Nano Banana MCP

MCP Server for image generation using Gemini Web API (reverse-engineered).

⚠️ Disclaimer: This project uses unofficial API access via browser cookies. Use at your own risk.

Features

• 🎨 Text-to-Image Generation: Create images from text prompts
• ✏️ Image Editing: Modify existing images with natural language
• 💬 Chat: Interact with Gemini for text and image generation
• 🎯 App Icon Generation: Generate professional app icons with:
  • Automatic background removal (rembg/RMBG 2.0)
  • Platform presets (iOS, Android, macOS, Web)
  • Multiple sizes generation
  • Shape masks (squircle, rounded, circle)
• 🔲 Pattern Generation: Create seamless patterns and textures
• 📊 Diagram Generation: Generate technical diagrams and flowcharts
• 🖼️ Banner/Thumbnail Generation: Social media and YouTube ready

Architecture

┌─────────────────┐     MCP Protocol     ┌──────────────────┐
│   AI Client     │◄───────────────────►│  nano-banana-mcp │
│ (Claude, etc.)  │                      │     (Python)     │
└─────────────────┘                      └────────┬─────────┘
                                                  │
                                                  │ gemini_webapi
                                                  ▼
                                         ┌──────────────────┐
                                         │  Gemini Web UI   │
                                         │  (Google Server) │
                                         └──────────────────┘

Prerequisites

• Python 3.10+
• Google account with Gemini access
• Browser cookies from gemini.google.com

Installation

# Clone the repository
git clone <your-repo-url>
cd nano-banana-mcp

# Install with pip (basic)
pip install -e .

# Or with uv
uv pip install -e .

Optional Dependencies

Background Removal (for App Icons)

Choose one of the following options:

# Option 1: rembg (Recommended - lightweight, CPU-only)
pip install rembg[cpu]

# Option 2: rembg with GPU acceleration
pip install rembg[gpu]

# Option 3: RMBG 2.0 (Best quality - requires more resources)
pip install transformers torch torchvision

Background Removal Engines Comparison:

Engine	Quality	Speed	Size	GPU Required
rmbg2 (BRIA RMBG 2.0)	Best (90%)	Medium	~500MB	Optional (faster with CUDA)
rembg + isnet-general-use	Excellent	Medium	170MB	No
rembg + isnet-anime	Excellent	Medium	170MB	No (best for icons)
rembg + silueta	Good	Fastest	43MB	No
rembg + u2netp	Good	Fast	4.7MB	No

Environment Variables for Background Removal:

# Choose engine: 'rembg' (default) or 'rmbg2' (best quality)
BG_REMOVAL_ENGINE=rembg

# Choose rembg model (if using rembg engine)
REMBG_MODEL=isnet-general-use  # Options: u2netp, isnet-general-use, isnet-anime, silueta, birefnet-general

Configuration

1. Get Your Cookies (Important!)

⚠️ Cookie Expiration: The __Secure-1PSIDTS cookie expires frequently (sometimes in minutes). Follow these community-tested tips to maximize cookie lifespan:

Best Practices for Long-Lasting Cookies:

1. Use Incognito Mode (Highly Recommended)

   • Open an incognito/private browser window
   • Log in to gemini.google.com
   • Get your cookies from there
   • Cookies obtained in incognito can last weeks/months

2. Close Gemini Immediately After Getting Cookies

   • After copying cookies, close the Gemini tab immediately
   • Keeping Gemini open in browser causes cookies to expire faster
   • Don't visit gemini.google.com while using this tool

3. Use a Dedicated Google Account

   • Cookies expire faster when the account is used actively elsewhere
   • Consider creating a separate account just for API access

4. When Cookies Expire

   • Usually only __Secure-1PSIDTS expires first
   • Try updating just PSIDTS using the set_cookie tool
   • If that fails, get fresh __Secure-1PSID as well

Steps to Get Cookies:

