MongoDB MCP Server: Query MongoDB and Atlas with Claude

The MongoDB MCP Server is MongoDB’s official Model Context Protocol server for MongoDB databases and MongoDB Atlas. It lets Claude run find and aggregation queries, describe collection schemas and indexes, explain query plans, and, with Atlas credentials, list and manage clusters, projects and database users.

Who it is for

Developers who use MongoDB locally or on Atlas and want Claude Code to understand their real data shape before writing queries or index changes.

Install

The README offers three routes. The simplest is the interactive setup script, which asks for your connection string or Atlas API credentials:

npx -y mongodb-mcp-server@latest setup

The README also lists official MongoDB plugins for Claude: mongodb-atlas connects to the hosted Atlas MCP server over OAuth, and mongodb runs the server locally for self-managed deployments.

For manual setup, the README’s config with a connection string looks like this. It works as a project .mcp.json in Claude Code:

{
  "mcpServers": {
    "MongoDB": {
      "command": "npx",
      "args": ["-y", "mongodb-mcp-server@latest", "--readOnly"],
      "env": {
        "MDB_MCP_CONNECTION_STRING": "mongodb://localhost:27017/myDatabase"
      }
    }
  }
}

MongoDB recommends environment variables over command-line arguments for secrets, because arguments can show up in process lists and logs.

Use cases

• Understand data: “Describe the schema of the orders collection and show a sample document.”
• Query help: Claude writes and runs an aggregation, then explains the result.
• Index tuning: run explain on a slow query and ask for an index suggestion.
• Atlas admin: list clusters, check alerts or read Performance Advisor tips.

Pros

• Official, Apache-2.0 licensed and actively released.
• Read-only mode in every documented example.
• Covers local MongoDB, Atlas, Atlas Local and Atlas Stream Processing.
• Includes a MongoDB knowledge-base search tool for docs questions.

Cons and caveats

• Write tools include drop-database and delete-many. Keep --readOnly unless you need writes.
• Atlas tools need a service account. Give it only the minimum permissions.
• The hosted Atlas server needs a client with OAuth, or the separate mongodb-atlas-mcp-remote package.
• Large query results use up context. Ask for counts or samples first.

Links

• Repo: mongodb-js/mongodb-mcp-server
• Docs: MongoDB MCP Server
• Package: mongodb-mcp-server on npm
• Related: DBHub, Supabase MCP, MCP servers guide

Checked 24 Oct 2026 against the vendor repo, the MongoDB docs and the MCP registry.