mcp-server-mysql-schema

MySQL Schema MCP Server — explore tables, columns, foreign keys, indexes, and relationships through the Model Context Protocol. Works with opencode, Claude Desktop, Cursor, and any MCP-compatible AI client.

No more writing SHOW TABLES and DESCRIBE manually. Ask your AI assistant "what tables are in this database?", "show me the foreign keys of the orders table", or "find all columns named 'status'" — and get structured JSON responses.

Quick Start

# Install
npx mcp-server-mysql-schema

# Or clone
git clone [email protected]:rendi-febrian/mcp-server-mysql-schema.git
cd mcp-server-mysql-schema
npm install && npm run build

opencode Configuration

{
  "mcp": {
    "mysql-schema": {
      "type": "local",
      "command": ["node", "/path/to/mcp-server-mysql-schema/dist/index.js"],
      "environment": {
        "MYSQL_HOST": "127.0.0.1",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "root",
        "MYSQL_PASS": "your-password"
      },
      "enabled": true
    }
  }
}

Claude Desktop / Cursor / Other MCP Clients

{
  "mcpServers": {
    "mysql-schema": {
      "command": "node",
      "args": ["/path/to/mcp-server-mysql-schema/dist/index.js"],
      "env": {
        "MYSQL_HOST": "127.0.0.1",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "root",
        "MYSQL_PASS": "your-password"
      }
    }
  }
}

Features

Tools

| Tool | Description | Example | |---|---|---| | schema_databases | List all non-system databases with charset | schema_databases() | | schema_tables | All tables — engine, row count, auto-increment, comments | schema_tables(database: "myapp") | | schema_views | All views in a database | schema_views(database: "myapp") | | schema_table_detail | Columns: type, nullable, default, key, extra, comment | schema_table_detail(database: "myapp", table: "users") | | schema_foreign_keys | FK relationships — all DB, per-table, incoming/outgoing | schema_foreign_keys(database: "myapp", table: "orders") | | schema_indexes | Indexes: name, columns, seq, unique, type, comment | schema_indexes(database: "myapp", table: "users") | | schema_relationships | Full PK/FK map across all tables | schema_relationships(database: "myapp") | | schema_search | Search table and column names by keyword | schema_search(database: "myapp", keyword: "user") |

Resources

| URI | Content | |---|---| | schema://{db}/tables | All tables in the database | | schema://{db}/relationships | Full relationship map | | schema://{db}/{table}/columns | Column details | | schema://{db}/{table}/indexes | Index details | | schema://{db}/{table}/foreign-keys | Foreign key details |

Security

100% read-only. Every query targets information_schema only. No SELECT on user tables. No INSERT, UPDATE, DELETE, or DDL. The server cannot modify any data.

Why Not Just Use MySQL MCP?

| | MySQL MCP | Schema MCP (this) | |---|---|---| | Purpose | Run arbitrary SQL | Introspect database structure | | Query target | Any table / any query | information_schema only | | Write access | Optional (configurable) | Never | | Structured tools | Single mysql_query tool | 8 focused tools | | Resources | Table-level | Table + FK + relationship maps | | Best for | Data CRUD, ad-hoc queries | Schema discovery, ERD, migrations |

Requirements

• Node.js >= 18
• MySQL 5.7+ or MariaDB 10.2+
• MySQL user with SELECT on information_schema (default)

Environment Variables

| Variable | Required | Default | Description | |---|---|---|---| | MYSQL_HOST | No | 127.0.0.1 | MySQL host | | MYSQL_PORT | No | 3306 | MySQL port | | MYSQL_USER | No | root | MySQL user | | MYSQL_PASS | No | "" | MySQL password | | MYSQL_DEFAULT_DB | No | — | Default database for resource URIs |

Architecture

src/
├── index.ts              # MCP server entry point (raw Server)
├── db.ts                 # MySQL connection pool
├── schema.ts             # information_schema queries
├── tools/
│   ├── tables.ts         # schema_databases, schema_tables, schema_views
│   ├── detail.ts         # schema_table_detail
│   ├── foreignKeys.ts    # schema_foreign_keys
│   ├── indexes.ts        # schema_indexes
│   ├── relationships.ts  # schema_relationships
│   └── search.ts         # schema_search
└── resources/
    └── index.ts          # schema:// URIs

No ORM, no migrations, no configuration files — just raw information_schema queries over mysql2.

Contributing

See CONTRIBUTING.md.

License

MIT