| name | image-gen |
| description | Generate images using FAL (Flux Pro 1.1 Ultra), Gemini (nano-banana 2), or OpenAI. Supports generation, editing, and refinement workflows. Use for any image creation task. |
Image Generation Skill
Multi-provider image generation with a preference hierarchy:
- FAL Flux Pro 1.1 Ultra — Primary generator (best quality, 9:16 native)
- Gemini nano-banana 2 — Editing/refinement (fix hands, details, consistency)
- OpenAI DALL-E 3 — Fallback generator
Prerequisites
| Provider | Env Var | Status |
|---|
| FAL | FAL_KEY | Required for Flux |
| Gemini | GEMINI_API_KEY | Required for editing |
| OpenAI | OPENAI_API_KEY | Optional fallback |
Quick Usage
Generate with Flux (9:16 portrait)
node skills/image-gen/scripts/fal-generate.js \
--prompt "A solarpunk garden city at golden hour" \
--aspect "9:16" \
--output ./images/garden.png
Edit with Gemini (nano-banana)
node skills/image-gen/scripts/gemini-edit.js \
--image ./images/garden.png \
--instruction "Fix the hands to have exactly 5 fingers" \
--output ./images/garden-fixed.png
Full Pipeline (generate → refine)
node skills/image-gen/scripts/pipeline.js \
--prompt "A solarpunk garden city at golden hour" \
--aspect "9:16" \
--refine "Ensure all human figures have correct anatomy" \
--output ./images/final.png
Workflow: Lofn Image Pipeline
- Concept Phase (skills/image/00-03): Generate aesthetics, concepts, artist/critique
- Prompt Synthesis (skills/image/04-10): Build final prompt
- Generation (this skill): FAL Flux Pro 1.1 Ultra @ 9:16
- Refinement (this skill): Gemini nano-banana for fixes
- Output: Final image saved to workspace
FAL Flux Pro 1.1 Ultra
Endpoint: fal-ai/flux-pro/v1.1-ultra
Key Parameters:
prompt: The generation prompt
aspect_ratio: 21:9, 16:9, 4:3, 3:2, 1:1, 2:3, 3:4, 9:16, 9:21
output_format: jpeg, png
safety_tolerance: 1 (strict) to 6 (permissive)
raw: true for less processed, natural look
seed: for reproducibility
Cost: ~$0.06 per image
Gemini nano-banana 2 (Image Editing)
Uses Gemini's native image generation/editing capabilities.
Models:
gemini-2.0-flash-exp — Fast editing
gemini-2.0-pro — Higher quality edits
Use Cases:
- Fix anatomical issues (hands, fingers, faces)
- Adjust clothing/accessories
- Color correction
- Add/remove elements
- Style transfer
Error Handling
- FAL timeout: Retry with exponential backoff (max 3 attempts)
- NSFW block: Adjust
safety_tolerance or rephrase prompt
- Gemini edit fail: Fallback to regeneration with refined prompt
Output Structure
All generated images saved with metadata:
images/
{timestamp}_{seed}.png
{timestamp}_{seed}.json # metadata: prompt, params, provider
Integration with Lofn Pipeline
This skill is called by skills/image/08_Generate_Image_Generation.md after prompt synthesis completes. It can also be invoked directly for quick generations.