promql
Installation
SKILL.md
PromQL
PromQL is Prometheus's functional query language. This skill covers homelab usage with node-exporter, cAdvisor/Docker metrics, and app-specific exporters (Plex, Sonarr, Radarr, Prowlarr, Home Assistant, AdGuard Home).
Data Types
| Type | Description | When you have it |
|---|---|---|
| Instant vector | One sample per series at current time | Bare metric name or {} selector |
| Range vector | Multiple samples over a window | Metric with [5m] appended |
| Scalar | Single number | scalar(), arithmetic on instant vectors |
| String | Unused in practice | — |
Range vectors can only be passed to functions (rate, avg_over_time, etc.) — they can't be graphed directly.