@trishchuk/antigravity-mcp-server

Antigravity MCP Server

MCP (Model Context Protocol) server for Google Antigravity CLI (agy) integration. Lets any MCP client (Claude Code, Claude Desktop, Cursor, etc.) delegate tasks to Antigravity's agentic CLI — with model selection (Gemini, Claude, GPT-OSS), conversation resume, and workspace controls.

A sibling of @trishchuk/kimi-mcp-server, ported to the Antigravity CLI.

Requirements

• Node.js >= 18
• Antigravity CLI installed (agy --version works) and authenticated (run agy once interactively and sign in with your Google account)

Installation

npm install -g @trishchuk/antigravity-mcp-server

Or run from source:

pnpm install && pnpm build

MCP client configuration

{
  "mcpServers": {
    "antigravity": {
      "command": "npx",
      "args": ["-y", "@trishchuk/antigravity-mcp-server"],
      "env": {
        "AGY_MCP_CWD": "/path/to/your/project"
      }
    }
  }
}

For Claude Code:

claude mcp add antigravity -- npx -y @trishchuk/antigravity-mcp-server

Tools

Tool	Description
ask-antigravity	Run a prompt through agy in print mode. Supports model override, session resume, --add-dir, --sandbox, --dangerously-skip-permissions, dry-run.
plan-antigravity	Generate a structured implementation plan (JSON or markdown) without mutating anything.
review-changes	Collect a git diff (working tree / vs base branch / specific commit) and run a structured code review.
brainstorm	Structured ideation (divergent, convergent, SCAMPER, design-thinking, lateral).
digest-antigravity	Ingest many files/directories and answer a focused question using Antigravity's large model context.
batch-antigravity	Run multiple atomic tasks sequentially or in parallel (priority order, stop-on-error, concurrency cap).
bg-antigravity	Detached background tasks: start / status / tail / stop / remove / list. State persists in ~/.agy-mcp/bg/ across server restarts.
delegate-antigravity	Delegate an implementation task into an isolated git worktree; poll status, then collect the diff for selective review.
list-sessions	List / delete / clear conversation sessions.
list-models	List model labels currently available (agy models).
health	Diagnose CLI installation, authentication, models, and session state.
ping, Help, version, metrics	Utilities.

Background and batch tools default to --dangerously-skip-permissions because print mode cannot answer interactive permission prompts; pass skipPermissions: false to opt out.

Models

The model parameter takes either column of agy models — the model ID (gemini-3.7-flash-high) or the display label (Gemini 3.7 Flash (High)). As of Antigravity CLI v1.1.14:

Model	IDs
Gemini 3.7 Flash (Low | Medium | High)	gemini-3.7-flash-{low,medium,high}
Gemini 3.6 Flash (Low | Medium | High)	gemini-3.6-flash-{low,medium,high}
Gemini 3.5 Flash (Low | Medium | High)	gemini-3.5-flash-{low,medium,high}
Gemini 3.1 Pro (Low | High)	gemini-3.1-pro-{low,high}
Claude Sonnet 4.6 (Thinking)	claude-sonnet-4-6
Claude Opus 4.6 (Thinking)	claude-opus-4-6-thinking
GPT-OSS 120B (Medium)	gpt-oss-120b-medium

Labels and tiers change between CLI releases — use the list-models tool for the live list.

Omit model and the server passes no --model flag, so the CLI's own default applies ("model" in ~/.gemini/antigravity-cli/settings.json). The label this server uses in its examples and hints is Gemini 3.7 Flash (High) — see DEFAULT_MODEL in src/constants.ts.

Sessions and conversation resume

ask-antigravity supports multi-turn conversations:

{
  "prompt": "Analyze src/auth.ts for security issues",
  "sessionId": "auth-review"
}

{
  "prompt": "Now suggest fixes for the issues you found",
  "sessionId": "auth-review"
}

How it works: agy doesn't print its conversation ID to stdout in print mode, so the server passes --log-file to a temp file and parses Print mode: conversation=<uuid> from it. The next call with the same sessionId resumes via agy --conversation <uuid>.

You can also pass a native conversationId directly, or continueLatest: true for agy --continue.

Session storage is in-memory (lost on server restart). Configure with:

• AGY_SESSION_TTL_MS — session TTL (default 24h)
• AGY_MAX_SESSIONS — max stored sessions (default 50)
• AGY_MCP_CWD — default working directory for agy runs

Known quirk

When resuming a conversation, agy print mode replays the previous assistant message before the new response. The server strips the replayed prefix automatically when it can (previous response under 1000 chars); for longer responses a leading echo may remain.

Safety

• skipPermissions: true maps to --dangerously-skip-permissions — agy auto-approves all tool/command permission requests. Use deliberately.
• sandbox: true maps to --sandbox — terminal restrictions enabled.
• By default agy uses your configured permission rules (/permissions in interactive agy).

Development

pnpm build          # tsc
pnpm lint           # tsc --noEmit
pnpm format         # prettier

License

MIT