OpenRouter Image Generation MCP Server

An MCP (Model Context Protocol) server that provides image generation capabilities through the OpenRouter API, supporting models like Gemini 2.5 Flash Image Preview.

Features

• Image Generation: Generate images using Google Gemini 2.5 Flash Image Preview

• Flexible Options:

  • Save generated images to local files

Related MCP server: gemini-image-mcp

Installation

1. Clone the repository:

git clone https://github.com/a13.team/openrouter-image-gen-mcp.git
cd openrouter-image-gen-mcp

2. Install dependencies:

npm install

3. Build the TypeScript code:

npm run build

4. Set up your OpenRouter API key:

export OPENROUTER_API_KEY="your-api-key-here"

You can get an API key from OpenRouter.

Configuration for Claude Desktop

Add the following to your Claude Desktop configuration file:

macOS/Linux

Location: ~/.config/claude/claude_desktop_config.json

Windows

Location: %APPDATA%\Claude\claude_desktop_config.json

Cursor IDE Configuration

Location: ./cursor/mcp.json

{
  "mcpServers": {
    "openrouter-image-gen": {
      "command": "node",
      "args": ["/path/to/openrouter-image-gen-mcp/dist/index.js"],
      "env": {
        "OPENROUTER_API_KEY": "your-api-key-here"
      }
    }
  }
}

Replace /path/to/openrouter-image-gen-mcp with the actual path to your installation directory.

Available Tools

1. generate_image

Generate images using AI models.

Parameters:

• prompt (required): Text description of the image to generate

• model: Model to use (default: google/gemini-2.5-flash-image-preview)

• n: Number of images to generate (1-4, default: 1)

• size: Image dimensions (default: 1024x1024)

• save_to_file: Save images locally (default: false)

• filename: Base filename for saved images

• show_full_response: Include full base64 data in response (default: false, returns concise info only)

Example:

{
  "prompt": "A serene Japanese garden with cherry blossoms",
  "model": "google/gemini-2.5-flash-image-preview",
  "save_to_file": true,
  "filename": "japanese_garden"
}

Note: Gemini image generation works through the chat completions API. The model will generate an image based on your prompt and return it as a URL or base64 data in the response. The size parameter is not used for Gemini models.

2. list_models

List all available image generation models.

Development

Build

npm run build

Run in development mode

npm run dev

Start the server

npm start

API Documentation

• Gemini Image Generation

• OpenRouter API

• Model Context Protocol

Troubleshooting

401 Authentication Error

If you get a 401 error, check:

1. Your API key is correctly set in the environment or Claude Desktop config

2. The API key starts with sk-or- (OpenRouter format)

3. The API key is valid and has not expired

4. You have credits available in your OpenRouter account

Test your API key loading:

node test-api-key.js

Common Issues

• API Key not loading: Make sure the OPENROUTER_API_KEY is set in your Claude Desktop config's env section

• Model access denied: Some models require specific permissions or higher tier accounts

• Image not generating for Gemini: Gemini uses the chat completions endpoint, not the images endpoint

License

WTFPL - Do What The Fuck You Want To Public License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Else Models:

`google/gemini-3-pro-image-preview`
`google/gemini-2.5-flash-image`
`google/gemini-2.5-flash-image-preview`