Google Antigravity IDE OAuth auth plugin for Opencode - access Gemini 3 Pro and Claude 4.5 using Google credentials
npm install opencode-antigravity-auth-revived
Enable Opencode to authenticate against Antigravity (Google's IDE) via OAuth so you can use Antigravity rate limits and access models like gemini-3-pro and claude-opus-4-5-thinking with your Google credentials.
- Claude Opus 4.5, Sonnet 4.5 and Gemini 3 Pro/Flash via Google OAuth
- Multi-account support — add multiple Google accounts, auto-rotates 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 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 — works alongside other OpenCode plugins (oh-my-opencode, dcp, etc.)
---
For Humans
Option A: Let an LLM do it
Paste this into any LLM agent (Claude Code, OpenCode, Cursor, etc.):
``
Install the opencode-antigravity-auth plugin and add the Antigravity model definitions to ~/.config/opencode/opencode.json by following: https://raw.githubusercontent.com/NoeFabris/opencode-antigravity-auth/dev/README.md
Option B: Manual setup
1. Add the plugin to ~/.config/opencode/opencode.json:
`json`
{
"plugin": ["opencode-antigravity-auth@latest"]
}
> Want bleeding edge features? Use opencode-antigravity-auth@beta instead.
2. Login with your Google account:
`bash`
opencode auth login
3. Add models — copy the full configuration below
4. Use it:
`bash`
opencode run "Hello" --model=google/antigravity-claude-sonnet-4-5-thinking --variant=max
For LLM Agents
1. Edit the OpenCode configuration file:
- Linux/Mac: ~/.config/opencode/opencode.json
- Windows:
2. Add the plugin to the plugins array:`
json`
{
"plugin": ["opencode-antigravity-auth@latest"]
}
3. Add the model definitions from the Full models configuration section
4. Set provider to "google" and choose a model
`bash`
opencode run "Hello" --model=google/antigravity-claude-sonnet-4-5-thinking --variant=max
---
Antigravity quota (Claude + Gemini 3):
| Model | Variants | Notes |
|-------|----------|-------|
| antigravity-gemini-3-pro | low, high | Gemini 3 Pro with thinking |antigravity-gemini-3-flash
| | minimal, low, medium, high | Gemini 3 Flash with thinking |antigravity-claude-sonnet-4-5
| | — | Claude Sonnet 4.5 |antigravity-claude-sonnet-4-5-thinking
| | low, max | Claude Sonnet with extended thinking |antigravity-claude-opus-4-5-thinking
| | low, max | Claude Opus with extended thinking |
Gemini CLI quota (separate from Antigravity):
| Model | Notes |
|-------|-------|
| gemini-2.5-flash | Gemini 2.5 Flash |gemini-2.5-pro
| | Gemini 2.5 Pro |gemini-3-flash-preview
| | Gemini 3 Flash (preview) |gemini-3-pro-preview
| | Gemini 3 Pro (preview) |
Using variants:
`bash`
opencode run "Hello" --model=google/antigravity-claude-sonnet-4-5-thinking --variant=max
For details on variant configuration and thinking levels, see docs/MODEL-VARIANTS.md.
