db-readonly

name	db-readonly
description	Run safe read-only queries against MySQL or PostgreSQL for data inspection, reporting, and troubleshooting. Use when the user asks to read tables, inspect schema, count rows, sample data, or export query results without modifying data.

db-readonly

Use this skill for database read tasks only.

What this skill does

• Connect to PostgreSQL or MySQL using connection env vars
• Execute SELECT / WITH / EXPLAIN queries only
• Optionally save output to CSV/TSV/JSON
• Block risky SQL (INSERT, UPDATE, DELETE, DROP, ALTER, etc.)

Connection env vars

PostgreSQL

• PGHOST
• PGPORT (optional, default 5432)
• PGDATABASE
• PGUSER
• PGPASSWORD

MySQL

• MYSQL_HOST
• MYSQL_PORT (optional, default 3306)
• MYSQL_DATABASE
• MYSQL_USER
• MYSQL_PASSWORD

Run

Use script:

• scripts/db_readonly.sh postgres "SELECT now();"
• scripts/db_readonly.sh mysql "SELECT NOW();"

Export example:

• scripts/db_readonly.sh postgres "SELECT * FROM users LIMIT 100" --format csv --out /tmp/users.csv

Safety rules

1. Refuse non-read SQL.
2. Prefer LIMIT for exploratory queries.
3. When user asks for updates/deletes/schema changes, ask explicit confirmation and do not run via this skill.
4. Avoid printing secrets from env vars.

Reference

• Query cookbook: references/query-cookbook.md