Generate Image
Generate and edit high-quality images using OpenRouter's image generation models including FLUX.2 Pro and Gemini 3 Pro.
When to Use This Skill
Use generate-image for:
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Photos and photorealistic images
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Artistic illustrations and artwork
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Concept art and visual concepts
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Visual assets for presentations or documents
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Image editing and modifications
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Any general-purpose image generation needs
Use scientific-schematics instead for:
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Flowcharts and process diagrams
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Circuit diagrams and electrical schematics
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Biological pathways and signaling cascades
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System architecture diagrams
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CONSORT diagrams and methodology flowcharts
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Any technical/schematic diagrams
Quick Start
Use the scripts/generate_image.py script to generate or edit images:
Generate a new image
python scripts/generate_image.py "A beautiful sunset over mountains"
Edit an existing image
python scripts/generate_image.py "Make the sky purple" --input photo.jpg
This generates/edits an image and saves it as generated_image.png in the current directory.
API Key Setup
CRITICAL: The script requires an OpenRouter API key. Before running, check if the user has configured their API key:
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Look for a .env file in the project directory or parent directories
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Check for OPENROUTER_API_KEY=<key> in the .env file
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If not found, inform the user they need to:
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Create a .env file with OPENROUTER_API_KEY=your-api-key-here
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Or set the environment variable: export OPENROUTER_API_KEY=your-api-key-here
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Get an API key from: https://openrouter.ai/keys
The script will automatically detect the .env file and provide clear error messages if the API key is missing.
Model Selection
Default model: google/gemini-3-pro-image-preview (high quality, recommended)
Available models for generation and editing:
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google/gemini-3-pro-image-preview
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High quality, supports generation + editing
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black-forest-labs/flux.2-pro
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Fast, high quality, supports generation + editing
Generation only:
- black-forest-labs/flux.2-flex
- Fast and cheap, but not as high quality as pro
Select based on:
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Quality: Use gemini-3-pro or flux.2-pro
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Editing: Use gemini-3-pro or flux.2-pro (both support image editing)
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Cost: Use flux.2-flex for generation only
Common Usage Patterns
Basic generation
python scripts/generate_image.py "Your prompt here"
Specify model
python scripts/generate_image.py "A cat in space" --model "black-forest-labs/flux.2-pro"
Custom output path
python scripts/generate_image.py "Abstract art" --output artwork.png
Edit an existing image
python scripts/generate_image.py "Make the background blue" --input photo.jpg
Edit with a specific model
python scripts/generate_image.py "Add sunglasses to the person" --input portrait.png --model "black-forest-labs/flux.2-pro"
Edit with custom output
python scripts/generate_image.py "Remove the text from the image" --input screenshot.png --output cleaned.png
Multiple images
Run the script multiple times with different prompts or output paths:
python scripts/generate_image.py "Image 1 description" --output image1.png python scripts/generate_image.py "Image 2 description" --output image2.png
Script Parameters
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prompt (required): Text description of the image to generate, or editing instructions
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--input or -i : Input image path for editing (enables edit mode)
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--model or -m : OpenRouter model ID (default: google/gemini-3-pro-image-preview)
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--output or -o : Output file path (default: generated_image.png)
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--api-key : OpenRouter API key (overrides .env file)
Example Use Cases
For Scientific Documents
Generate a conceptual illustration for a paper
python scripts/generate_image.py "Microscopic view of cancer cells being attacked by immunotherapy agents, scientific illustration style" --output figures/immunotherapy_concept.png
Create a visual for a presentation
python scripts/generate_image.py "DNA double helix structure with highlighted mutation site, modern scientific visualization" --output slides/dna_mutation.png
For Presentations and Posters
Title slide background
python scripts/generate_image.py "Abstract blue and white background with subtle molecular patterns, professional presentation style" --output slides/background.png
Poster hero image
python scripts/generate_image.py "Laboratory setting with modern equipment, photorealistic, well-lit" --output poster/hero.png
For General Visual Content
Website or documentation images
python scripts/generate_image.py "Professional team collaboration around a digital whiteboard, modern office" --output docs/team_collaboration.png
Marketing materials
python scripts/generate_image.py "Futuristic AI brain concept with glowing neural networks" --output marketing/ai_concept.png
Error Handling
The script provides clear error messages for:
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Missing API key (with setup instructions)
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API errors (with status codes)
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Unexpected response formats
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Missing dependencies (requests library)
If the script fails, read the error message and address the issue before retrying.
Notes
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Images are returned as base64-encoded data URLs and automatically saved as PNG files
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The script supports both images and content response formats from different OpenRouter models
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Generation time varies by model (typically 5-30 seconds)
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For image editing, the input image is encoded as base64 and sent to the model
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Supported input image formats: PNG, JPEG, GIF, WebP
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Check OpenRouter pricing for cost information: https://openrouter.ai/models
Image Editing Tips
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Be specific about what changes you want (e.g., "change the sky to sunset colors" vs "edit the sky")
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Reference specific elements in the image when possible
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For best results, use clear and detailed editing instructions
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Both Gemini 3 Pro and FLUX.2 Pro support image editing through OpenRouter
Integration with Other Skills
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scientific-schematics: Use for technical diagrams, flowcharts, circuits, pathways
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generate-image: Use for photos, illustrations, artwork, visual concepts
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scientific-slides: Combine with generate-image for visually rich presentations
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latex-posters: Use generate-image for poster visuals and hero images