Read the calendar — the day's agenda, what's on, how busy you are, your availability, an overview of a day or week, where your time goes. Returns, in one call, everything needed to reason about the plan: the current time (`now`), the user's `areas` and `activityTypes`, `userPreferences`, and a `days` array (each day's events, free slots, and how its time splits across areas/types — blocking load and any non-blocking overlay load reported separately). Call it before scheduling to anchor relative times ('this afternoon'). Defaults to today; pass `date` for another single day, `from`+`to` for an inclusive range, or `dates` for a specific set (ISO YYYY-MM-DD). Pass `compact: true` to shrink events for wide ranges, or `includeSeries: true` to also get recurring masters as `series`. Each event carries its `source` ("reassign", else a provider like "google") and, when calendar-linked, its `calendar` name; an event with `readOnly: true` is on a calendar the user doesn't own — don't edit or delete it (tell them to change it there). `kind` is omitted for a normal blocking event; "non-blocking" is an overlay that may overlap others (fasting, an away marker); "reference" is see-only — its hours stay free, don't move/delete/schedule work into it unless asked. A confirmed past day carries a `review` adherence rollup plus per-event `reflect` actuals (an unreviewed day has neither) — use it for how a day or week actually went. When a calendar is connected, `integrations` describes it (connected sources + their calendars, classification fallbacks, and the default sync target); omitted otherwise. For a single day, a one-line `weather` headline is included when the user has a city — call get_weather only for hourly detail. `backlogCount` reports how many parked blocks (the inbox of un-timed intentions) the user has; pass `includeBacklog: true` for the items (top of tray first, up to 50) or `backlogQuery` to find one by name — place/manage them with manage_backlog. Times are in the user's `timezone`; an untitled event shows as "(untitled)".