nano-banana

name	nano-banana
description	Generate images using Google's Nano-Banana (Gemini 2.5 Flash Image) model. Use when the user asks to generate, create, or make an image, picture, or illustration.
allowed-tools	Read, Bash

Nano-Banana Image Generation

Generate images using Google's Gemini Image models.

IMPORTANT: Enhance User Prompts

Before generating, always enhance the user's prompt using the techniques in PROMPTING.md.

Quick Enhancement Formula

[Subject] + [Style] + [Lighting] + [Composition] + [Quality]

Example Enhancement

• User says: "a cat"
• Enhanced: "A fluffy orange tabby cat with bright green eyes, photorealistic, soft natural window lighting, shallow depth of field, rule of thirds composition"

For detailed prompting techniques, templates, and style keywords, see PROMPTING.md.

Quick Start

~/.claude/skills/nano-banana/scripts/generate.sh "your prompt here"

Options

Option	Description	Default
--output PATH	Save to specific file	~/Pictures/nano-banana/<timestamp>.png
--size SIZE	Resolution: 1K, 2K, 4K	1K
--aspect RATIO	Aspect ratio	1:1
--flash	Use Flash model (faster, lower quality)	Pro

Aspect Ratios

1:1, 16:9, 9:16, 4:3, 3:4, 3:2, 2:3

Resolutions

• 1K - Standard (default, fast)
• 2K - High resolution (requires Pro model)
• 4K - Maximum resolution (requires Pro model)

Interpreting User Requests

Parse the user's request and map to script options:

User says	Script call
"Generate a cat"	generate.sh "a cat"
"Create a 4K image of mountains"	generate.sh "mountains" --size 4K
"Make a landscape wallpaper"	generate.sh "landscape" --aspect 16:9
"High quality portrait of a robot"	generate.sh "portrait of a robot" --pro --aspect 3:4
"Generate a sunset, save to desktop"	generate.sh "a sunset" --output ~/Desktop/sunset.png
"4K widescreen cyberpunk city"	generate.sh "cyberpunk city" --size 4K --aspect 16:9

Keywords to watch for:

• Resolution: "4K", "high res", "high resolution", "2K", "large" → use --size
• Quality: "high quality", "detailed", "professional" → use --pro
• Orientation: "landscape", "widescreen", "wallpaper" → --aspect 16:9
• Orientation: "portrait", "vertical", "phone wallpaper" → --aspect 9:16
• Save location: "save to", "put it in", "output to" → --output

Behavior

• Runs in background (won't block Claude)
• Sends macOS notification when complete
• Auto-opens the image when done
• Images saved to ~/Pictures/nano-banana/ by default

Troubleshooting

Check the error log:

cat ~/.claude/skills/nano-banana/last-error.log

Verify API key:

security find-generic-password -a "$USER" -s "GEMINI_API_KEY" -w | head -c 10