# Time zones

> Stored times are UTC; the workspace time zone turns them into local dates for people and agents.

Every timestamp is stored in UTC. People mean their own time zone, so each workspace has one (Settings → Time zone, or `set_timezone`).

- The query store gives every event a `local_date` (`YYYY-MM-DD`) and `local_time` (ISO with offset) in the workspace zone. "Saturday" is `WHERE local_date = '2026-09-26'`.
- `resolve_time_range` turns a local date or period (`yesterday`, `last_week`, `last_7_days`, `this_month`, or from/to) into exact UTC bounds and a ready SQL condition, with daylight saving handled.
- The MCP `status` tool reports the zone, and `query` takes a `time_range` like `yesterday`. Over HTTP: `GET /v1/capabilities` and `GET /v1/time`.
- The Home chart and the event log's day filter use local days.

```bash
curl -H "Authorization: Bearer $TOKEN" "https://usecoordinate.com/v1/time?relative=yesterday"
```