| name | nano-banana |
| description | Generate or edit images using Nano Banana models (gemini-3.1-flash-lite-image, gemini-3.1-flash-image, gemini-3-pro-image, gemini-2.5-flash-image) with ADC auth. Supports "banana" as a verb (e.g., "please banana this") and Anime Dani / Chibi Dani character consistency. |
Nano Banana Skill
Generate, edit, and iterate on visuals conversationally using Google's native Nano Banana image generation models (gemini-3.1-flash-lite-image, gemini-3.1-flash-image, gemini-3-pro-image, gemini-2.5-flash-image) with Application Default Credentials (ADC) authentication.
Trigger Conditions
Activate this skill whenever the user asks to:
- Generate new images or illustrations from text descriptions.
- Edit, transform, style, or combine existing images.
- Use "banana" as a verb (e.g., "please banana this image", "banana me as an anime character", "banana this into chibi style").
- Generate character-consistent imagery featuring Anime Dani, Daniela, or Chibi Dani.
Model Selection & Capability Matrix
| Feature / Capability | Nano Banana 2 Lite (nano-banana-2-lite) | Nano Banana 2 (nano-banana-2) | Nano Banana Pro (nano-banana-pro) | Nano Banana Legacy (nano-banana) |
|---|
| Model ID | gemini-3.1-flash-lite-image | gemini-3.1-flash-image | gemini-3-pro-image | gemini-2.5-flash-image |
| Primary Use Case | High-velocity, budget-sensitive tasks | Generalist workhorse balance of speed & quality | Premium professional asset production | Legacy workhorse (transition to 2 Lite) |
| Supported Resolutions | 1K only | 512px (0.5K), 1K, 2K, 4K | 1K, 2K, 4K | 1024px (1K) |
| Object References | Up to 14 | Up to 10 | Up to 6 | Up to 3 |
| Character References | N/A | Up to 4 | Up to 5 | N/A |
| Style References | N/A | N/A | Up to 3 | N/A |
| Total Ref Images | Up to 14 | Up to 14 | Up to 14 | Up to 3 |
| Search Grounding | Not Supported | Web Search + Image Search | Web Search | Not Supported |
| Thinking Mode | Standard | minimal / high levels | Default thinking | N/A |
| Video Context | Not Supported | YouTube URLs & MP4 files | Not Supported | Not Supported |
| Interleaved Output | No | No | Supported (text + images) | No |
Model Selection Guide
- Nano Banana 2 Lite (
nano-banana-2-lite or nano-banana-lite): Default model. Ultra-fast, budget-conscious, high-volume generation (gemini-3.1-flash-lite-image). Ideal for rapid prototyping and high-velocity iteration.
- Nano Banana 2 (
nano-banana-2): The versatile, all-around workhorse (gemini-3.1-flash-image). Best for general tasks, multi-reference object/character composition, video-to-image, 4K output, and image search grounding.
- Nano Banana Pro (
nano-banana-pro): Premium model (gemini-3.1-pro-image). Use for complex visual reasoning, intricate text rendering, professional marketing assets, character consistency with style references, and interleaved story illustrations.
- Nano Banana (
nano-banana): Legacy pioneer model (gemini-2.5-flash-image). Transition users to Nano Banana 2 Lite for superior quality, lower cost, and lower latency.
Technical Specifications & Configuration
Resolution & Formatting Rules
- Resolution Parameter (
image_size): Must use uppercase 'K' (e.g. 512px, 1K, 2K, 4K). Lowercase values (e.g. 1k) will be rejected.
- SynthID Watermark: All generated images automatically include an imperceptible SynthID watermark.
Supported Aspect Ratios
- Nano Banana 2 Lite:
1:1, 3:2, 2:3, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9.
- Nano Banana 2:
1:1, 1:4, 1:8, 2:3, 3:2, 3:4, 4:1, 4:3, 4:5, 5:4, 8:1, 9:16, 16:9, 21:9.
- Nano Banana Pro:
1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9.
- Nano Banana Legacy:
1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9.
