| name | image |
| description | Generate and edit images using AI models via OpenRouter. Supports Nano Banana Pro (Gemini 3 Pro Image), FLUX, and other image generation models. |
| allowed-tools | ["Read","Write","Edit","Bash"] |
Nano Banana - Image Generation
Overview
Generate and edit images using state-of-the-art AI models. Perfect for creating visual assets, concept art, illustrations, and editing existing images.
Key Features:
- 🎨 Multiple Models: Gemini 3 Pro Image, FLUX Pro, and more
- ✏️ Image Editing: Modify existing images with natural language
- 🚀 Simple API: One command to generate or edit
- 💾 Automatic Saving: Handles file formats automatically
When to Use This Skill
Use this skill when you need:
- Visual Assets: Icons, illustrations, backgrounds
- Concept Art: Ideas and visual explorations
- Marketing Materials: Product mockups, social media images
- Photo Editing: Modify existing images with AI
- Creative Content: Artistic images, abstract visuals
- Presentation Graphics: Visuals for slides and documents
Note: For technical diagrams (architecture, flowcharts, ERD), use the diagram skill instead—it includes quality review and iteration.
Quick Start
python skills/image/scripts/generate_image.py "A beautiful sunset over mountains with orange and purple sky" -o sunset.png
python skills/image/scripts/generate_image.py "Make the sky more dramatic with storm clouds" --input sunset.png -o dramatic_sunset.png
python skills/image/scripts/generate_image.py "Abstract geometric art in blue and gold" -m "black-forest-labs/flux.2-pro" -o abstract.png
Available Models
| Model | ID | Capabilities | Best For |
|---|
| Gemini 3 Pro Image | google/gemini-3-pro-image-preview | Generation + Editing | High quality, versatile |
| FLUX Pro | black-forest-labs/flux.2-pro | Generation + Editing | Fast, artistic |
| FLUX Flex | black-forest-labs/flux.2-flex | Generation only | Development/testing |
Usage Examples
Generate New Images
python generate_image.py "Professional headshot of a business executive in modern office setting" -o headshot.png
python generate_image.py "Watercolor painting of a cozy coffee shop on a rainy day" -o coffee_shop.png
python generate_image.py "Abstract visualization of data flowing through neural networks, blue and cyan colors" -o neural_flow.png
python generate_image.py "Modern minimalist logo for a tech startup called 'Nexus', clean geometric design" -o logo.png
Edit Existing Images
python generate_image.py "Change the car color to red" --input car.jpg -o red_car.png
python generate_image.py "Add a rainbow in the sky" --input landscape.jpg -o rainbow_landscape.png
python generate_image.py "Remove the person from the background" --input photo.jpg -o clean_photo.png
python generate_image.py "Make this look like a watercolor painting" --input photo.jpg -o watercolor.png
Specify Output Format
python generate_image.py "Icon of a rocket ship" -o rocket.png
python generate_image.py "Banner image" -o assets/images/banner.png
Configuration
Environment Variable (Recommended)
export OPENROUTER_API_KEY='your_api_key_here'
.env File
Create a .env file in your project:
OPENROUTER_API_KEY=your_api_key_here
Get Your API Key
- Go to https://openrouter.ai/keys
- Create a new API key
- Add credits to your account
Python API
from skills.image.scripts.generate_image import generate_image
result = generate_image(
prompt="A futuristic city at night with neon lights",
output_path="city.png",
model="google/gemini-3-pro-image-preview"
)
result = generate_image(
prompt="Add flying cars to the scene",
output_path="city_with_cars.png",
input_image="city.png"
)
Tips for Better Images
Be Descriptive
"A dog"
"A golden retriever puppy playing in autumn leaves, warm afternoon sunlight, shallow depth of field, professional pet photography"
Include Style
"A mountain landscape in the style of traditional Japanese ink painting, minimalist, black and white with subtle gray tones"
Specify Composition
"Close-up portrait of an owl, centered composition, soft studio lighting, dark background, sharp focus on the eyes"
For Editing, Be Specific
"Make it better"
"Increase the contrast, make the colors more vibrant, and add a subtle vignette effect"
Comparison: image vs diagram Skills
| Aspect | image Skill | diagram Skill |
|---|
| Use Case | Photos, art, illustrations | Technical diagrams |
| Quality Review | No | Yes (Gemini 3 Pro) |
| Iteration | Single pass | Smart iteration (1-2 passes) |
| Doc Types | N/A | 13 document types with thresholds |
| Image Editing | Yes | No |
| Best For | Creative visuals | Architecture, flowcharts, ERD |
Rule of thumb: If it's a technical diagram with boxes, arrows, and labels → use diagram. If it's a photo, illustration, or artistic image → use image.
Troubleshooting
"OPENROUTER_API_KEY not found"
Set the environment variable or create a .env file. See Configuration section.
"Image file not found" (for editing)
Make sure the input image path is correct and the file exists.
Unexpected Output
- Try a different model
- Add more detail to your prompt
- Be more specific about style, composition, and colors
Generation Timeout
Large or complex images may take up to 2 minutes. Timeout is set to 120 seconds.
Cost Considerations
- Gemini 3 Pro Image: ~$2/M input, ~$12/M output tokens
- FLUX Pro: Check OpenRouter for current pricing
- Typical image generation: $0.02-0.10 per image
- Image editing: Similar to generation costs