Awesome-omni-skill nano-banana-skill

Generates, edits, and restores images using Google Gemini image models (Nano Banana). Use when the user wants to create images from text prompts, edit existing images with natural language, restore or enhance photos, or generate icons, patterns, diagrams, or visual content. Requires a GEMINI_API_KEY environment variable.

install

source · Clone the upstream repo

git clone https://github.com/diegosouzapw/awesome-omni-skill

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/diegosouzapw/awesome-omni-skill "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/backend/nano-banana-skill" ~/.claude/skills/diegosouzapw-awesome-omni-skill-nano-banana-skill && rm -rf "$T"

manifest: skills/backend/nano-banana-skill/SKILL.md

safety · automated scan (low risk)

This is a pattern-based risk scan, not a security review. Our crawler flagged:

references API keys

Always read a skill's source content before installing. Patterns alone don't mean the skill is malicious — but they warrant attention.

source content

Nano Banana Skill

Image generation, editing, and restoration powered by Google Gemini.

Setup (One-Time)

Run the setup script to install dependencies automatically:

bash <skill-dir>/scripts/setup.sh

Then set an API key (get one at https://aistudio.google.com/apikey):

export GEMINI_API_KEY="your-api-key"

The API key can be set as any of these environment variables (checked in order):

NANOBANANA_GEMINI_API_KEY

NANOBANANA_GOOGLE_API_KEY

GEMINI_API_KEY

GOOGLE_API_KEY

Quick Reference

Mode Purpose Required Flags

generate

Create image from text

--prompt

edit

Modify an existing image

--input

--prompt

restore

Enhance/fix an image

--input

Flag	Description	Default
`--prompt`	Text description of desired image	—
`--input`	Input image path (edit/restore)	—
`--reference`	Style reference image(s), repeatable	—
`--output`	Output file path	Auto-named
`--size`	`1K` , `2K` , or `4K`	`1K`
`--format`	`png` or `jpeg`	`png`
`--preview`	Open image after generation	off
`--json`	Output structured JSON	off

Generate Images

Create images from text prompts:

# Basic generation
python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "A banana floating in space"

# With specific size and format
python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "Cyberpunk cityscape at night" --size 2K --format jpeg

# With explicit output path
python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "Minimalist logo" --output ./my-logo.png

When

--output

is omitted, files are saved to

./nanobanana-output/

with auto-generated names based on the prompt.

Edit Images

Modify existing images using natural language instructions:

# Change style
python3 <skill-dir>/scripts/nanobanana.py --mode edit --input photo.jpg --prompt "Convert to watercolor painting style"

# Modify content
python3 <skill-dir>/scripts/nanobanana.py --mode edit --input scene.png --prompt "Add a rainbow in the sky"

# Change colors
python3 <skill-dir>/scripts/nanobanana.py --mode edit --input logo.png --prompt "Change the color scheme to blue and gold"

Restore Images

Enhance, repair, or upscale images:

# Auto-restore (uses default restoration prompt)
python3 <skill-dir>/scripts/nanobanana.py --mode restore --input old_photo.jpg

# Targeted restoration
python3 <skill-dir>/scripts/nanobanana.py --mode restore --input damaged.png --prompt "Remove scratches and improve sharpness"

# Enhance quality
python3 <skill-dir>/scripts/nanobanana.py --mode restore --input blurry.jpg --prompt "Enhance clarity and increase detail" --size 4K

Reference Images

Use reference images to guide the style of generated images:

# Single reference
python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "A mountain landscape" --reference style_guide.png

# Multiple references
python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "Product photo" --reference brand_style.png --reference color_palette.png

The script searches for input and reference files in these locations:

Current directory
```
./images/
```
```
./input/
```
```
./nanobanana-output/
```
```
~/Downloads/
```
```
~/Desktop/
```

Output

Smart Naming

When

--output

is omitted, files are automatically named based on the prompt text:

Prompt is converted to lowercase with special characters removed
Spaces become underscores, limited to 32 characters
Duplicate names get a numeric suffix (
```
_1
```
,
```
_2
```
, etc.)
All auto-named files go into
```
./nanobanana-output/
```

Sizes

Size	Description
`1K`	Standard resolution (default, fastest)
`2K`	High resolution
`4K`	Maximum resolution (slowest)

Model Selection

Set the

NANOBANANA_MODEL

environment variable to choose a model:

# Default model (fast, good quality)
export NANOBANANA_MODEL="gemini-2.5-flash-image"

# Pro model (highest quality)
export NANOBANANA_MODEL="gemini-3-pro-image-preview"

If unset, defaults to

gemini-2.5-flash-image

Specialized Patterns

No special flags are needed for these -- just use descriptive prompts:

Icons

python3 <skill-dir>/scripts/nanobanana.py --mode generate \
  --prompt "Flat design app icon for a weather app, rounded corners, minimal style, solid background" \
  --size 1K

Patterns

python3 <skill-dir>/scripts/nanobanana.py --mode generate \
  --prompt "Seamless tileable geometric pattern, blue and white, high density, suitable for fabric print"

Diagrams

python3 <skill-dir>/scripts/nanobanana.py --mode generate \
  --prompt "Architecture diagram showing microservices: API gateway, auth service, user service, database. Clean lines, labeled boxes"

Sequential / Story Images

Generate each frame as a separate call, referencing previous outputs to maintain visual consistency:

# Frame 1
python3 <skill-dir>/scripts/nanobanana.py --mode generate \
  --prompt "Scene 1 of 3: A hero stands at the edge of a forest, sunrise, cinematic style" \
  --output ./nanobanana-output/story_1.png

# Frame 2 (reference previous for consistency)
python3 <skill-dir>/scripts/nanobanana.py --mode generate \
  --prompt "Scene 2 of 3: The same hero enters the forest, dappled light, cinematic style" \
  --reference ./nanobanana-output/story_1.png \
  --output ./nanobanana-output/story_2.png

Preview

Add

--preview

to automatically open the generated image:

python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "Sunset over ocean" --preview

Uses the system default image viewer (macOS:

open

, Linux:

xdg-open

, Windows:

start

JSON Output

Add

--json

for structured output suitable for agent parsing:

python3 <skill-dir>/scripts/nanobanana.py --mode generate --prompt "A banana" --json

Output format:

{
  "success": true,
  "files": ["nanobanana-output/a_banana.png"],
  "message": "Image generated successfully."
}

On failure:

{
  "success": false,
  "files": [],
  "message": "Error description here"
}

Error Handling

Error	Cause	Fix
No API key found	Missing environment variable	Set `GEMINI_API_KEY`
403 / Permission denied	Invalid API key	Check key at https://aistudio.google.com/apikey
429 / Rate limit	Too many requests	Wait and retry
Safety filter	Prompt flagged	Rephrase the prompt
No image generated	Model returned text only	Try a more specific prompt
File not found	Input/reference image missing	Check path or place in a searched directory

See

references/ADVANCED.md

for advanced prompt engineering patterns, model comparison, and troubleshooting.