image-generation

Installation
Summary

Generate high-quality images via Gemini models with structured prompts, aspect ratios, and brand validation.

  • Supports three Gemini models (gemini-3-pro-image, gemini-2.5-flash-image, gemini-2.5-pro-image) optimized for different quality-speed tradeoffs
  • Enforces structured prompt format covering subject, style, lighting, mood, composition, aspect ratio, and brand colors to ensure consistency
  • Includes multi-agent workflow for prompt validation, style verification, and output delivery across Claude, Gemini, and Codex
  • Generates 2-4 variants per request with metadata tracking (prompt, model, ratio, timestamp) for reproducibility and brand alignment
SKILL.md

Image Generation via MCP

AI image generation skill via MCP. Use Gemini models or compatible services to generate high-quality images for marketing, UI, and presentations.

When to use this skill

  • Marketing assets: Hero images, banners, social media content
  • UI/UX design: Placeholder images, icons, illustrations
  • Presentations: Slide backgrounds, product visualizations
  • Brand consistency: Generate images based on a style guide

Instructions

Step 1: Configure MCP Environment

# Check MCP server configuration
claude mcp list

# Check Gemini CLI availability
# gemini-cli must be installed

Required setup:

  • Model name (gemini-2.5-flash, gemini-3-pro, etc.)
  • API key reference (stored as an environment variable)
  • Output directory

Step 2: Define the Prompt

Write a structured prompt:

**Subject**: [main subject]
**Style**: [style - minimal, illustration, photoreal, 3D, etc.]
**Lighting**: [lighting - natural, studio, golden hour, etc.]
**Mood**: [mood - calm, dynamic, professional, etc.]
**Composition**: [composition - centered, rule of thirds, etc.]
**Aspect Ratio**: [ratio - 16:9, 1:1, 9:16]
**Brand Colors**: [brand color constraints]

Step 3: Choose the Model

Model Use case Notes
gemini-3-pro-image High quality Complex compositions, detail
gemini-2.5-flash-image Fast iteration Prototyping, testing
gemini-2.5-pro-image Balanced Quality/speed balance

Step 4: Generate and Review

# Generate 2-4 variants
ask-gemini "Create a serene mountain landscape at sunset,
  wide 16:9, minimal style, soft gradients in brand blue #2563EB"

# Iterate by changing a single variable
ask-gemini "Same prompt but with warm orange tones"

Review checklist:

  • Brand fit
  • Composition clarity
  • Ratio correctness
  • Text readability (if text is included)

Step 5: Deliverables

Final deliverables:

  • Final image files
  • Prompt metadata record
  • Model, ratio, usage notes
{
  "prompt": "serene mountain landscape at sunset...",
  "model": "gemini-3-pro-image",
  "aspect_ratio": "16:9",
  "style": "minimal",
  "brand_colors": ["#2563EB"],
  "output_file": "hero-image-v1.png",
  "timestamp": "2026-01-21T10:30:00Z"
}

Examples

Example 1: Hero Image

Prompt:

Create a serene mountain landscape at sunset,
wide 16:9, minimal style, soft gradients in brand blue #2563EB.
Focus on clean lines and modern aesthetic.

Expected output:

  • 16:9 hero image
  • Prompt parameters saved
  • 2-3 variants for selection

Example 2: Product Thumbnail

Prompt:

Generate a 1:1 thumbnail of a futuristic dashboard UI
with clean interface, soft lighting, and professional feel.
Include subtle glow effects and dark theme.

Expected output:

  • 1:1 square image
  • Low visual noise
  • App store ready

Example 3: Social Media Banner

Prompt:

Create a LinkedIn banner (1584x396) for a SaaS startup.
Modern gradient background with abstract geometric shapes.
Colors: #6366F1 to #8B5CF6.
Leave space for text overlay on the left side.

Expected output:

  • LinkedIn-optimized dimensions
  • Safe zone for text
  • Brand-aligned colors

Best practices

  1. Specify ratio early: Prevent unintended crops
  2. Use style anchors: Maintain consistent aesthetics
  3. Iterate with constraints: Change only one variable at a time
  4. Track prompts: Ensure reproducibility
  5. Batch similar requests: Create a consistent style set

Common pitfalls

  • Vague prompts: Specify concrete style and composition
  • Ignoring size constraints: Check target channel dimension requirements
  • Overly complex scenes: Simplify for clarity

Troubleshooting

Issue: Outputs are inconsistent

Cause: Missing stable style constraints Solution: Add style references and a fixed palette

Issue: Wrong aspect ratio

Cause: Ratio not specified or an unsupported ratio Solution: Provide an exact ratio and regenerate

Issue: Brand mismatch

Cause: Color codes not specified Solution: Specify brand colors via HEX codes


Output format

## Image Generation Report

### Request
- **Prompt**: [full prompt]
- **Model**: [model used]
- **Ratio**: [aspect ratio]

### Output Files
1. `filename-v1.png` - [description]
2. `filename-v2.png` - [variant description]

### Metadata
- Generated: [timestamp]
- Iterations: [count]
- Selected: [final choice]

### Usage Notes
[Any notes for implementation]

Multi-Agent Workflow

Validation & Retrospectives

  • Round 1 (Orchestrator): Prompt completeness, ratio correctness
  • Round 2 (Analyst): Style consistency, brand alignment
  • Round 3 (Executor): Validate output filenames, delivery checklist

Agent Roles

Agent Role
Claude Prompt structuring, quality verification
Gemini Run image generation
Codex File management, batch processing

Metadata

Version

  • Current Version: 1.0.0
  • Last Updated: 2026-01-21
  • Compatible Platforms: Claude, ChatGPT, Gemini, Codex

Related Skills

Tags

#image-generation #gemini #mcp #design #creative #ai-art

Weekly Installs
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GitHub Stars
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First Seen
Mar 6, 2026