Gemini CLI MCP Server

🇯🇵 日本語

A simple MCP server wrapper for Google's Gemini CLI that enables AI assistants to use Gemini's capabilities through the Model Context Protocol.

✨ Features

• 4 Tools: googleSearch, chat, listSessions, analyzeFile
• Session Persistence: Resume previous conversations with session IDs (supports custom IDs)
• Internationalization: English and Japanese support
• Cross-Platform: Windows, macOS, and Linux compatible

🚀 Quick Setup

With Claude Code

claude mcp add -s project gemini-cli -- npx gemini-cli-mcp-server --allow-npx

Manual Configuration

{
  "mcpServers": {
    "gemini-cli-mcp-server": {
      "command": "npx",
      "args": ["gemini-cli-mcp-server", "--allow-npx"]
    }
  }
}

🛠️ Available Tools

googleSearch

Performs a Google search using Gemini CLI.

Parameter	Required	Description
query	✅	The search query
limit		Maximum number of results
raw		Return structured results with URLs
model		Gemini model (default: gemini-2.5-pro)

chat

Have a conversation with Gemini.

Parameter	Required	Description
prompt	✅	The conversation prompt
sessionId		Resume a previous session (supports custom IDs like "my-task")
model		Gemini model (default: gemini-2.5-pro)

listSessions

Lists available Gemini CLI sessions. Returns session IDs that can be used with chat's sessionId parameter.

analyzeFile

Analyze files using Gemini's multimodal capabilities.

Parameter	Required	Description
filePath	✅	Absolute path to the file
prompt		Additional analysis instructions
sessionId		Resume a previous session (maintains context)
model		Gemini model (default: gemini-2.5-pro)

Supported file types:

• Images: PNG, JPG, JPEG, GIF, WEBP, SVG, BMP
• Text: TXT, MD
• Documents: PDF

💾 Session Management

You can use Custom Session IDs (Client IDs) to manage conversations. The server automatically maps these to Gemini CLI's internal session IDs.

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "chat",
    "arguments": {
      "prompt": "Hello!",
      "sessionId": "my-task-1"
    }
  },
  "id": 1
}

• Persistence: Mappings are stored in memory. They will be reset if the MCP server restarts (Gemini's internal history remains, but the link to your custom ID is lost).
• Listing: Use listSessions to see active mappings.

🌐 Language Settings

Tool descriptions and error messages support multiple languages:

# Japanese
MCP_LANGUAGE=ja npx gemini-cli-mcp-server --allow-npx

# English (default)
MCP_LANGUAGE=en npx gemini-cli-mcp-server --allow-npx

System locale (e.g., LANG=ja_JP.UTF-8) is also auto-detected.

📝 Development

# Clone and install
git clone https://github.com/Cinnamobot/gemini-cli-mcp-server
cd gemini-cli-mcp-server
bun install

# Run tests
bun test

# Build
bun run build

🙏 Credits

This project is based on choplin/mcp-gemini-cli.

Additions from fork

• listSessions tool: List available Gemini CLI sessions
• Session persistence: Resume conversations with sessionId parameter
• Internationalization: Japanese/English support
• Windows compatibility: Custom findExecutable function (no which/where dependency)
• CI/CD: GitHub Actions for automated testing and building

📄 License

MIT License - see LICENSE file for details.

🔗 Related Links

• Model Context Protocol (MCP)
• Gemini CLI