# System Integration Validator

> Validates system integration before deployment. Use when checking ports, database connections, frontend-backend APIs, or debugging blocked/stuck workflows. Detects dead ends, bottlenecks, circular dependencies.

- Skill: `majiayu000/system-integration-validator` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add majiayu000/system-integration-validator`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/system-integration-validator/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/system-integration-validator

---


# System Integration Validator

## Pre-Deployment Checklist

1. **Ports** - All required ports free
2. **Database** - Connection, pool, migrations OK
3. **API Contract** - Frontend ↔ Backend match
4. **Data Flow** - No dead ends or loops

## Port Check
```bash
for port in 3000 3001 5432 6379 8080; do
  lsof -i :$port > /dev/null 2>&1 && echo "⚠️ $port IN USE" || echo "✅ $port free"
done
```

## Database Check
```bash
pg_isready -h localhost -p 5432 && echo "✅ PostgreSQL OK"
redis-cli ping && echo "✅ Redis OK"
```

## Flow Analysis

Look for:
- **Dead ends**: Output never consumed
- **Orphan inputs**: Input never provided
- **Bottlenecks**: High in-degree (>3 inputs)
- **Circular deps**: A → B → A

## Common Blocks
```typescript
// ❌ No timeout
await fetch(url)

// ✓ With timeout
const ctrl = new AbortController()
setTimeout(() => ctrl.abort(), 5000)
await fetch(url, { signal: ctrl.signal })
```