MariaDB / MySQL MCP Server

This MCP server exposes MariaDB and MySQL databases to MCP clients such as Claude Desktop, VS Code, and other compatible tools.

It provides tools to:

• list available databases
• list tables in a database
• describe table schemas
• execute SQL queries

Features

• Safe-by-default behavior: read-only access is enabled by default
• Query validation to block disallowed statements and reduce injection risk
• Configurable write permissions through environment variables
• Timeout and row-limit protection
• Numeric safety for insert IDs and BIGINT values returned by the MariaDB driver

Installation

Option 1: Install from npm

npm install -g mariadb-mcp-server

Option 2: Install locally

npm install mariadb-mcp-server

Option 3: Build from source

git clone https://github.com/rjsalgado/mariadb-mcp-server.git
cd mariadb-mcp-server
npm install
npm run build

Configuration

Set the following environment variables before starting the server:

• MARIADB_HOST: Database host
• MARIADB_PORT: Database port (default: 3306)
• MARIADB_USER: Database username
• MARIADB_PASSWORD: Database password
• MARIADB_DATABASE: Default database name (optional)
• MARIADB_ALLOW_INSERT: Enable INSERT statements (true/false)
• MARIADB_ALLOW_UPDATE: Enable UPDATE statements (true/false)
• MARIADB_ALLOW_DELETE: Enable DELETE statements (true/false)
• MARIADB_TIMEOUT_MS: Query timeout in milliseconds (default: 10000)
• MARIADB_ROW_LIMIT: Maximum number of rows returned (default: 1000)

Example:

export MARIADB_HOST=localhost
export MARIADB_PORT=3306
export MARIADB_USER=myuser
export MARIADB_PASSWORD=mypassword
export MARIADB_DATABASE=mydb
export MARIADB_ALLOW_INSERT=false
export MARIADB_ALLOW_UPDATE=false
export MARIADB_ALLOW_DELETE=false
export MARIADB_TIMEOUT_MS=10000
export MARIADB_ROW_LIMIT=1000

MCP configuration

Using npm package

{
  "mcpServers": {
    "mariadb": {
      "command": "npx",
      "args": ["mariadb-mcp-server"],
      "env": {
        "MARIADB_HOST": "your-host",
        "MARIADB_PORT": "3306",
        "MARIADB_USER": "your-user",
        "MARIADB_PASSWORD": "your-password",
        "MARIADB_DATABASE": "your-database",
        "MARIADB_ALLOW_INSERT": "false",
        "MARIADB_ALLOW_UPDATE": "false",
        "MARIADB_ALLOW_DELETE": "false",
        "MARIADB_TIMEOUT_MS": "10000",
        "MARIADB_ROW_LIMIT": "1000"
      },
      "disabled": false,
      "autoApprove": []
    }
  }
}

Using a built local server

{
  "mcpServers": {
    "mariadb": {
      "command": "node",
      "args": ["/absolute/path/to/mariadb-mcp-server/dist/index.js"],
      "env": {
        "MARIADB_HOST": "your-host",
        "MARIADB_PORT": "3306",
        "MARIADB_USER": "your-user",
        "MARIADB_PASSWORD": "your-password",
        "MARIADB_DATABASE": "your-database",
        "MARIADB_ALLOW_INSERT": "false",
        "MARIADB_ALLOW_UPDATE": "false",
        "MARIADB_ALLOW_DELETE": "false",
        "MARIADB_TIMEOUT_MS": "10000",
        "MARIADB_ROW_LIMIT": "1000"
      },
      "disabled": false,
      "autoApprove": []
    }
  }
}

Available tools

The server registers the following MCP tools:

list_databases

Lists all databases accessible to the configured user.

list_tables

Lists tables from a specific database.

Parameters:

• database (optional): database name to inspect

describe_table

Returns the schema of a specific table.

Parameters:

• database (optional): database name
• table (required): table name

execute_query

Executes a SQL query.

Parameters:

• database (optional): database name
• query (required): SQL statement to run

Testing

The repository includes scripts to validate the server against a MariaDB or MySQL instance.

npm run test:setup
npm run test:tools

Or run everything together:

npm test

Notes

• The server is safe-by-default and only allows read-only operations unless the write flags are explicitly enabled.
• Write operations are still subject to query validation and runtime limits.

Troubleshooting

If you encounter issues:

1. Check the server logs for error messages
2. Verify your MariaDB/MySQL credentials and connection details
3. Ensure your MariaDB/MySQL user has appropriate permissions
4. Check that your query is read-only and properly formatted

Inspiration https://github.com/dpflucas/mysql-mcp-server

License

This project is licensed under the MIT License - see the LICENSE file for details.