The opencode-antigravity-auth repository is a TypeScript-based authentication plugin that enables the Opencode CLI to authenticate against Antigravity, Google's IDE, via OAuth. This allows users to access advanced AI models including Claude Opus 4.6, Claude Sonnet 4.6, and Gemini 3.1 Pro using their Google credentials while leveraging Antigravity's rate limits and access models. The plugin is designed to work seamlessly with the Opencode ecosystem and supports integration alongside other plugins like oh-my-opencode and dcp.
The repository's primary functionality centers on providing dual quota system access, allowing users to tap into both Antigravity and Gemini CLI quotas from a single plugin interface. The plugin supports extended thinking models for both Claude and Gemini with configurable thinking budgets, and includes Google Search grounding capabilities that enable web search functionality for Gemini models with both automatic and always-on options. Multi-account support is a key feature, enabling users to add multiple Google accounts with automatic rotation when rate limits are encountered, effectively increasing combined quota availability.
According to GitGenius activity tracking, the repository shows strong engagement with 289 tracked issues and pull requests. The median response latency for issues and PRs is 0.0 hours with a mean of 11.6 hours, indicating active maintenance. The most frequently labeled issues are bugs with 147 occurrences, followed by enhancement requests with 56 items and questions with 41 items. The primary contributor NoeFabris has logged 376 events, with tctinh contributing 322 events and titet11 adding 57 events, demonstrating concentrated but collaborative development.
The repository is classified across multiple technical domains including authentication, user accounts, API services, token-based systems, JWT, Node.js, TypeScript, security, backend services, and credential management. The codebase includes comprehensive documentation covering model variants, multi-account setup, and troubleshooting procedures. The plugin handles automatic session recovery from errors and tool failures, and provides sophisticated model routing behavior where Antigravity-first routing is the default but can be switched to CLI-first mode for alternative quota pool prioritization.
The README includes explicit warnings about Terms of Service violations, noting that using this unofficial tool violates Google's Terms of Service and that users have reported account bans and shadow-bans. The installation process offers both manual setup and LLM agent-assisted configuration options. The plugin supports a comprehensive set of models including antigravity-gemini-3-pro, antigravity-gemini-3.1-pro, antigravity-gemini-3-flash, antigravity-claude-sonnet-4-6, and antigravity-claude-opus-4-6-thinking, each with configurable variants for different thinking levels.
The repository maintains detailed troubleshooting documentation addressing common issues including multi-account authentication problems, permission errors, model compatibility issues with MCP servers, rate limiting cascades, OAuth callback failures on Safari, and port conflicts. Configuration files are stored in platform-agnostic locations under ~/.config/opencode/, with support for custom paths via environment variables. The plugin includes automatic model name transformation for both Antigravity and Gemini CLI APIs, maintaining backward compatibility with legacy model naming conventions.
