Ai-skills mysql

Execute read-only SQL queries against multiple MySQL databases. Use when: (1) querying MySQL databases, (2) exploring database schemas/tables, (3) running SELECT queries for data analysis, (4) checking database contents. Supports multiple database connections with descriptions for intelligent auto-selection. Blocks all write operations (INSERT, UPDATE, DELETE, DROP, etc.) for safety.

install

source · Clone the upstream repo

git clone https://github.com/sanjay3290/ai-skills

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/sanjay3290/ai-skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/mysql" ~/.claude/skills/sanjay3290-ai-skills-mysql && rm -rf "$T"

manifest: skills/mysql/SKILL.md

source content

MySQL Read-Only Query Skill

Execute safe, read-only queries against configured MySQL databases.

Requirements

Python 3.8+
mysql-connector-python:
```
pip install -r requirements.txt
```

Setup

Create

connections.json

in the skill directory or

~/.config/claude/mysql-connections.json

Security: Set file permissions to

since it contains credentials:

chmod 600 connections.json

{
  "databases": [
    {
      "name": "production",
      "description": "Main app database - users, orders, transactions",
      "host": "db.example.com",
      "port": 3306,
      "database": "app_prod",
      "user": "readonly_user",
      "password": "your-password",
      "ssl_disabled": false
    }
  ]
}

Config Fields

Field	Required	Description
name	Yes	Identifier for the database (case-insensitive)
description	Yes	What data this database contains (used for auto-selection)
host	Yes	Database hostname
port	No	Port number (default: 3306)
database	Yes	Database name
user	Yes	Username
password	Yes	Password
ssl_disabled	No	Set to `true` to disable SSL (default: false)
ssl_ca	No	Path to CA certificate file
ssl_cert	No	Path to client certificate file
ssl_key	No	Path to client private key file

Usage

List configured databases

python3 scripts/query.py --list

Query a database

python3 scripts/query.py --db production --query "SELECT * FROM users LIMIT 10"

List tables

python3 scripts/query.py --db production --tables

Show schema

python3 scripts/query.py --db production --schema

Limit results

python3 scripts/query.py --db production --query "SELECT * FROM orders" --limit 100

Database Selection

Match user intent to database

description

User asks about	Look for description containing
users, accounts	users, accounts, customers
orders, sales	orders, transactions, sales
analytics, metrics	analytics, metrics, reports
logs, events	logs, events, audit

If unclear, run

--list

and ask user which database.

Safety Features

Read-only session: Connection uses MySQL
```
SET SESSION TRANSACTION READ ONLY
```
(primary protection)
Query validation: Only SELECT, SHOW, DESCRIBE, EXPLAIN, WITH queries allowed
Single statement: Multiple statements per query rejected
SSL support: Configurable SSL with CA, client cert, and key support
Query timeout: 30-second max_execution_time enforced (MySQL 5.7.8+)
Memory protection: Max 10,000 rows per query to prevent OOM
Column width cap: 100 char max per column for readable output
Credential sanitization: Error messages don't leak passwords

Troubleshooting

Error	Solution
Config not found	Create `connections.json` in skill directory
Authentication failed	Check username/password in config
Connection timeout	Verify host/port, check firewall/VPN
SSL error	Try `"ssl_disabled": true` for local databases
Permission warning	Run `chmod 600 connections.json`
max_execution_time not supported	Upgrade to MySQL 5.7.8+ or MariaDB 10.1.1+

Exit Codes

0: Success
1: Error (config missing, auth failed, invalid query, database error)

Workflow

Run
```
--list
```
to show available databases
Match user intent to database description
Run
```
--tables
```
or
```
--schema
```
to explore structure
Execute query with appropriate LIMIT