@maxlmgc/mysql-mcp

MySQL MCP Server — a secure, read-only-by-default MySQL integration for AI clients via the Model Context Protocol.

中文文档

Tools

Tool	Description	Read-only mode
sql_query	Execute SELECT / SHOW / DESCRIBE / EXPLAIN queries	Allowed
sql_list_tables	List all tables in the current database	Allowed
sql_table_schema	Get column structure and comments of a table	Allowed
sql_execute	Execute INSERT / UPDATE / DELETE (auto-rolled back)	Blocked

Environment Variables

Database Connection (required)

Variable	Description	Default
MYSQL_HOST	Database host	-
MYSQL_PORT	Database port	3306
MYSQL_USER	Database user	-
MYSQL_PASS	Database password	(empty)
MYSQL_DB	Database name	-

Read-only Mode

Variable	Description	Default
MYSQL_READONLY	Set to false to disable read-only mode	true (enabled)
MYSQL_READONLY_PREFIXES	Custom SQL keyword whitelist (comma-separated, overrides defaults)	SELECT,SHOW,DESCRIBE,DESC,EXPLAIN,WITH

Connection Pool

Variable	Description	Default
MYSQL_CONNECTION_LIMIT	Max connections in pool	10
MYSQL_MULTIPLE_STATEMENTS	Set to false to disable multi-statement execution	true

Installation

npm install @maxlmgc/mysql-mcp

Usage

MCP Client Configuration

Add to your MCP client configuration:

{
  "mcpServers": {
    "mysql-mcp": {
      "command": "npx",
      "args": ["-y", "@maxlmgc/mysql-mcp"],
      "env": {
        "MYSQL_HOST": "localhost",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "root",
        "MYSQL_PASS": "your_password",
        "MYSQL_DB": "your_database"
      }
    }
  }
}

Read-only Mode (default)

By default only query operations are allowed; sql_execute is not exposed.

Disable Read-only Mode

"env": {
  "MYSQL_HOST": "localhost",
  "MYSQL_USER": "root",
  "MYSQL_DB": "your_database",
  "MYSQL_READONLY": "false"
}

Custom Whitelist

Only allow SELECT and SHOW:

"env": {
  "MYSQL_HOST": "localhost",
  "MYSQL_USER": "root",
  "MYSQL_DB": "your_database",
  "MYSQL_READONLY_PREFIXES": "SELECT,SHOW"
}

Security

• Read-only by default: sql_execute is not registered in read-only mode
• SQL injection prevention: Table names validated with regex; parameterized queries used
• Startup validation: Missing required env vars cause immediate failure
• Transaction rollback: sql_execute runs in a transaction that is always rolled back
• Dual-layer protection: SQL validation at both tool layer and connection pool layer

License

MIT