mcp-alphabanana MCP Server

mcp-alphabanana

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mcp-alphabanana is a Model Context Protocol (MCP) server for generating image assets with Google Gemini. It is built for MCP-compatible clients and agent workflows that need fast image generation, transparent outputs, reference-image guidance, and flexible delivery formats.

Keywords: MCP server, Model Context Protocol, Gemini AI, image generation, FastMCP

Key capabilities:

• Ultra-fast Gemini image generation across Flash and Pro tiers
• Transparent PNG/WebP asset output for web and game pipelines
• Multi-image style guidance with local reference image files
• Flexible file, base64, or combined outputs for agent workflows

Quick Start

Run the MCP server with npx:

npx -y @tasopen/mcp-alphabanana

Download the latest MCPB bundle for Claude Desktop or registry ingestion:

https://github.com/tasopen/mcp-alphabanana/releases/latest/download/mcp-alphabanana-latest.mcpb

GitHub Releases is the canonical distribution channel for .mcpb bundles. Each release publishes both a versioned asset and the stable mcp-alphabanana-latest.mcpb filename.

Or add it to your MCP configuration:

{
  "mcp": {
    "servers": {
      "alphabanana": {
        "command": "npx",
        "args": ["-y", "@tasopen/mcp-alphabanana"],
        "env": {
          "GEMINI_API_KEY": "${env:GEMINI_API_KEY}"
        }
      }
    }
  }
}

Set GEMINI_API_KEY before starting the server.

Claude Registry

The Claude registry / MCPB package metadata is defined in manifest.json and ships with the static 512x512 icon at images/mcp-alphabanana.png.

Native sharp runtime packages are declared as optional dependencies so .mcpb installs can resolve the correct prebuilt binary on each supported platform without relying on postinstall hooks.

• Stable MCPB URL: https://github.com/tasopen/mcp-alphabanana/releases/latest/download/mcp-alphabanana-latest.mcpb
• Versioned MCPB URL pattern: https://github.com/tasopen/mcp-alphabanana/releases/download/vVERSION/mcp-alphabanana-VERSION.mcpb
• Support: GitHub Issues

MCP Server

This repository provides an MCP server that enables AI agents to generate images using Google Gemini.

It can be used with MCP-compatible clients such as:

• Claude Desktop
• VS Code MCP
• Cursor

Built with FastMCP 3 for a simplified codebase and flexible output options.

Glama MCP Server badge:
<a href="https://glama.ai/mcp/servers/tasopen/mcp-alphabanana">

Available Tools

generate_image

Generates images using Google Gemini with optional transparency, local reference images, grounding, and reasoning metadata.

For Claude Desktop, prefer outputType=file for medium or large images. base64 and combine responses consume Claude context and can hit the client's size limit. On Windows, use the FileSystem extension to choose a writable absolute outputPath and any local referenceImages paths.

Key parameters:

• prompt (string): description of the image to generate
• model: Flash3.1, Flash2.5, Pro3, flash, pro
• outputWidth and outputHeight: requested final image size in pixels in normal mode
• noresize + aspectRatio + output_resolution: return Gemini native size without resizing
• output_resolution: 0.5K, 1K, 2K, 4K
• output_format: png, jpg, webp
• outputType: file, base64, combine
• outputPath: required when outputType is file or combine
• transparent: enable transparent PNG/WebP post-processing
• referenceImages: optional array of local reference image files
• grounding_type and thinking_mode: advanced Gemini 3.1 controls

Model Selection

Parameters

Full parameter reference for the generate_image tool.