PostgreSQL

A Model Context Protocol server that provides read-only access to PostgreSQL databases. This server enables LLMs to inspect database schemas and execute read-only queries.

Components

Tools

• query
  • Execute read-only SQL queries against the connected database
  • Input: sql (string): The SQL query to execute
  • All queries are executed within a READ ONLY transaction

Resources

The server provides schema information for each table in the database:

• Table Schemas (postgres://<host>/<table>/schema)
  • JSON schema information for each table
  • Includes column names, data types, sizes, nullability, and default values.
  • Automatically discovered from database metadata

Configuration

Usage with Claude Desktop

To use this server with the Claude Desktop app, add the following configuration to the "mcpServers" section of your claude_desktop_config.json:

Docker

• when running docker on macos, use host.docker.internal if the server is running on the host network (eg localhost)
• username/password can be added to the postgresql url with postgresql://user:password@host:port/db-name

{
  "mcpServers": {
    "postgres": {
      "command": "docker",
      "args": [
        "run", 
        "-i", 
        "--rm", 
        "mcp/postgres", 
        "postgresql://host.docker.internal:5432/mydb"]
    }
  }
}

NPX

{
  "mcpServers": {
    "postgres": {
      "command": "npx",
      "args": [
        "-y",
        "@lariat-software/mcp-server-postgresql",
        "postgresql://localhost/mydb"
      ]
    }
  }
}

Replace /mydb with your database name.

Usage with VS Code

For quick installation, use one of the one-click install buttons below...

For manual installation, add the following JSON block to your User Settings (JSON) file in VS Code. You can do this by pressing Ctrl + Shift + P and typing Preferences: Open User Settings (JSON).

Optionally, you can add it to a file called .vscode/mcp.json in your workspace. This will allow you to share the configuration with others.

Note that the mcp key is not needed in the .vscode/mcp.json file.

Docker

Note: When using Docker and connecting to a PostgreSQL server on your host machine, use host.docker.internal instead of localhost in the connection URL.

{
  "mcp": {
    "inputs": [
      {
        "type": "promptString",
        "id": "pg_url",
        "description": "PostgreSQL URL (e.g. postgresql://user:[email protected]:5432/mydb)"
      }
    ],
    "servers": {
      "postgres": {
        "command": "docker",
        "args": [
          "run",
          "-i",
          "--rm",
          "mcp/postgres",
          "${input:pg_url}"
        ]
      }
    }
  }
}

NPX

{
  "mcp": {
    "inputs": [
      {
        "type": "promptString",
        "id": "pg_url",
        "description": "PostgreSQL URL (e.g. postgresql://user:pass@localhost:5432/mydb)"
      }
    ],
    "servers": {
      "postgres": {
        "command": "npx",
        "args": [
          "-y",
          "@lariat-software/mcp-server-postgresql",
          "${input:pg_url}"
        ]
      }
    }
  }
}

Building

Docker:

docker build -t mcp/postgres -f src/postgres/Dockerfile . 

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.