Is using the official agy CLI through a local MCP server with third-party AI agents permitted?

Google Antigravity
1

Hello Antigravity team,

I’d like to clarify whether using the official Antigravity CLI (agy -p) through a local MCP server with third-party AI agents is permitted under the Terms of Service.

I noticed that previous discussions (e.g., topic #175905 regarding local IPC/PTY wrapping and #184590 regarding the internal Agent API) address related architectures, but there is still ambiguity regarding whether invoking agy -p directly via an MCP server for third-party AI agents is compliant.

Proposed architecture

Third-party AI agent (e.g., Codex CLI or Claude Code) → Local MCP server → Official agy -p → Antigravity

The MCP server would simply:

  • Run locally on my own computer for personal use.
  • Spawn the official, unmodified agy binary as a child process.
  • Pass prompts through the documented headless mode (agy -p).
  • Read the JSON output and return the results to the calling AI agent.
  • Let the official CLI handle authentication using my own Google AI Pro account.

It would NOT:

  • Extract, intercept, store, or forward OAuth tokens.
  • Access private APIs or undocumented internal ports.
  • Use agentapi or directly control the Antigravity desktop application.
  • Share access with other users or bypass usage limits.

My question

The official agy -p command supports headless execution and structured JSON output, which suggests that programmatic integration is an intended use case.

However, Section 6 of the Antigravity Terms of Service restricts access through third-party software and tools.

I would like to clarify the following:

  1. Is wrapping the official agy -p command in a local MCP server permitted when the MCP client is a third-party AI agent such as Codex CLI or Claude Code?

  2. Does invoking agy -p from a third-party AI agent through MCP differ, in terms of policy, from invoking the same command through a regular Python or shell script?

  3. Can this integration use the Antigravity quota included in a personal Google AI Pro subscription, or is separate API billing required?

I am specifically asking about invoking the documented official CLI as a local subprocess, without extracting credentials or accessing private APIs.

I would appreciate explicit clarification from a Google or Antigravity team member regarding this specific architecture.

Thank you!

2

Hi @snowstone,

Thank you for reaching out for policy clarification regarding wrapping the official Antigravity CLI (`agy -p`) in a local MCP server for third-party AI agents (e.g., Claude Code, Codex CLI).

Here are the direct answers to your three policy and architectural questions:

  • Third-Party Agent MCP Wrapper: Wrapping agy -p in a local MCP server to use with third-party agents (like Claude Code or Codex CLI) is not permitted. Per Section 6 of the Terms of Service and our official FAQ, using third-party agent software with your Antigravity login violates our terms and may lead to account suspension.
  • Local Scripts vs. MCP Bridges: Running agy -p in a local script for your own workflow automation is standard CLI usage, whereas building an MCP proxy bridge for third-party agents acts as an unauthorized client layer.
  • Google AI Pro Quota vs. API Billing: Your Google AI Pro subscription quota is strictly for direct use within official Antigravity tools (Antigravity IDE and agy CLI) and cannot be used to power third-party agents.

Recommended Solution for Third-Party Tool Integration:

  • If you wish to use third-party AI agents or custom MCP servers with Google models, please generate an API key via Google AI Studio (https://aistudio.google.com/) or connect via Vertex AI. This provides official programmatic access with pay-as-you-go API billing designed for third-party tools and custom developer integrations.