self-monitor

Compatible with Claude Code, Codex CLI, Cursor, Windsurf, and any SKILL.md-compatible agent.

Self Monitor

Proactive self-monitoring: infrastructure, services, and health.

Usage

Run during heartbeats or scheduled checks.

1. Infrastructure Health

# Disk usage
df -h / | awk 'NR==2 {print $5}' | tr -d '%'

# Memory usage  
free -m | awk 'NR==2 {printf "%.0f", $3/$2*100}'

# Load average
uptime | awk -F'load average:' '{print $2}' | awk -F',' '{print $1}'

# Top processes by memory
ps aux --sort=-%mem | head -10

# Top processes by CPU
ps aux --sort=-%cpu | head -10

Thresholds:

Metric	Warning	Critical
Disk	> 80%	> 90%
Memory	> 85%	> 95%
Load	> 2.0	> 4.0

2. Service Health

# Check if a process is running
pgrep -f "your_process_name" >/dev/null && echo "OK" || echo "FAIL"

# Check HTTP endpoint
curl -s -o /dev/null -w "%{http_code}" http://localhost:8080/health

# Check systemd service
systemctl is-active --quiet nginx && echo "OK" || echo "FAIL"

# Check Docker container
docker ps --filter "name=mycontainer" --filter "status=running" -q | grep -q . && echo "OK" || echo "FAIL"

# Tailscale (if using)
tailscale status --json 2>/dev/null | jq -r '.Self.Online' || echo "FAIL"

3. Cron Job Health

# Check recent cron executions
grep CRON /var/log/syslog | tail -20

# Count failures in last 24h
grep -c "CRON.*error\|CRON.*fail" /var/log/syslog

# List scheduled jobs
crontab -l

4. Recent Errors

# Check system logs for errors
journalctl -p err --since "1 hour ago" 2>/dev/null | tail -20

# Check application logs
tail -50 ~/projects/*/logs/*.log 2>/dev/null | grep -i "error"

# Check dmesg for hardware/kernel issues
dmesg | tail -20 | grep -i "error\|fail\|warn"

Quick Health Check (for heartbeat)

#!/bin/bash
# Quick health snapshot

DISK=$(df -h / | awk 'NR==2 {print $5}' | tr -d '%')
MEM=$(free -m | awk 'NR==2 {printf "%.0f", $3/$2*100}')
LOAD=$(uptime | awk -F'load average:' '{print $2}' | awk -F',' '{print $1}' | xargs)

echo "Disk: ${DISK}% | Mem: ${MEM}% | Load: ${LOAD}"

# Alert if thresholds exceeded
[ "$DISK" -gt 90 ] && echo "⚠️ Disk critical!"
[ "$MEM" -gt 95 ] && echo "⚠️ Memory critical!"