fal-nano-banana-2-image-gen

Required inputs

• --prompt "..." (required)
• workers.jsonc with fal.key (required)

Optional inputs

• Output sizes / aspect ratios:
  • --image-size <preset> (repeatable) or --sizes a,b,c (comma-separated presets)
  • --size <WxH> (repeatable pixel-size hint; sent as { width, height } when supported)
• --negative-prompt, --seed, --num-images, and other model parameters:
  • --param key=value (repeatable; supports dot-paths for nesting)
  • --body-json path/to/body.json (merge arbitrary JSON into the request body)

Workflow

1. Prepare inputs

• Write a prompt that is specific and testable:
  • Subject: what the image is of.
  • Composition: angle, crop, framing, background.
  • Lighting + color: time of day, soft/hard light, mood.
  • Style: photoreal, studio product shot, cinematic, etc.
• If you need to avoid certain elements (logos, text, hands, extra objects), use --negative-prompt.

2. Run

• Use the bundled script to call fal.ai.
• Final deliverables go to artifacts/; request/response logs and intermediate files stay in logs/.
  • Basic:
    • node skills/car-ads-designer/fal-nano-banana-2-image-gen/scripts/generate.mjs --prompt "..." --image-size square_hd
  • Multiple sizes (one call, multiple requests):
    • node skills/car-ads-designer/fal-nano-banana-2-image-gen/scripts/generate.mjs --prompt "..." --image-size square_hd --image-size landscape_16_9
  • Pass extra model parameters (from the model's llms.txt / docs):
    • node skills/car-ads-designer/fal-nano-banana-2-image-gen/scripts/generate.mjs --prompt "..." --param guidance_scale=4.5 --param steps=30

3. Stop and request review (required when subjective/high impact)

• After generation completes, do not take any further actions (no auto-retouching, no upscaling, no additional variants) until a human or designated reviewer confirms the outputs are acceptable.

4. Review outputs

• Inspect the final images under artifacts/... first.
• If something looks off, use the working folder in logs/... to debug (it includes request/response payloads).

Outputs

• Working folder under logs/fal-nano-banana-2-image-gen/<run-id>/ containing inputs and full request/response logs.
• Final folder under artifacts/fal-nano-banana-2-image-gen/<run-id>/ containing:
  • README.md (what was generated + where the working logs are)
  • One or more final images (and per-size subfolders when multiple sizes are requested)

Definition of done

• The script completes without errors and writes at least one image file under artifacts/.
• The output matches the prompt intent.
• A human (or designated agent reviewer) has reviewed the outputs and explicitly approved any next steps.

Safety / quality checklist

• Do not commit secrets.
• Do not paste/print keys from workers.jsonc; only confirm whether values are present.
• Avoid generating copyrighted logos/marks you don’t have rights to use.
• Treat rendered text as unreliable; avoid high-stakes text (prices, legal claims) unless you will manually verify/correct.
• Don’t include sensitive personal data in prompts unless you have permission and a clear need.