GA4 Data API v1 — runReport The Data API v1 is the canonical read path for GA4. One endpoint ( ) covers most use cases. Two paths matter for picking the right query: dimensions describe rows (date, page, source), metrics describe values (sessions, users, events). Not every combination is valid — see "Compatibility" below. Prerequisite: auth working (see ). The minimum viable query That's the full skeleton. Everything below extends this shape. The 12 metrics worth knowing | Metric | What it counts | Notes | |---|---|---| | | Unique users with engagement in the window | The "users" people mean…