MCP MongoDB Server

A Model Context Protocol server that enables LLMs to interact with MongoDB databases. This server provides capabilities for inspecting collection schemas and executing MongoDB operations through a standardized interface.

Demo

Key Features

Smart ObjectId Handling

• Intelligent conversion between string IDs and MongoDB ObjectId
• Configurable with objectIdMode parameter:
  • "auto": Convert based on field names (default)
  • "none": No conversion
  • "force": Force all string ID fields to ObjectId

Flexible Configuration

• Environment Variables:
  • MCP_MONGODB_URI: MongoDB connection URI
  • MCP_MONGODB_READONLY: Enable read-only mode when set to "true"
• Command-line Options:
  • --read-only or -r: Connect in read-only mode

Read-Only Mode

• Protection against write operations (update, insert, createIndex)
• Uses MongoDB's secondary read preference for optimal performance
• Ideal for safely connecting to production databases

MongoDB Operations

• Read Operations:
  • Query documents with optional execution plan analysis
  • Execute aggregation pipelines
  • Count documents matching criteria
  • Get collection schema information
• Write Operations (when not in read-only mode):
  • Update documents
  • Insert new documents
  • Create indexes

LLM Integration

• Collection completions for enhanced LLM interaction
• Schema inference for improved context understanding
• Collection analysis for data insights

Installation

Global Installation

npm install -g mcp-mongo-server

For Development

# Clone repository
git clone https://github.com/kiliczsh/mcp-mongo-server.git
cd mcp-mongo-server

# Install dependencies
npm install

# Build
npm run build

# Development with auto-rebuild
npm run watch

Usage

Basic Usage

# Start server with MongoDB URI
npx -y mcp-mongo-server mongodb://muhammed:kilic@localhost:27017/database

# Connect in read-only mode
npx -y mcp-mongo-server mongodb://muhammed:kilic@localhost:27017/database --read-only

Environment Variables

You can configure the server using environment variables, which is particularly useful for CI/CD pipelines, Docker containers, or when you don't want to expose connection details in command arguments:

# Set MongoDB connection URI
export MCP_MONGODB_URI="mongodb://muhammed:kilic@localhost:27017/database"

# Enable read-only mode
export MCP_MONGODB_READONLY="true"

# Run server (will use environment variables if no URI is provided)
npx -y mcp-mongo-server

Using environment variables in Claude Desktop configuration:

{
  "mcpServers": {
    "mongodb-env": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server"
      ],
      "env": {
        "MCP_MONGODB_URI": "mongodb://muhammed:kilic@localhost:27017/database",
        "MCP_MONGODB_READONLY": "true"
      }
    }
  }
}

Using environment variables with Docker:

# Build
docker build -t mcp-mongo-server .

# Run
docker run -it -d -e MCP_MONGODB_URI="mongodb://muhammed:kilic@localhost:27017/database" -e MCP_MONGODB_READONLY="true" mcp-mongo-server

# or edit docker-compose.yml and run
docker-compose up -d

Integration with Claude Desktop

Manual Configuration

Add the server configuration to Claude Desktop's config file:

MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%/Claude/claude_desktop_config.json

Command-line Arguments Approach:

{
  "mcpServers": {
    "mongodb": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database"
      ]
    },
    "mongodb-readonly": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database",
        "--read-only"
      ]
    }
  }
}

Environment Variables Approach:

{
  "mcpServers": {
    "mongodb": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server"
      ],
      "env": {
        "MCP_MONGODB_URI": "mongodb://muhammed:kilic@localhost:27017/database"
      }
    },
    "mongodb-readonly": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server"
      ],
      "env": {
        "MCP_MONGODB_URI": "mongodb://muhammed:kilic@localhost:27017/database",
        "MCP_MONGODB_READONLY": "true"
      }
    }
  }
}

GitHub Package Usage:

{
  "mcpServers": {
    "mongodb": {
      "command": "npx",
      "args": [
        "-y",
        "github:kiliczsh/mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database"
      ]
    },
    "mongodb-readonly": {
      "command": "npx",
      "args": [
        "-y",
        "github:kiliczsh/mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database",
        "--read-only"
      ]
    }
  }
}

Integration with Windsurf and Cursor

The MCP MongoDB Server can be used with Windsurf and Cursor in a similar way to Claude Desktop.

Windsurf Configuration

Add the server to your Windsurf configuration:

{
  "mcpServers": {
    "mongodb": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database"
      ]
    }
  }
}

Cursor Configuration

For Cursor, add the server configuration to your settings:

{
  "mcpServers": {
    "mongodb": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mongo-server",
        "mongodb://muhammed:kilic@localhost:27017/database"
      ]
    }
  }
}

You can also use the environment variables approach with both Windsurf and Cursor, following the same pattern shown in the Claude Desktop configuration.

Automated Installation

Using Smithery:

npx -y @smithery/cli install mcp-mongo-server --client claude

Using mcp-get:

npx @michaellatman/mcp-get@latest install mcp-mongo-server

Available Tools

Query Operations

• query: Execute MongoDB queries

  javascriptCopy

  {
    collection: "users",
    filter: { age: { $gt: 30 } },
    projection: { name: 1, email: 1 },
    limit: 20,
    explain: "executionStats"  // Optional
  }
  

• aggregate: Run aggregation pipelines

  javascriptCopy

  {
    collection: "orders",
    pipeline: [
      { $match: { status: "completed" } },
      { $group: { _id: "$customerId", total: { $sum: "$amount" } } }
    ],
    explain: "queryPlanner"  // Optional
  }
  

• count: Count matching documents

  javascriptCopy

  {
    collection: "products",
    query: { category: "electronics" }
  }
  

Write Operations

• update: Modify documents

  javascriptCopy

  {
    collection: "posts",
    filter: { _id: "60d21b4667d0d8992e610c85" },
    update: { $set: { title: "Updated Title" } },
    upsert: false,
    multi: false
  }
  

• insert: Add new documents

  javascriptCopy

  {
    collection: "comments",
    documents: [
      { author: "user123", text: "Great post!" },
      { author: "user456", text: "Thanks for sharing" }
    ]
  }
  

• createIndex: Create collection indexes

  javascriptCopy

  {
    collection: "users",
    indexes: [
      {
        key: { email: 1 },
        unique: true,
        name: "email_unique_idx"
      }
    ]
  }
  

System Operations

• serverInfo: Get MongoDB server details
  javascriptCopy

  {
    includeDebugInfo: true  // Optional
  }
  

Debugging

Since MCP servers communicate over stdio, debugging can be challenging. Use the MCP Inspector for better visibility:

npm run inspector

This will provide a URL to access the debugging tools in your browser.

Running evals

The evals package loads an mcp client that then runs the index.ts file, so there is no need to rebuild between tests. You can load environment variables by prefixing the npx command. Full documentation can be found here.

OPENAI_API_KEY=your-key  npx mcp-eval src/evals/evals.ts src/schemas/tools.ts

License

This MCP server is licensed under the MIT License. This means you are free to use, modify, and distribute the software, subject to the terms and conditions of the MIT License. For more details, please see the LICENSE file in the project repository.