Package Exports

opencode-antigravity-auth
opencode-antigravity-auth/dist/index.js
opencode-antigravity-auth/dist/src/constants
opencode-antigravity-auth/dist/src/constants.js
opencode-antigravity-auth/dist/src/plugin/request.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (opencode-antigravity-auth) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

opencode-antigravity-auth

OpenCode plugin for Google Antigravity OAuth authentication.

Features

Dual Quota System - Access both Antigravity quota (Claude, Gemini 3) and Gemini CLI quota from a single plugin
Multi-Account Rotation - Add multiple Google accounts; automatically rotates when one is rate-limited
Plugin Compatible - Works alongside other OpenCode plugins (opencodesync, etc.)
Extended Thinking - Native support for Claude thinking budgets and Gemini 3 thinking levels
Auto Recovery - Automatic session recovery from Claude tool_result_missing errors

Installation

npm install opencode-antigravity-auth

Add to your OpenCode config (~/.config/opencode/opencode.json):

{
  "plugins": ["opencode-antigravity-auth@latest"],
  "provider": "google",
  "model": "google/antigravity-gemini-3-flash"
}

On first run, a browser window opens for Google OAuth. Tokens are stored securely and refresh automatically.

Installation Guide for LLM Agents

Step-by-Step Instructions

Edit the OpenCode configuration file:
- Linux/Mac: ~/.config/opencode/opencode.json
- Windows: %APPDATA%\opencode\opencode.json
Add the plugin to the plugins array
Set provider to "google" and choose a model

Complete Configuration Example

Create ~/.config/opencode/antigravity.json

{
  // JSON Schema for IDE autocompletion
  "$schema": "https://raw.githubusercontent.com/anthropics/opencode-antigravity-auth/main/assets/antigravity.schema.json",

  // === General ===
  "quiet_mode": false,           // Suppress toast notifications (except recovery)
  "debug": false,                // Enable debug logging to file
  "log_dir": "/custom/log/path", // Custom debug log directory (optional)
  "auto_update": true,           // Auto-update plugin

  // === Thinking Blocks ===
  "keep_thinking": false,        // Preserve thinking blocks (may cause signature errors)

  // === Session Recovery ===
  "session_recovery": true,      // Auto-recover from tool_result_missing errors
  "auto_resume": true,           // Auto-send "continue" after recovery
  "resume_text": "continue",     // Custom resume prompt text

  // === Empty Response Handling ===
  "empty_response_max_attempts": 4,      // Max retries for empty responses
  "empty_response_retry_delay_ms": 2000, // Delay between retries (ms)

  // === Tool Handling ===
  "tool_id_recovery": true,       // Fix mismatched tool IDs from context compaction
  "claude_tool_hardening": true,  // Prevent Claude tool hallucinations

  // === Token Refresh ===
  "proactive_token_refresh": true,              // Background token refresh
  "proactive_refresh_buffer_seconds": 1800,     // Refresh 30min before expiry
  "proactive_refresh_check_interval_seconds": 300, // Check every 5min

  // === Rate Limiting ===
  "max_rate_limit_wait_seconds": 300, // Max wait time when rate limited (0=unlimited)
  "quota_fallback": false,            // Try alternate quota when rate limited

  // === Signature Cache (for keep_thinking=true) ===
  "signature_cache": {
    "enabled": true,
    "memory_ttl_seconds": 3600,      // 1 hour in-memory
    "disk_ttl_seconds": 172800,      // 48 hours on disk
    "write_interval_seconds": 60     // Background write interval
  }
}

Create ~/.config/opencode/opencode.json

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": [
    "opencode-antigravity-auth@latest"
  ],
  "provider": {
    "google": {
      "models": {
        "antigravity-gemini-3-pro-low": {
          "name": "Gemini 3 Pro Low (Antigravity)",
          "limit": { "context": 1048576, "output": 65535 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-gemini-3-pro-high": {
          "name": "Gemini 3 Pro High (Antigravity)",
          "limit": { "context": 1048576, "output": 65535 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-gemini-3-flash": {
          "name": "Gemini 3 Flash (Antigravity)",
          "limit": { "context": 1048576, "output": 65536 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5": {
          "name": "Claude Sonnet 4.5 (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-low": {
          "name": "Claude Sonnet 4.5 Think Low (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-medium": {
          "name": "Claude Sonnet 4.5 Think Medium (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-high": {
          "name": "Claude Sonnet 4.5 Think High (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-low": {
          "name": "Claude Opus 4.5 Think Low (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-medium": {
          "name": "Claude Opus 4.5 Think Medium (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-high": {
          "name": "Claude Opus 4.5 Think High (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        }
      }
    }
  }
}

Beta Versions

For the latest development features, check the dev branch README for beta installation instructions.

