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