Ai-skills mssql

Execute read-only SQL queries against multiple Microsoft SQL Server databases. Use when: (1) querying MSSQL/SQL Server 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 "$T/skills/mssql" ~/.claude/skills/sanjay3290-ai-skills-mssql && rm -rf "$T"

manifest: skills/mssql/SKILL.md

source content

MSSQL Read-Only Query Skill

Execute safe, read-only queries against configured Microsoft SQL Server databases.

Requirements

Python 3.8+
pymssql:
```
pip install -r requirements.txt
```

Setup

Create

connections.json

in the skill directory or

~/.config/claude/mssql-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": 1433,
      "database": "app_prod",
      "user": "readonly_user",
      "password": "your-password",
      "encrypt": true,
      "tds_version": "7.3"
    }
  ]
}

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: 1433)
database	Yes	Database name
user	Yes	Username
password	Yes	Password
encrypt	No	Enable TLS encryption (default: false)
tds_version	No	TDS protocol version: 7.0, 7.1, 7.2, 7.3, 7.4 (default: auto)

Usage

List configured databases

python3 scripts/query.py --list

Query a database

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

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

Note: MSSQL uses

TOP N

instead of

LIMIT

. The

--limit

flag automatically inserts

TOP N

after SELECT.

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 enforcement: Query validation blocks write operations (use a
```
db_datareader
```
role user for server-side protection)
Query validation: Only SELECT, SHOW, EXPLAIN, WITH, SP_HELP queries allowed
Single statement: Multiple statements per query rejected
TLS support: Configurable encryption for secure connections
Query timeout: 30-second timeout enforced via pymssql
Connection timeout: 10-second login timeout
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
TDS version error	Try `"tds_version": "7.3"` or `"7.4"`
Encryption error	Set `"encrypt": true` for Azure SQL
Permission warning	Run `chmod 600 connections.json`

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
```
(auto-converts to TOP N)