abilityai/nano-banana-image-generator

Nano Banana Image Generator

Generate images using Google's Gemini 3.1 Flash Image Preview model (codename: Nano Banana 2).

Quick Start

Generate a simple image:

bash ~/.claude/skills/nano-banana-image-generator/scripts/generate.sh "A red apple on white background" apple.png

Generate a 16:9 thumbnail:

python3 ~/.claude/skills/nano-banana-image-generator/scripts/generate_thumbnail.py "YouTube thumbnail showing AI agents" /tmp/thumb.png

Generate with custom output directory:

OUTPUT_DIR=/tmp bash ~/.claude/skills/nano-banana-image-generator/scripts/generate.sh "Sunset over mountains" sunset.png

Scripts

| Script | Purpose | Output | |--------|---------|--------| | scripts/generate.sh | General image generation | 1024x1024 PNG | | scripts/generate_thumbnail.py | 16:9 thumbnails | 1344x768 PNG | | scripts/generate_image.py | Python with aspect ratio control | Configurable |

Pricing & Limits

• Cost: $0.067 per image
• Free tier: 500 requests/day
• Generation time: ~22 seconds
• Resolution: 1024x1024 (square), 1344x768 (16:9)

Best Practices

For detailed prompt engineering and brand styling guidelines, see best_practices.md.

Critical Constraints

| Element | Maximum | |---------|---------| | Visual boxes/shapes | 10 maximum | | Text pieces/labels | 10 maximum | | Hierarchy levels | 3 maximum |

Prompt Structure

DO: Write narrative descriptions

Create a simple infographic with black background showing a central concept
with 4-5 supporting elements. Use white text, DM Sans font, bold titles.

DON'T: Use keyword lists

LinkedIn post, gradient, red, white, large text, 15 boxes, arrows everywhere

Brand Styling (Eugene's)

Include in prompts for brand consistency:

Use Eugene's brand style: black background (#000000), white text (#ffffff),
DM Sans font, bold 700 weight for titles, clean minimal design.

Use Cases

Perfect For:

• Social media infographics and carousels
• YouTube thumbnails
• Diagrams and technical documentation
• Product mockups
• Mobile-optimized content

Not Ideal For:

• Hyper-realistic photography
• Complex multi-font typography
• Fine detail technical renders

Environment Variables

• GOOGLE_API_KEY or GEMINI_API_KEY - API key (required)
• OUTPUT_DIR - Output directory (default: current directory)

Examples

Infographic:

bash scripts/generate.sh "Simple framework diagram with black background. CENTER: 'AI Agents' in large white text. SURROUNDING: 4 icons for Planning, Memory, Tools, Learning. DM Sans font, minimal design." agents_framework.png

Thumbnail:

python3 scripts/generate_thumbnail.py "Professional YouTube thumbnail: bold white text 'DEEP AGENTS' on dramatic black background with subtle blue glow, tech aesthetic" deep_agents_thumb.png