Generate Image

Generate images using Gemini 3 Pro image generation (gemini-3-pro-image-preview).

When to Use

Use this skill when the user asks to:

• Generate an image from a text prompt
• Create artwork, illustrations, or graphics
• Generate variations of an existing image (img2img)
• Create scenes with multiple reference images (character + location + other characters)

Gather Design Direction First

Ask clarifying questions before rewriting prompts to understand the user’s intent:

1. Purpose: What is the image for? (banner, logo, social media, product shot, art piece)
2. Style preference: Photorealistic, illustrated, minimalist, abstract, specific art style?
3. Color palette: Any brand colors? Dark/light theme? Specific mood?
4. Composition constraints: Aspect ratio needs? Text overlay space? Full-bleed vs bordered?
5. Key elements: What must be included? What should be avoided?

Simple requests like “make a cat image” can proceed with sensible defaults. Complex requests like “create a banner for my app” require clarification to avoid iteration waste.

Prompt Rewriting (Critical)

Before generating any image, always rewrite the user’s prompt using the guide in references/prompt-guide.md.

The core principle: “Describe the scene, don’t just list keywords.”

Rewriting Checklist

Transform simple prompts by adding:

1. Subject details: Specific appearance, clothing, expression, materials
2. Environment/Setting: Location, time of day, weather, indoor/outdoor
3. Lighting: Natural/artificial, direction, quality, color temperature
4. Composition: Camera angle, distance, framing, focal length
5. Style/Aesthetic: Photorealistic, illustration style, art movement
6. Mood/Atmosphere: Emotional tone, color palette mood
7. Technical specs: Aspect ratio, level of detail, textures

Example Transformation

User says: “banner for my app” Rewritten prompt: “A modern, full-bleed banner for a technology application. Dark gradient background transitioning from deep navy to black. Abstract geometric network visualization with glowing nodes connected by thin lines. Clean sans-serif typography positioned left of center. Professional, tech-forward aesthetic with no visible borders or edges – the design extends seamlessly to all edges. 16:9 aspect ratio.”

User says: “a cat” Rewritten prompt: “A fluffy orange tabby cat lounging on a sun-drenched windowsill, soft afternoon light creating a warm glow on its fur. The cat is in a relaxed pose with half-closed eyes, conveying contentment. Shot from a low angle with shallow depth of field, the background showing a blurred garden view. Photorealistic, warm color palette.”

Recommended Workflow

Draft → Iterate → Final approach saves time and API costs:

1. Draft Phase (1K): Generate quickly at default resolution to test prompts
2. Iteration Phase: Refine prompts incrementally, creating new files each attempt
3. Final Phase (4K): Only produce high-res output after prompt is validated

Do not read the image back – the script outputs only the file path. This allows efficient iteration without Claude loading large image data.

Usage

cd ${CLAUDE_PLUGIN_ROOT}/skills/generate-image && bun run scripts/generate.ts "prompt" [options]

Options

• --input <path> – Reference image (can specify multiple times, up to 14 images)
• --style <id> – Apply style from the style library (see browsing-styles skill)
• --size <1K|2K|4K> – Image size (default: 1K for fast drafts)
• --aspect <ratio> – Aspect ratio: 1:1, 16:9, 9:16, 4:3, 3:4
• --negative <prompt> – Negative prompt (what to avoid)
• --count <n> – Number of images (1-4, default: 1)
• --guidance <n> – Guidance scale
• --seed <n> – Random seed for reproducibility
• --output <path> – Output path

Examples

# Simple generation
bun run scripts/generate.ts "cyberpunk cityscape at night"

# With art style (100+ available, use short names or full IDs)
bun run scripts/generate.ts "mountain landscape" --style impressionism
bun run scripts/generate.ts "portrait" --style ukiy
bun run scripts/generate.ts "city street" --style noir

# High-res with specific aspect ratio
bun run scripts/generate.ts "mountain landscape" --size 4K --aspect 16:9

# With negative prompt
bun run scripts/generate.ts "portrait of a cat" --negative "low quality, blurry"

# Combine style with other options
bun run scripts/generate.ts "cat sleeping" --style wtrc --size 4K --aspect 1:1

# Generate multiple variations
bun run scripts/generate.ts "abstract art" --count 4

# Single reference image (img2img)
bun run scripts/generate.ts "make it look like a watercolor painting" --input photo.jpg

# Multiple reference images (character consistency, scene composition)
bun run scripts/generate.ts "King on throne in dramatic lighting" \
  --input character.png \
  --input throne-room.png \
  --aspect 16:9 --size 2K

# Multiple characters in a scene
bun run scripts/generate.ts "Two warriors facing each other in combat" \
  --input warrior1.png \
  --input warrior2.png \
  --input battlefield.png \
  --aspect 16:9

Multiple Reference Images

Gemini supports up to 14 reference images per request:

• 6 objects – Locations, items, environments
• 5 humans – Character consistency across generations
• Use detailed prompts describing how reference images should be combined
• Reference images help maintain consistency across scene generations

Available Styles

Use the browsing-styles skill to browse all 100+ styles:

• bun run ../browsing-styles/scripts/preview_server.ts – Interactive browser
• bun run ../browsing-styles/scripts/list_styles.ts --table – CLI list

Popular styles: impr (Impressionism), ukiy (Ukiyo-e), cybr (Cyberpunk), pixl (Pixel Art), noir (Film Noir), anim (Anime), wtrc (Watercolor)

Model

Uses gemini-3-pro-image-preview (Gemini 3 Pro) for image generation.

Reference Files

For detailed prompting strategies and techniques:

• references/prompt-guide.md – Comprehensive Gemini prompting guide with 7 strategies, example transformations, and best practices from Google’s official documentation