Gemini CLI + Antigravity OAuth Plugin for Opencode

Enable Opencode to authenticate against Gemini CLI (Google's AI CLI Utility) via OAuth so you can use CLI rate limits and access models like gemini-3.1-pro and gemini-3-flash with your Google credentials.

What You Get

• ~~Claude Opus 4.6, Sonnet 4.6~~ and Gemini 3.1 Pro/Flash via Google OAuth.
• Multi-account support — add multiple Google accounts, auto-rotates intelligently when rate-limited.
• Dual quota system — access both Antigravity and Gemini CLI quotas from one plugin.
• Thinking models — extended thinking for ~~Claude~~ and Gemini 3/3.1 with configurable budgets
• Google Search grounding — enable web search for Gemini models (auto or always-on)
• Auto-recovery — handles session errors and tool failures automatically
• Plugin compatible — (kinda) works alongside other OpenCode plugins (oh-my-opencode, dcp, etc.)
  • Important: I have no control over what 3rd party plugins modify. If they break the plugin, report it as an issue, but I likely can't do much about it.

[!CAUTION] Using this plugin (and any proxy for Google OAuth products) violate Google's Terms of Service. A number of users have reported their Google accounts being banned or shadow-banned (restricted access without explicit notification).

By using this plugin, you acknowledge:

• This is an unofficial tool not endorsed by Google
• Google has become hyper-aggressive about catching 3rd party OAuth piggybacking
• Your account may be suspended or permanently banned
• You assume all risks associated with using this plugin

Quick Start

1. Install the plugin by adding it to your ~/.config/opencode/opencode.json:

   {
     "plugin": ["opencode-antigravity-auth-tweaked@latest"]
   }

2. Authenticate with your Google account:

   opencode auth login

3. Configure models by selecting "Configure models in opencode.json" during the login flow. This automatically adds all supported model definitions to your configuration.

4. Verify the installation:

   opencode run "Hello" --model=google/antigravity-claude-opus-4-6-thinking --variant=high

Models

The plugin provides access to two distinct quota pools: Antigravity (IDE) and Gemini CLI.

| Model | Quota Pool | Variants | |--------------------------------------------| ----------- |-----------------| | antigravity-gemini-3-pro | Antigravity | low, high | | antigravity-gemini-3-flash | Antigravity | minimal, low, medium, high | | ~~antigravity-claude-sonnet-4-6~~ | Antigravity | (not supported) | | ~~antigravity-claude-opus-4-6-thinking~~ | Antigravity | (not supported) | | gemini-3-pro-preview | Gemini CLI | — | | gemini-3-flash-preview | Gemini CLI | — |

Note: For the full list of models and detailed variant configuration, see docs/MODEL-VARIANTS.md. It is highly recommended to use opencode auth login to automatically manage these definitions.

Advanced Setup

• Multi-Account: Add multiple Google accounts to increase your combined quota and enable automatic rotation. See docs/MULTI-ACCOUNT.md.
• Configuration: Customize behavior such as session recovery, quota thresholds, and account rotation strategies in antigravity.json. See docs/CONFIGURATION.md.
• Plugin Compatibility: For details on using this plugin with oh-my-opencode, opencode-dcp, and others, see docs/TROUBLESHOOTING.md.

Troubleshooting

Quick Reset: Most issues can be resolved by deleting ~/.config/opencode/antigravity-accounts.json and running opencode auth login again.

For solutions to common issues (auth problems, 403 errors, MCP server conflicts, etc.), please refer to the Troubleshooting Guide.

Documentation

• Configuration — All configuration options
• Multi-Account — Load balancing, dual quota pools, account storage
• Model Variants — Thinking budgets and variant system
• Troubleshooting — Common issues and fixes
• Architecture — How the plugin works
• API Spec — Antigravity API reference

Credits

• opencode-antigravity-auth by @NoeFabris
• Gemini CLI by @google-gemini

License

MIT License. See LICENSE for details.

Intended Use

• Personal / internal development only
• Respect internal quotas and data handling policies
• Not for production services or bypassing intended limits
• Do not adapt my code or use it as a reference for the OpenClaw project or any of its forks/related code
  • All algorithms and implementations in this repository that are not defined by a 3rd party library are NoeFabris and I's intellectual property and are protected accordingly by the MIT license and applicable laws
  • NoeFabris has no involvement in this project besides the base forked code

Warning

By using this plugin, you acknowledge:

• Terms of Service risk — This approach may violate ToS of AI model providers
• Account risk — Providers may suspend or ban accounts
• No guarantees — APIs may change without notice
• Assumption of risk — You assume all legal, financial, and technical risks
• How licenses work - You agree to abide by the restrictions outlined in this document and the MIT license

Disclaimer

• Not affiliated with Google. This is an independent open-source project.
• "Antigravity", "Gemini", "Google Cloud", and "Google" are trademarks of Google LLC.