Nano Banana Image Generation

Generate high-quality images using Google's Gemini 3 Pro Image Preview model via OpenRouter.

Setup

The .env file is already configured with the API key. Scripts are located at:

•Bash: .cursor/skills/nano-banana/scripts/nano-banana.sh
•Node.js: .cursor/skills/nano-banana/scripts/nano-banana.js

Quick Start

Run from the project root directory:

Generate a new image

bash

.cursor/skills/nano-banana/scripts/nano-banana.sh "A modern minimalist logo, blue gradient" -o logo.png

Edit an existing image

bash

.cursor/skills/nano-banana/scripts/nano-banana.sh "Make the background darker" -i image.png -o edited.png

Use multiple reference images

bash

.cursor/skills/nano-banana/scripts/nano-banana.sh "Combine styles" -i ref1.png -i ref2.png -o combined.png

CLI Options

Option	Description
`-o`, `--output`	Output path for generated image
`-i`, `--input`	Input image(s) for editing (can specify multiple)
`-m`, `--model`	Model ID (default: google/gemini-3-pro-image-preview)

Common Use Cases

Website Assets

bash

# Favicon
.cursor/skills/nano-banana/scripts/nano-banana.sh "Minimalist favicon, letter S, modern tech style" -o public/favicon.png

# Hero image
.cursor/skills/nano-banana/scripts/nano-banana.sh "Abstract gradient hero, purple to blue" -o public/hero.png

# Social preview
.cursor/skills/nano-banana/scripts/nano-banana.sh "Social media preview card, 1200x630" -o public/og-image.png

Icons

bash

.cursor/skills/nano-banana/scripts/nano-banana.sh "Minimalist line icon for home" -o assets/icons/home.png
.cursor/skills/nano-banana/scripts/nano-banana.sh "Minimalist line icon for mail" -o assets/icons/mail.png

Image Editing

bash

# Remove background
.cursor/skills/nano-banana/scripts/nano-banana.sh "Remove background, make transparent" -i photo.jpg -o photo-nobg.png

# Style transfer
.cursor/skills/nano-banana/scripts/nano-banana.sh "Apply cyberpunk neon aesthetic" -i original.png -o styled.png

Node.js Programmatic Use

javascript

const { generateImage } = require('./.cursor/skills/nano-banana/scripts/nano-banana.js');

await generateImage({
  prompt: "A beautiful sunset over mountains",
  outputPath: "assets/sunset.png",
  inputPaths: [] // optional reference images
});

Troubleshooting

OPENROUTER_API_KEY not set

•The .env file should exist in project root with the key

No image in response

•Rephrase prompt to explicitly request image generation
•Prefix with "Generate an image of..."

Model not available

•Try fallback: -m google/gemini-2.0-flash-exp:free