What is mcp-server-mysql CLAUDE.md?

Project instructions for an MCP server that lets language models access MySQL databases, including commands for building, running, testing, and development.

Use it when developing the server, building TypeScript, starting local or remote modes, setting up the test database, or running unit, integration, end-to-end, and socket tests.

It gives contributors the repository's expected commands and explains its main technologies and test setup.

How benborla/mcp-server-mysql configures Claude Code

About the project

mcp-server-mysql is a Model Context Protocol server that lets language models inspect MySQL database schemas and run read-only queries. It is used to give AI assistants controlled access to database information.

benborla/mcp-server-mysql · 2,206 stars · on GitHub

Reuse

Borrowing it

Nothing to install: this file belongs to benborla/mcp-server-mysql. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/benborla/mcp-server-mysql/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/benborla/mcp-server-mysql

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/benborla/mcp-server-mysql/claude-md/github.svg)](https://agentmods.dev/instructions/benborla/mcp-server-mysql/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/benborla/mcp-server-mysql/claude-md"><img src="https://agentmods.dev/badge/instructions/benborla/mcp-server-mysql/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/benborla/mcp-server-mysql/claude-md"><img src="https://agentmods.dev/badge/instructions/benborla/mcp-server-mysql/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 1,792 This file is loaded in full into every session.

When invoked 1,792 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.01792	$0.01792
Opus 5.5	$0.00717	$0.00717
Sonnet 5.5	$0.00358	$0.00358
Haiku 4.5	$0.00179	$0.00179

Measured 2mo ago against content hash 0cc9e6335642, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

mcp-server-mysql CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 250 lines

How it starts

The opening of the file, as written. The whole thing — 250 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

This is a Model Context Protocol (MCP) server that provides MySQL database access to LLMs like Claude, with enhanced write operation support and Claude Code optimizations.

Key Technologies:

TypeScript with ES Modules (NodeNext)
MCP SDK (@modelcontextprotocol/sdk v1.15.1)
mysql2 for database connectivity
Vitest for testing
Express for remote MCP mode (optional)

Build and Development Commands

Building

# Build TypeScript to dist/
pnpm build

# Watch mode (auto-rebuild on changes)
pnpm watch

Running

# Run built version
pnpm start

# Development mode with ts-node
pnpm dev

# Run directly with environment variables
pnpm exec

Testing

# Setup test database (creates mcp_test DB and seeds data)
pnpm run setup:test:db

# Run all tests (includes pretest hook that runs setup:test:db)
pnpm test

# Run specific test suites
pnpm test:unit          # Unit tests only
pnpm test:integration   # Integration tests only
pnpm test:e2e          # End-to-end tests only
pnpm test:socket       # Socket connection tests

# Watch mode for development
pnpm test:watch

# Coverage report
pnpm test:coverage

Test Environment Requirements:

MySQL server running locally or remotely
Test database user: mcp_test with password mcp_test_password
Test database: mcp_test
Configuration via .env.test file

Linting

pnpm lint

Architecture

Core Entry Point

index.ts - Main server file that exports createMcpServer() function
- Supports both stdio and HTTP transport modes
- Handles MCP protocol setup and request routing
- Configures shutdown handlers for graceful cleanup

Key Modules

Configuration (src/config/index.ts)

Loads environment variables via dotenv
Exports connection config, permission flags, and mode detection
Key exports:
- mcpConfig - MySQL connection configuration
- isMultiDbMode - Boolean indicating multi-database mode
- ALLOW_*_OPERATION - Global write permission flags
- SCHEMA_*_PERMISSIONS - Schema-specific permission maps
- MYSQL_DISABLE_READ_ONLY_TRANSACTIONS - Control transaction mode

Read the full file on GitHub · 250 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 250 lines · 1,792 tokens per session scan A 0cc9e6335642

Subscribe to this mod's changes

mcp-server-mysql CLAUDE.md is an instructions file published in the GitHub repository benborla/mcp-server-mysql (2,206 stars, last pushed 3mo ago), licensed MIT. It adds 1,792 tokens to every session, about $0.0072 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Databases

mcp-server-mysql CLAUDE.md next to 6 instructions from other repositories
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mcp-server-mysql CLAUDE.mdbenborla/mcp-server-mysql	Instructions file	2.2k	3mo ago	MIT	A	1,792	Claude Code
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mcp-server-mysql: Instructions file for Claude Code