opencode-antigravity-img

OpenCode plugin for generating images using Gemini 3 Pro Image model via Google's Antigravity/CloudCode API.

Requirements

• OpenCode installed
• Google One AI Premium subscription
• Authentication via opencode-antigravity-auth plugin

Installation

1. First, install and configure the authentication plugin:

# Add to your opencode.json
"plugin": [
  "opencode-antigravity-auth",
  "opencode-antigravity-img"
]

2. Run the auth plugin to authenticate with your Google account:

opencode
# Use the authenticate command from antigravity-auth

This creates antigravity-accounts.json in your opencode config directory.

Multi-Account Setup

You can add multiple Google accounts for higher throughput and automatic failover:

opencode auth login  # repeat for each Google account

With multiple accounts the plugin will:

• Round-robin between accounts, picking the least-recently-used one
• Auto-retry with the next account if one fails (rate-limit, auth error, etc.)
• Track cooldowns so rate-limited accounts are skipped for 5 minutes
• Show per-account quota via the image_quota tool

Single-account users see no behavior change.

Tools

generate_image

Generate an image from a text prompt.

Arguments:

• prompt (required): Text description of the image to generate
• filename (optional): Output filename (default: generated_<timestamp>.jpg)
• output_dir (optional): Output directory (default: current working directory)
• aspect_ratio (optional): Image aspect ratio. Supported values: 1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9 (default: 1:1)
• image_size (optional): Image resolution. Supported values: 1K, 2K, 4K (default: 1K)

Example:

Generate a 16:9 landscape image of a sunset over mountains with a lake in the foreground

Output:

• Image file saved to specified path
• Returns path, size, format, and remaining quota

image_quota

Check the remaining quota for the Gemini 3 Pro Image model.

Arguments: None

Output (single account):

• Visual progress bar showing remaining quota percentage
• Time until quota resets

Output (multi-account):

• Per-account progress bars with quota percentage
• Rate-limit status per account
• Time until reset for each account

Image Details

• Model: Gemini 3 Pro Image
• Resolutions:
  • 1K: 1024x1024 (default)
  • 2K: 2048x2048
  • 4K: 4096x4096
• Aspect ratios: 1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9
• Format: JPEG (always, regardless of filename extension)
• Generation time: 10-30 seconds

Unsupported Parameters

The following parameters are documented in Google's API but are not supported by the Gemini 3 Pro Image model (they are Imagen-specific):

• personGeneration - Control generation of people in images
• outputMimeType - Output format selection (always returns JPEG)
• compressionQuality - JPEG compression control

These parameters may work with Imagen models but have no effect with Gemini 3 Pro Image.

Quota

Image generation uses a separate quota from text models. The quota resets every 5 hours. Use the image_quota tool (or the /antigravity-quota-img command) to check your remaining quota.

With multiple accounts, each account has its own independent quota. The plugin automatically rotates to the account with the most available quota.

Troubleshooting

"No Antigravity account found"

Make sure you've:

1. Installed opencode-antigravity-auth
2. Authenticated with your Google account
3. The credentials file antigravity-accounts.json exists in your opencode config directory

"Rate limited" or generation fails

• With multiple accounts, the plugin automatically retries with the next available account
• Check your quota with image_quota to see per-account status
• If all accounts are exhausted, wait a few minutes for cooldowns to expire
• The plugin also tries multiple API endpoints per account

Slow generation

Image generation typically takes 10-30 seconds. This is normal due to the complexity of image synthesis.

API Endpoints

The plugin uses Google's CloudCode API with fallback endpoints:

1. https://daily-cloudcode-pa.googleapis.com (primary)
2. https://daily-cloudcode-pa.sandbox.googleapis.com (fallback)
3. https://cloudcode-pa.googleapis.com (production)

Related Plugins

• opencode-antigravity-auth - Authentication (required)
• opencode-antigravity-web - Web search and URL reading

License

MIT