Character Consistency (Anime Dani, Daniela & Chibi Dani)
When generating or editing imagery featuring Anime Dani, Daniela, or Chibi Dani, attach the corresponding reference images from {baseDir}/references/ to enforce visual consistency.
Anime Dani / Daniela
- Style: Vibrant anime aesthetics, expressive eyes, crisp cel-shading, detailed linework.
- Reference Images: Pass
{baseDir}/references/speaker-dani.png and {baseDir}/references/celebrating-dani.png via -i.
Chibi Dani
- Style: Super-deformed (SD) kawaii chibi style, oversized head, cute proportions, simplified outlines.
- Reference Image: Pass
{baseDir}/references/chibi-dani.png via -i.
Prompting Strategies & Templates
Text-to-Image Generation
1. Photorealistic Scenes
- Template:
A photorealistic [type of shot] of a [subject description] in a [setting description]. [Lighting description]. Shot from a [camera angle] with a [lens type]. [Aspect ratio].
- Example:
A photorealistic wide-angle shot of a vibrant coral reef teeming with tropical fish. Crystal-clear turquoise water with sunbeams filtering down from the surface, illuminating a sea turtle gliding gracefully over the coral. Shot from a low perspective with a wide-angle lens. Aspect ratio 16:9.
2. Stylized Illustrations & Stickers
- Template:
A [style] of a [subject with details] doing [activity]. Features [bold outlines, cel-shading, etc.] and [color/background preference].
- Example:
A kawaii-style sticker of a happy red panda wearing a tiny bamboo hat, munching on a green bamboo leaf. Bold clean outlines, simple cel-shading, vibrant colors. Solid white background.
3. Accurate Text Rendering
- Template:
Create a [image type] for [brand/concept] with the text "[exact text]" in a [font style]. The design should be [style description], with a [color scheme].
- Example:
Create a modern minimalist logo for a coffee shop called 'The Daily Grind'. The text should be in a clean bold sans-serif font. Black and white color scheme inside a circle, incorporating a coffee bean.
4. Product Mockups & Commercial Photography
- Template:
A high-resolution studio-lit product photograph of a [product] on a [surface/background]. Lighting is [lighting setup] to [purpose]. Camera angle is [angle] with sharp focus on [key detail].
- Example:
A high-resolution studio-lit product photo of a minimalist matte black ceramic coffee mug on polished concrete. Three-point softbox lighting, soft diffused highlights. 45-degree angle shot with sharp focus on rising steam.
5. Minimalist & Negative Space Design
- Template:
A minimalist composition featuring a single [subject] positioned in the [corner/side]. The background is a vast, empty [color] canvas with negative space. Soft lighting.
- Example:
A minimalist composition featuring a delicate red maple leaf in the bottom-right frame. Vast empty off-white canvas with negative space for text overlay. Soft diffused light.
6. Sequential Art & Storyboarding
- Template:
Make a [N]-panel comic in a [art style] featuring [character/setting].
- Example:
Make a 3-panel comic in a gritty noir art style with high-contrast black and white inks showing a humorous detective scene.
7. Grounded Search Generation
- Usage: Enable
google_search tool to pull real-time weather, sporting events, or live data into visual graphics.
- Example:
Visualize the current 5-day weather forecast for San Francisco as a clean modern weather chart with attire suggestions for each day.
Image Editing & Multimodal Transformations
1. Adding and Removing Elements
- Template:
Using the provided image of [subject], please [add/remove/modify] [element]. Ensure the change [integration description].
- Example:
Using the provided image of my cat, please add a small knitted wizard hat on its head. Ensure it sits comfortably and matches the soft lighting.
2. Inpainting (Semantic Masking)
- Template:
Using the provided image, change only [specific element] to [new element]. Keep everything else in the image exactly the same, preserving original style and lighting.
- Example:
Using the provided image of a living room, change only the blue sofa to a vintage brown leather chesterfield sofa. Keep all other room elements unchanged.
3. Style Transfer
- Template:
Transform the provided photograph of [subject] into the artistic style of [artist/style]. Preserve the original composition but render with [stylistic details].
