Ai-skills postgres

Execute read-only SQL queries against multiple PostgreSQL databases. Use when: (1) querying PostgreSQL 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 "$T/skills/postgres" ~/.claude/skills/sanjay3290-ai-skills-postgres && rm -rf "$T"
manifest: skills/postgres/SKILL.md
source content

PostgreSQL Read-Only Query Skill

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

Requirements

  • Python 3.8+
  • psycopg2-binary:
    pip install -r requirements.txt

Setup

Create

connections.json
in the skill directory or
~/.config/claude/postgres-connections.json
.

Security: Set file permissions to

600
since it contains credentials:

chmod 600 connections.json
{
  "databases": [
    {
      "name": "production",
      "description": "Main app database - users, orders, transactions",
      "host": "db.example.com",
      "port": 5432,
      "database": "app_prod",
      "user": "readonly_user",
      "password": "your-password",
      "sslmode": "require"
    }
  ]
}

Config Fields

FieldRequiredDescription
nameYesIdentifier for the database (case-insensitive)
descriptionYesWhat data this database contains (used for auto-selection)
hostYesDatabase hostname
portNoPort number (default: 5432)
databaseYesDatabase name
userYesUsername
passwordYesPassword
sslmodeNoSSL mode: disable, allow, prefer (default), require, verify-ca, verify-full

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 aboutLook for description containing
users, accountsusers, accounts, customers
orders, salesorders, transactions, sales
analytics, metricsanalytics, metrics, reports
logs, eventslogs, events, audit

If unclear, run

--list
and ask user which database.

Safety Features

  • Read-only session: Connection uses PostgreSQL
    readonly=True
    mode (primary protection)
  • Query validation: Only SELECT, SHOW, EXPLAIN, WITH queries allowed
  • Single statement: Multiple statements per query rejected
  • SSL support: Configurable SSL mode for encrypted connections
  • Query timeout: 30-second statement timeout enforced
  • 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

ErrorSolution
Config not foundCreate
connections.json
in skill directory
Authentication failedCheck username/password in config
Connection timeoutVerify host/port, check firewall/VPN
SSL errorTry
"sslmode": "disable"
for local databases
Permission warningRun
chmod 600 connections.json

Exit Codes

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

Workflow

  1. Run
    --list
    to show available databases
  2. Match user intent to database description
  3. Run
    --tables
    or
    --schema
    to explore structure
  4. Execute query with appropriate LIMIT