nanobanana

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha a5004a4238e6 · 28 Oct 2026Report an issue or request a re-scan

• Publisherresciencelab GitHub organizationOwner of the repository this skill is read from
• Source folderresciencelab/opc-skills/skills/nanobananaThe exact folder we audited
• LicenceApache-2.0As the repository states it
• Commit pinned for this verdicta5004a4238e6A new audit runs when the source changes
• Repository statusNot archivedPushed today
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Generate and edit images using Google Gemini 3 Pro Image (Nano Banana Pro). Supports text-to-image, image editing, various aspect ratios, and high-resolution output (2K/4K). Use when user wants to generate images,…

---
name: nanobanana
description: Generate and edit images using Google Gemini 3 Pro Image (Nano Banana Pro). Supports text-to-image, image editing, various aspect ratios, and high-resolution output (2K/4K). Use when user wants to generate images, create images, use Gemini image generation, or do AI image generation.
---

# Nano Banana - AI Image Generation

Generate and edit images using Google's Gemini 3 Pro Image model (`gemini-3-pro-image-preview`, nicknamed "Nano Banana Pro" 🍌).

## Prerequisites

**Required:**
- `GEMINI_API_KEY` - Get from [Google AI Studio](https://aistudio.google.com/apikey)
- Python 3.10+ with `google-genai` package

**Install dependencies:**
```bash
pip install google-genai pillow
```

## Quick Start

### Generate an image:
```bash
python3 <skill_dir>/scripts/generate.py "a cute robot mascot, pixel art style" -o robot.png
```

### Edit an existing image:
```bash
python3 <skill_dir>/scripts/generate.py "make the background blue" -i input.jpg -o output.png
```

### Generate with specific aspect ratio:
```bash
python3 <skill_dir>/scripts/generate.py "cinematic landscape" --ratio 21:9 -o landscape.png
```

### Generate high-resolution 4K image:
```bash
python3 <skill_dir>/scripts/generate.py "professional product photo" --size 4K -o product.png
```

## Script Reference

### `scripts/generate.py`

Main image generation script.

```
Usage: generate.py [OPTIONS] PROMPT

Arguments:
  PROMPT              Text prompt for image generation

Options:
  -o, --output PATH   Output file path (default: auto-generated)
  -i, --input PATH    Input image for editing (optional)
  -r, --ratio RATIO   Aspect ratio (1:1, 16:9, 9:16, 21:9, etc.)
  -s, --size SIZE     Image size: 2K or 4K (default: standard)
  --search            Enable Google Search grounding for accuracy
  -v, --verbose       Show detailed output
```

**Supported aspect ratios:**
- `1:1` - Square (default)
- `2:3`, `3:2` - Portrait/Landscape
- `3:4`, `4:3` - Standard
- `4:5`, `5:4` - Photo
- `9:16`, `16:9` - Widescreen
- `21:9` - Ultra-wide/Cinematic

### `scripts/batch_generate.py`

Generate multiple images with sequential naming.

```
Usage: batch_generate.py [OPTIONS] PROMPT

Arguments:
  PROMPT              Text prompt for image generation

Options:
  -n, --count N       Number of images to generate (default: 10)
  -d, --dir PATH      Output directory
  -p, --prefix STR    Filename prefix (default: "image")
  -r, --ratio RATIO   Aspect ratio
  -s, --size SIZE     Image size (2K/4K)
  --delay SECONDS     Delay between generations (default: 3)
```

**Example:**
```bash
python3 <skill_dir>/scripts/batch_generate.py "pixel art logo" -n 20 -d ./logos -p logo
```

## Python API

You can also use the module directly:

```python
from generate import generate_image, edit_image

# Generate image
result = generate_image(
    prompt="a futuristic city at night",
    output_path="city.png",
    aspect_ratio="16:9",
    image_size="4K"
)

# Edit existing image
result = edit_image(
    prompt="add flying cars to the sky",
    input_path="city.png",
    output_path="city_edited.png"
)
```

## Environment Variables

| Variable | Description | Default |
|----------|-------------|---------|
| `GEMINI_API_KEY` | Google Gemini API key | Required |
| `IMAGE_OUTPUT_DIR` | Default output directory | `./nanobanana-images` |

## Features

### Text-to-Image Generation
Create images from text descriptions. The model excels at:
- Photorealistic images
- Artistic styles (pixel art, illustration, etc.)
- Product photography
- Landscapes and scenes

### Image Editing
Transform existing images with natural language:
- Style transfer
- Object addition/removal
- Background changes
- Color adjustments

### High-Resolution Output
- **Standard**: Fast generation, good quality
- **2K**: Enhanced detail (2048px)
- **4K**: Maximum quality (3840px), best for text rendering

### Google Search Grounding
Enable `--search` for factually accurate images involving:
- Real people, places, landmarks
- Current events
- Specific products or brands

## Best Practices

### Prompt Writing

**Good prompts include:**
- Subject description
- Style/aesthetic
- Lighting and mood
- Composition details
- Color palette

**Example:**
```
"A cozy coffee shop interior, warm lighting, vintage aesthetic, 
wooden furniture, plants on shelves, morning sunlight through windows, 
soft focus background, 35mm film photography style"
```

### Batch Generation Tips

1. Generate 10-20 variations to explore options
2. Use consistent prompts for style coherence
3. Add 3-5 second delays to avoid rate limits
4. Review results and iterate on best candidates

## Rate Limits

- Gemini API has usage quotas
- Add delays between batch generations
- Check your quota at [Google AI Studio](https://aistudio.google.com/)

## Troubleshooting

**"API key not found"**
- Set `GEMINI_API_KEY` environment variable
- Or pass via `--api-key` option

**"No image in response"**
- Prompt may have triggered safety filters
- Try rephrasing to avoid sensitive content

**"Rate limit exceeded"**
- Wait a few seconds and retry
- Reduce batch size or add longer delays

## References

- [references/prompts.md](./references/prompts.md) - Prompt examples by category
- [examples/](./examples/) - Example usage scripts

Excerpt, first 5,278 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

pip install google-genai pillow

git clone https://github.com/resciencelab/opc-skills
git -C opc-skills checkout a5004a4238e6

Works in

1. 2026-10-28
   ✓SAFE B 89 / 100

   first audit · source a5004a4238e6

Questions about nanobanana

• github.com/resciencelab/opc-skills/tree/main/skills/nanobanana — the audited source at commit a5004a4238e6 and every finding aboveObserved · 28 Oct 2026

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