- Example:
Transform the provided photograph of a modern city street into the style of Van Gogh's Starry Night with swirling impasto brushstrokes and deep blue/yellow palette.
4. Advanced Multi-Image Composition
- Template:
Create a composite image combining elements from the provided images. Take [element from Image 1] and place it on/with [element from Image 2].
- Example:
Take the blue floral dress from the first image and have the woman from the second image wear it in an outdoor e-commerce fashion shot.
5. Sketch-to-Photo (Bringing Drawings to Life)
- Template:
Turn this rough [medium] sketch of a [subject] into a [style] photo. Keep [sketch lines/profile] but add [materials/lighting].
- Example:
Turn this rough pencil sketch of a futuristic car into a polished photo of a concept car in a showroom with metallic blue paint and neon rim lighting.
Professional Prompting Best Practices
- Be Hyper-Specific: Describe materials, lighting setups, camera lenses, and exact textures (e.g. "ornate elven plate armor etched with silver leaf patterns, high pauldrons shaped like falcon wings").
- Specify Intent & Context: Framing the purpose improves composition (e.g. "e-commerce product shot for high-end skincare" vs "bottle photo").
- Iterate Conversationally: Use multi-turn follow-ups to fine-tune details ("Keep everything the same, but make the background light warmer").
- Positive Framing for Negative Prompts: Instead of saying "no cars", describe the scene positively as "an empty, deserted street with no signs of traffic".
- Cinematic Camera Controls: Use photographic terms like
wide-angle shot, macro shot, low-angle perspective, three-point softbox setup.
Code Integration Guide (Google GenAI SDK)
Python SDK (google-genai)
from google import genai
import base64
client = genai.Client()
interaction = client.interactions.create(
model="gemini-3.1-flash-image",
input="A futuristic city inside a floating glass bottle in space",
generation_config={"thinking_level": "high"},
response_format={
"type": "image",
"aspect_ratio": "16:9",
"image_size": "2K"
}
)
with open("output.png", "wb") as f:
f.write(base64.b64decode(interaction.output_image.data))
Multimodal Image Editing with Base64
with open("input.png", "rb") as f:
img_bytes = f.read()
interaction = client.interactions.create(
model="gemini-3.1-flash-image",
input=[
{"type": "text", "text": "Add a glowing blue wizard hat to the cat"},
{
"type": "image",
"data": base64.b64encode(img_bytes).decode('utf-8'),
"mime_type": "image/png"
}
]
)
Usage & Execution via CLI
Note: {baseDir} refers to the root directory of the installed skill.
Use uv run to execute the image generation script at {baseDir}/scripts/banana.py.
CLI Arguments
-p, --prompt: Text prompt describing the image to generate or edit (required).-f, --filename: Output image filename (required).-i, --input-image: Path to input/reference image(s). Specified up to 14 times.-m, --model: Model selection (nano-banana-2-lite, nano-banana-2, nano-banana-pro, nano-banana). Default: nano-banana-pro.-r, --resolution: Output resolution (1K, 2K, 4K). Default: 1K.--project: GCP Project ID for Vertex AI (optional).--location: GCP Location for Vertex AI (optional, default: us-central1).
Examples
uv run {baseDir}/scripts/banana.py -p "A minimalist tech workspace with a laptop and coffee cup" -f "workspace_lite.png" -m "nano-banana-2-lite"
uv run {baseDir}/scripts/banana.py -p "A photorealistic macro shot of a Monarch butterfly on a flower" -f "butterfly_4k.png" -m "nano-banana-2" -r "4K"
uv run {baseDir}/scripts/banana.py -p "Anime Dani presenting a tech keynote speech" -f "dani_keynote.png" -i "{baseDir}/references/speaker-dani.png" -i "{baseDir}/references/celebrating-dani.png" -m "nano-banana-pro"
uv run {baseDir}/scripts/banana.py -p "banana this photo into chibi style" -i "photo.png" -i "{baseDir}/references/chibi-dani.png" -f "chibi_output.png" -m "nano-banana-2"
