PromQL

PromQL is a nested functional language for selecting and aggregating Prometheus time series. Every query is an expression tree: selectors at the leaves, functions and operators at the nodes, a single root value (scalar, instant vector, range vector, or string) at the top. Type discipline makes queries correct; cardinality awareness makes them fast.

Authoritative reference for writing PromQL queries — dashboards, alerts, recording rules, exploration. The companion backend/prometheus skill covers instrumentation (metric types, naming, labels, exporters). When both apply, use backend/prometheus for emitting metrics and this skill for querying them.

References