1. Open Incognito window (Ctrl+Shift+N / Cmd+Shift+N)
2. Go to gemini.google.com and log in
3. Open DevTools (F12) → Application → Cookies
4. Copy the value of __Secure-1PSID (required)
5. Copy __Secure-1PSIDTS if available (some accounts don't have it)
6. Close the Gemini tab immediately

2. Set Environment Variables

Create a .env file:

# Required
GEMINI_SECURE_1PSID=your_cookie_value_here

# Optional
GEMINI_SECURE_1PSIDTS=your_cookie_value_here
NANOBANANA_OUTPUT_DIR=./nanobanana-output
NANOBANANA_MODEL=gemini-2.0-flash-exp
NANOBANANA_TIMEOUT=60

3. Configure MCP Client

Add to your MCP client config (e.g., Claude Desktop):

{
  "mcpServers": {
    "nano-banana": {
      "command": "nano-banana-mcp",
      "env": {
        "GEMINI_SECURE_1PSID": "your_cookie_value"
      }
    }
  }
}

Or with Python directly:

{
  "mcpServers": {
    "nano-banana": {
      "command": "python",
      "args": ["-m", "nano_banana_mcp.server"],
      "cwd": "/path/to/nano-banana-mcp",
      "env": {
        "GEMINI_SECURE_1PSID": "your_cookie_value"
      }
    }
  }
}

Usage

Generate Image

Generate an image of a sunset over mountains

Edit Image

Edit my_photo.png: add sunglasses to the person

Generate Icon

Create an app icon for a music player app

Advanced icon generation:

Generate app icon for a fitness app with platform=ios, style=gradient, shape=squircle

Available options:

• platform: ios, android, web, macos, all
• style: flat-design, modern, minimalist, 3d-render, isometric, gradient, glassmorphism
• shape: squircle (iOS style), rounded, circle, square
• remove_background: true/false
• background_color: hex color like #FF5733 or named color

Generate Pattern

Create a seamless geometric pattern in blue tones

Generate Diagram

Create a flowchart for user authentication

Available Tools

Tool	Description
generate_image	Generate images from text prompts with style/mood options
edit_image	Edit existing images with natural language
chat	General chat with image support
generate_app_icon	Generate app icons with background removal & platform presets
generate_banner	Generate banners (16:9, 21:9 aspect ratios)
generate_thumbnail	Generate YouTube/video thumbnails
generate_logo	Generate logo designs
generate_pattern	Generate seamless patterns and textures
generate_diagram	Generate technical diagrams and flowcharts
generate_illustration	Generate artistic illustrations
generate_social_post	Generate social media images
generate_product_photo	Generate product photography
set_cookie	Update expired cookies

Output

Generated images are saved to ./nanobanana-output/ by default.

Troubleshooting

"SECURE_1PSIDTS could get expired frequently"

This is the most common error. Solutions in order of priority:

1. Get cookies from incognito mode and close Gemini tab immediately
2. Use set_cookie tool to update just the PSIDTS value
3. Update PSID as well - sometimes PSID itself expires (per community feedback)
4. Use a dedicated Google account that isn't used elsewhere

"Missing GEMINI_SECURE_1PSID"

• Ensure you copied the correct cookie value
• Cookie value should start with g.a...

"Image generation failed"

• Check if your Google account has Gemini access
• Try a simpler prompt
• Cookies may have expired - check the error message

Rate Limiting

• Wait between requests if you encounter errors
• Avoid rapid successive requests

Keep-Alive Feature

This MCP server includes an automatic keep-alive mechanism that helps extend cookie lifespan:

• Sends background pings every 30 minutes
• Automatically refreshes __Secure-1PSIDTS when possible
• Requirement: The MCP server process must stay running continuously

The keep-alive works best with cookies obtained from incognito mode on a dedicated account.

Limitations

• ⚠️ Cookies can expire (use incognito + dedicated account to minimize)
• ⚠️ May be rate-limited by Google
• ⚠️ API can change without notice
• ⚠️ Not suitable for production use

License

MIT

Disclaimer

This project is for educational purposes only. It uses unofficial API access and may violate Google's Terms of Service. Use responsibly and at your own risk.