Nano Banana 2 - Gemini 3.1 Flash Image Preview

Generate images with Google Gemini 3.1 Flash Image Preview via inference.sh CLI.

Quick Start

Requires inference.sh CLI (belt). Install instructions

belt login

belt app run google/gemini-3-1-flash-image-preview --input '{"prompt": "a banana in space, photorealistic"}'

Examples

Basic Text-to-Image

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "A futuristic cityscape at sunset with flying cars"
}'

Multiple Images

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "Minimalist logo design for a coffee shop",
  "num_images": 4
}'

Custom Aspect Ratio

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "Panoramic mountain landscape with northern lights",
  "aspect_ratio": "16:9"
}'

Image Editing (with input images)

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "Add a rainbow in the sky",
  "images": ["https://example.com/landscape.jpg"]
}'

High Resolution (4K)

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "Detailed illustration of a medieval castle",
  "resolution": "4K"
}'

With Google Search Grounding

belt app run google/gemini-3-1-flash-image-preview --input '{
  "prompt": "Current weather in Tokyo visualized as an artistic scene",
  "enable_google_search": true
}'

Input Options

Parameter	Type	Description
prompt	string	Required. What to generate or change
images	array	Input images for editing (up to 14). Supported: JPEG, PNG, WebP
num_images	integer	Number of images to generate
aspect_ratio	string	Output ratio: "1:1", "16:9", "9:16", "4:3", "3:4", "auto"
resolution	string	"1K", "2K", "4K" (default: 1K)
output_format	string	Output format for images
enable_google_search	boolean	Enable real-time info grounding (weather, news, etc.)

Output

Field	Type	Description
images	array	The generated or edited images
description	string	Text description or response from the model
output_meta	object	Metadata about inputs/outputs for pricing

Prompt Tips

Styles: photorealistic, illustration, watercolor, oil painting, digital art, anime, 3D render

Composition: close-up, wide shot, aerial view, macro, portrait, landscape

Lighting: natural light, studio lighting, golden hour, dramatic shadows, neon

Details: add specific details about textures, colors, mood, atmosphere

Sample Workflow

# 1. Generate sample input to see all options
belt app sample google/gemini-3-1-flash-image-preview --save input.json

# 2. Edit the prompt
# 3. Run
belt app run google/gemini-3-1-flash-image-preview --input input.json

Python SDK

from inferencesh import inference

client = inference()

# Basic generation
result = client.run({
    "app": "google/gemini-3-1-flash-image-preview@0c7ma1ex",
    "input": {
        "prompt": "A banana in space, photorealistic"
    }
})
print(result["output"])

# Stream live updates
for update in client.run({
    "app": "google/gemini-3-1-flash-image-preview@0c7ma1ex",
    "input": {
        "prompt": "A futuristic cityscape at sunset"
    }
}, stream=True):
    if update.get("progress"):
        print(f"progress: {update['progress']}%")
    if update.get("output"):
        print(f"output: {update['output']}")

Related Skills

# Original Nano Banana (Gemini 3 Pro Image, Gemini 2.5 Flash Image)
npx skills add inference-sh/skills@nano-banana

# Full platform skill (all 250+ apps)
npx skills add inference-sh/skills@infsh-cli

# All image generation models
npx skills add inference-sh/skills@ai-image-generation

Browse all image apps: belt app list --category image

Documentation

• Running Apps - How to run apps via CLI
• Streaming Results - Real-time progress updates
• File Handling - Working with images