# Health Check

> System health check dispatched by the activity monitor via Control queue. Checks PM2 services, disk space, and memory usage. Use when receiving a control message containing "health-check".

- Skill: `zylos-ai/health-check` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add zylos-ai/health-check`
- Raw SKILL.md: https://api.skillmd.com/api/skills/zylos-ai/health-check/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: zylos-ai (https://skillmd.com/u/zylos-ai)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/zylos-ai/health-check

---


# System Health Check

Periodic system health check delivered via the C4 Control queue.

## When to Use

- Receiving a control message with "health-check" in the content
- The activity monitor enqueues this automatically at regular intervals

## Steps

### 1. Check PM2 Services

```bash
pm2 jlist
```

Parse the JSON output. Every service should have `status: "online"`.
Record which services are stopped or errored.

### 2. Check Disk Space

```bash
df -h / /home 2>/dev/null || df -h /
```

Thresholds:
- OK: < 80% used
- Warning: 80-90% used
- Critical: > 90% used

### 3. Check Memory

```bash
free -m
```

Thresholds:
- OK: < 80% used
- Warning: 80-90% used
- Critical: > 90% used (or swap > 50% used)

### 4. Report Results

If all checks pass, log to `~/zylos/logs/health.log`:

```
[YYYY-MM-DD HH:MM:SS] Health Check: PM2 X/X online, Disk XX%, Memory XX% - ALL OK
```

If any issues found, notify whoever is most likely to help:
1. Check your memory files for a designated owner or ops person
2. If none designated, notify the person you normally work with most
3. Use `c4-send.js` with the appropriate channel and endpoint to send the alert

## Issue Resolution

| Issue | Action |
|-------|--------|
| PM2 service stopped | `pm2 restart <service>` and report |
| High disk usage | Check logs directories, report findings |
| High memory / swap | Report findings, check for runaway processes |