Full models configuration (copy-paste ready)
Add this to your ~/.config/opencode/opencode.json:
`json`
{
"$schema": "https://opencode.ai/config.json",
"plugin": ["opencode-antigravity-auth@latest"],
"provider": {
"google": {
"models": {
"antigravity-gemini-3-pro": {
"name": "Gemini 3 Pro (Antigravity)",
"limit": { "context": 1048576, "output": 65535 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] },
"variants": {
"low": { "thinkingLevel": "low" },
"high": { "thinkingLevel": "high" }
}
},
"antigravity-gemini-3-flash": {
"name": "Gemini 3 Flash (Antigravity)",
"limit": { "context": 1048576, "output": 65536 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] },
"variants": {
"minimal": { "thinkingLevel": "minimal" },
"low": { "thinkingLevel": "low" },
"medium": { "thinkingLevel": "medium" },
"high": { "thinkingLevel": "high" }
}
},
"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": {
"name": "Claude Sonnet 4.5 Thinking (Antigravity)",
"limit": { "context": 200000, "output": 64000 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] },
"variants": {
"low": { "thinkingConfig": { "thinkingBudget": 8192 } },
"max": { "thinkingConfig": { "thinkingBudget": 32768 } }
}
},
"antigravity-claude-opus-4-5-thinking": {
"name": "Claude Opus 4.5 Thinking (Antigravity)",
"limit": { "context": 200000, "output": 64000 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] },
"variants": {
"low": { "thinkingConfig": { "thinkingBudget": 8192 } },
"max": { "thinkingConfig": { "thinkingBudget": 32768 } }
}
},
"gemini-2.5-flash": {
"name": "Gemini 2.5 Flash (Gemini CLI)",
"limit": { "context": 1048576, "output": 65536 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
},
"gemini-2.5-pro": {
"name": "Gemini 2.5 Pro (Gemini CLI)",
"limit": { "context": 1048576, "output": 65536 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
},
"gemini-3-flash-preview": {
"name": "Gemini 3 Flash Preview (Gemini CLI)",
"limit": { "context": 1048576, "output": 65536 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
},
"gemini-3-pro-preview": {
"name": "Gemini 3 Pro Preview (Gemini CLI)",
"limit": { "context": 1048576, "output": 65535 },
"modalities": { "input": ["text", "image", "pdf"], "output": ["text"] }
}
}
}
}
}
---
Add multiple Google accounts for higher combined quotas. The plugin automatically rotates between accounts when one is rate-limited.
`bash`
opencode auth login # Run again to add more accounts
For details on load balancing, dual quota pools, and account storage, see docs/MULTI-ACCOUNT.md.
---
DCP creates synthetic assistant messages that lack thinking blocks. List this plugin BEFORE DCP:
`json`
{
"plugin": [
"opencode-antigravity-auth@latest",
"@tarquinen/opencode-dcp@latest"
]
}
Disable built-in auth and override agent models in oh-my-opencode.json:
`json`
{
"google_auth": false,
"agents": {
"frontend-ui-ux-engineer": { "model": "google/antigravity-gemini-3-pro" },
"document-writer": { "model": "google/antigravity-gemini-3-flash" },
"multimodal-looker": { "model": "google/antigravity-gemini-3-flash" }
}
}
> Tip: When spawning parallel subagents, enable pid_offset_enabled: true in antigravity.json to distribute sessions across accounts.
- gemini-auth plugins — Not needed. This plugin handles all Google OAuth.
---
Create ~/.config/opencode/antigravity.json for advanced settings:
`json`
{
"$schema": "https://raw.githubusercontent.com/NoeFabris/opencode-antigravity-auth/main/assets/antigravity.schema.json",
"quiet_mode": false,
"debug": false
}
| Option | Default | What it does |
|--------|---------|--------------|
| quiet_mode | false | Hide toast notifications |debug
| | false | Enable debug logging |session_recovery
| | true | Auto-recover from tool errors |auto_resume
| | true | Auto-send "continue" after recovery |web_search.default_mode
| | "off" | Google Search grounding: "auto" or "off" |
For all options, see docs/CONFIGURATION.md.
Environment variables:
`bash``
OPENCODE_ANTIGRAVITY_DEBUG=1 opencode # Enable debug logging
OPENCODE_ANTIGRAVITY_DEBUG=2 opencode # Verbose logging
---
See the full Troubleshooting Guide for solutions to common issues including:
- Auth problems and token refresh
- "Model not found" errors
- Session recovery
- Gemini CLI permission errors
- Safari OAuth issues
- Plugin compatibility
- Migration guides
---
- 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
---
If this plugin helps you, consider supporting its maintenance:
---
- opencode-gemini-auth by @jenslys
- CLIProxyAPI
MIT License. See LICENSE for details.
Legal
- Personal / internal development only
- Respect internal quotas and data handling policies
- Not for production services or bypassing intended limits
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
- Not affiliated with Google. This is an independent open-source project.
- "Antigravity", "Gemini", "Google Cloud", and "Google" are trademarks of Google LLC.