gemini CLI?
- No. Antigravity is a different CLI with a different binary (agy) and a different conversation store, and it can serve non-Google models. Open Free Max drives Antigravity; the legacy gemini binary is no longer a supported provider.
- Where does OFM write the Antigravity MCP configuration?
- Into .agents/plugins/ofm/ inside your project, never into ~/.gemini/config/, which is shared with the Antigravity desktop app and IDE.