mysql-mcp

MySQL MCP Server for OpenAI Codex — Create, Read, Update only. No destructive operations.

Directory Tree

mysql-mcp/
├── .codex/
│   └── config.toml          ← Codex MCP registration
├── src/
│   ├── server/
│   │   ├── index.ts         ← MCP server entry (stdio transport)
│   │   ├── db.ts            ← mysql2 connection pool + query helpers
│   │   └── tools/
│   │       ├── schema.ts    ← mysql_list_databases, mysql_list_tables, mysql_describe_table
│   │       ├── read.ts      ← mysql_query  (SELECT only)
│   │       └── write.ts     ← mysql_insert, mysql_update  (no DELETE/DROP)
│   └── client/
│       └── index.ts         ← Test client — launches server + runs all tools
├── .env.example             ← Copy to .env with your credentials
├── .gitignore
├── package.json
└── tsconfig.json

Tools

Setup

# 1. Install dependencies
npm install

# 2. Configure credentials
cp .env.example .env
# edit .env with your MySQL details

# 3. Run the test client (launches server automatically)
npm run client

# 4. Or run server standalone
npm run server

Registering with Codex

Edit .codex/config.toml with your credentials — Codex will auto-launch the server.

Or register via CLI:

codex mcp add mysql \
  --env MYSQL_HOST=localhost \
  --env MYSQL_USER=mcp_user \
  --env MYSQL_PASSWORD=secret \
  --env MYSQL_DATABASE=mydb \
  -- npx tsx /path/to/mysql-mcp/src/server/index.ts

Verify in Codex TUI: /mcp

Safety Guardrails

• mysql_query blocks INSERT/UPDATE/DELETE/DROP/TRUNCATE even if embedded in a SELECT
• mysql_update requires a WHERE clause — updates without a condition are rejected
• mysql_update supports dry_run: true to preview affected rows before committing
• All identifiers (table/column names) are sanitized against injection
• All values use ? prepared statement placeholders — never string interpolation
• No DELETE, TRUNCATE, DROP, or ALTER tools exist