Image Generation CLI (Nano Banana 2 + GPT Image 2)

Generate or edit images via {baseDir}/scripts/generate.py. Choose the backend with --provider:

--provider	Model	Best For
gemini (default)	Nano Banana 2 (Gemini 3.1 Flash)	Multi-aspect-ratio output, 512px–4K, fast iterations
gpt	gpt-image-2 (OpenAI)	High-fidelity photorealism, precise text rendering

Usage

# Text-to-image (Gemini, default)
python {baseDir}/scripts/generate.py --prompt "A mountain landscape at dawn" --aspect-ratio 16:9 --output landscape.png

# Text-to-image (GPT Image 2)
python {baseDir}/scripts/generate.py --prompt "A poster with bold serif text" --provider gpt --quality high --output poster.png

# Image-to-image (edit or composite)
python {baseDir}/scripts/generate.py --prompt "Place this photo in a card layout" --input photo.jpg --output card.png

# Image-to-image with GPT
python {baseDir}/scripts/generate.py --prompt "Replace the sky with aurora" --input photo.jpg --provider gpt --output edited.png

When the user provides a real-world photograph, preserve it as a photograph — do not redraw, stylize, or convert to illustration unless the user explicitly requests it.

Parameters

Flag	Default	Description
--prompt, -p	(required)	Text prompt or editing instructions
--output, -o	(required)	Output image path
--input, -i	—	Input image path (triggers image-to-image)
--provider	gemini	gemini or gpt
--aspect-ratio, -a	1:1	[gemini] Aspect ratio: 1:1, 16:9, 9:16, 4:3, 3:4, 21:9, etc.
--size, -s	—	[gemini] Output size: 512, 1K, 2K, 4K
--quality, -q	—	[gpt] Render quality: low, medium, high, auto
--image-size	—	[gpt] Pixel dimensions: 1024x1024, 1024x1536, 1536x1024, auto
--format, -f	—	[gpt] Output format: png, webp, jpeg
--background	—	[gpt] opaque or auto
--moderation	—	[gpt] auto or low (less restrictive)

Cost Guide

Call	Credits (1 credit = $0.01)
gemini (any)	10 ($0.10)
gpt, quality: low	10 ($0.10)
gpt, quality: medium/auto	15 ($0.15)
gpt, quality: high	25 ($0.25)

Default to Gemini for most needs. Only use --provider gpt when the user specifically needs photorealism or precise text rendering. Only use --quality high for final deliverables, not drafts.

Error Handling

The script exits with code 1 and prints errors to stderr on failure:

• Auth error: Ensure ~/.rebyte.ai/auth.json exists with valid credentials
• Safety filter: Prompt was blocked — rephrase and retry
• No image: API returned no image data — simplify the prompt

Delivering Output

After generating images, upload them to the Artifact Store so the user can access them.