Available Models

Antigravity Quota

Models with antigravity- prefix use Antigravity quota:

Model	Description
`google/antigravity-gemini-3-flash`	Gemini 3 Flash (minimal thinking)
`google/antigravity-gemini-3-pro-low`	Gemini 3 Pro with low thinking
`google/antigravity-gemini-3-pro-high`	Gemini 3 Pro with high thinking
`google/antigravity-claude-sonnet-4-5`	Claude Sonnet 4.5 (no thinking)
`google/antigravity-claude-sonnet-4-5-thinking-low`	Sonnet with 8K thinking budget
`google/antigravity-claude-sonnet-4-5-thinking-medium`	Sonnet with 16K thinking budget
`google/antigravity-claude-sonnet-4-5-thinking-high`	Sonnet with 32K thinking budget
`google/antigravity-claude-opus-4-5-thinking-low`	Opus with 8K thinking budget
`google/antigravity-claude-opus-4-5-thinking-medium`	Opus with 16K thinking budget
`google/antigravity-claude-opus-4-5-thinking-high`	Opus with 32K thinking budget

Gemini CLI Quota

Models without antigravity- prefix use Gemini CLI quota:

Model	Description
`google/gemini-2.5-flash`	Gemini 2.5 Flash
`google/gemini-2.5-pro`	Gemini 2.5 Pro
`google/gemini-3-flash`	Gemini 3 Flash
`google/gemini-3-pro-low`	Gemini 3 Pro with low thinking
`google/gemini-3-pro-high`	Gemini 3 Pro with high thinking

Full models configuration

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": [
    "opencode-antigravity-auth@latest"
  ],
  "provider": {
    "google": {
      "models": {
        "antigravity-gemini-3-pro-low": {
          "name": "Gemini 3 Pro Low (Antigravity)",
          "limit": { "context": 1048576, "output": 65535 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-gemini-3-pro-high": {
          "name": "Gemini 3 Pro High (Antigravity)",
          "limit": { "context": 1048576, "output": 65535 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-gemini-3-flash": {
          "name": "Gemini 3 Flash (Antigravity)",
          "limit": { "context": 1048576, "output": 65536 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5": {
          "name": "Claude Sonnet 4.5 (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-low": {
          "name": "Claude Sonnet 4.5 Think Low (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-medium": {
          "name": "Claude Sonnet 4.5 Think Medium (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-sonnet-4-5-thinking-high": {
          "name": "Claude Sonnet 4.5 Think High (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-low": {
          "name": "Claude Opus 4.5 Think Low (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-medium": {
          "name": "Claude Opus 4.5 Think Medium (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        },
        "antigravity-claude-opus-4-5-thinking-high": {
          "name": "Claude Opus 4.5 Think High (Antigravity)",
          "limit": { "context": 200000, "output": 64000 },
          "modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
        }
      }
    }
  }
}

Configuration

Environment Overrides

OPENCODE_ANTIGRAVITY_QUIET=1         # quiet_mode
OPENCODE_ANTIGRAVITY_DEBUG=1         # debug
OPENCODE_ANTIGRAVITY_LOG_DIR=/path   # log_dir
OPENCODE_ANTIGRAVITY_KEEP_THINKING=1 # keep_thinking

Create `~/.config/opencode/antigravity.json` (or `.opencode/antigravity.json` in project root):

{
  // JSON Schema for IDE autocompletion
  "$schema": "https://raw.githubusercontent.com/anthropics/opencode-antigravity-auth/main/assets/antigravity.schema.json",

  // === General ===
  "quiet_mode": false,           // Suppress toast notifications (except recovery)
  "debug": false,                // Enable debug logging to file
  "log_dir": "/custom/log/path", // Custom debug log directory (optional)
  "auto_update": true,           // Auto-update plugin

  // === Thinking Blocks ===
  "keep_thinking": false,        // Preserve thinking blocks (may cause signature errors)

  // === Session Recovery ===
  "session_recovery": true,      // Auto-recover from tool_result_missing errors
  "auto_resume": true,           // Auto-send "continue" after recovery
  "resume_text": "continue",     // Custom resume prompt text

  // === Empty Response Handling ===
  "empty_response_max_attempts": 4,      // Max retries for empty responses
  "empty_response_retry_delay_ms": 2000, // Delay between retries (ms)

  // === Tool Handling ===
  "tool_id_recovery": true,       // Fix mismatched tool IDs from context compaction
  "claude_tool_hardening": true,  // Prevent Claude tool hallucinations

  // === Token Refresh ===
  "proactive_token_refresh": true,              // Background token refresh
  "proactive_refresh_buffer_seconds": 1800,     // Refresh 30min before expiry
  "proactive_refresh_check_interval_seconds": 300, // Check every 5min

  // === Rate Limiting ===
  "max_rate_limit_wait_seconds": 300, // Max wait time when rate limited (0=unlimited)
  "quota_fallback": false,            // Try alternate quota when rate limited

  // === Signature Cache (for keep_thinking=true) ===
  "signature_cache": {
    "enabled": true,
    "memory_ttl_seconds": 3600,      // 1 hour in-memory
    "disk_ttl_seconds": 172800,      // 48 hours on disk
    "write_interval_seconds": 60     // Background write interval
  }
}

Multi-Account Setup

Add multiple Google accounts for higher combined quotas. The plugin automatically rotates between accounts when one is rate-limited.

# Add accounts
opencode auth login

Compatible Plugins

This plugin works alongside other OpenCode plugins. Some important notes:

Plugin Ordering

If using @tarquinen/opencode-dcp (Dynamic Context Protocol), our plugin must be listed first:

{
  "plugins": [
    "opencode-antigravity-auth@latest",
    "@tarquinen/opencode-dcp@1.1.2"
  ]
}

Plugins You Don't Need

gemini-auth plugins - Not needed. This plugin handles all Google OAuth authentication.

Rate Limit Considerations

oh-my-opencode - This plugin may make background API calls that consume your quota. If you're hitting rate limits unexpectedly, check if oh-my-opencode is making requests.

Migration Guide (v1.2.7+)

If upgrading from v1.2.6 or earlier, follow these steps:

Step 1: Clear Old Tokens

rm -rf ~/.config/opencode/antigravity-tokens/

Step 2: Update opencode.json

Replace your old config with:

{
  "plugins": ["opencode-antigravity-auth@latest"],
  "provider": "google",
  "model": "google/antigravity-gemini-3-flash"
}

Step 3: Create antigravity.json (Optional)

If you had custom settings, migrate them to ~/.config/opencode/antigravity.json:

{
  "$schema": "https://raw.githubusercontent.com/anthropics/opencode-antigravity-auth/main/assets/antigravity.schema.json",
  "quiet_mode": false,
  "debug": false
}

Step 4: Re-authenticate

Run OpenCode once. A browser window will open for Google OAuth:

opencode

Breaking Changes

Old (v1.2.6)	New (v1.2.7+)
`OPENCODE_ANTIGRAVITY_*` env vars	`~/.config/opencode/antigravity.json`
`gemini-3-pro`	`google/antigravity-gemini-3-pro-low`
`claude-sonnet-4-5`	`google/antigravity-claude-sonnet-4-5`

E2E Testing

The plugin includes regression tests for stability verification. Tests consume API quota.

# Sanity tests (7 tests, ~5 min)
npx tsx script/test-regression.ts --sanity

# Heavy tests (4 tests, ~30 min) - stress testing with 8-50 turn conversations
npx tsx script/test-regression.ts --heavy

# Concurrent tests (3 tests) - rate limit handling with 5-10 parallel requests
npx tsx script/test-regression.ts --category concurrency

# Run specific test
npx tsx script/test-regression.ts --test thinking-tool-use

# List tests without running
npx tsx script/test-regression.ts --dry-run

Debugging

Enable debug logging:

# Via environment
OPENCODE_ANTIGRAVITY_DEBUG=1 opencode

# Via config
echo '{"debug": true}' > ~/.config/opencode/antigravity.json

Logs are written to ~/.config/opencode/antigravity-logs/ (or log_dir if configured).

Documentation

Architecture - Plugin internals and request flow
API Spec - Antigravity API reference

License

MIT