Calendar

Libre WebUI includes a personal calendar. Every signed-in user gets their own month and week views with one-off and recurring events, and scheduled automations project their upcoming occurrences and run history onto the same grid.

Events

An event has a title, optional notes, a start time, an optional end time, an all-day flag, and an optional recurrence rule. Titles and notes are encrypted at rest with the same envelope used for chats and notes.

Recurrence uses the shared trigger model:

Kind	Fields	Meaning
once	at	A single occurrence
hourly	minute, startHour?, endHour?	Every hour within a window
daily	hour, minute	Every day at a wall-clock time
weekly	dayOfWeek, hour, minute	Every week on a chosen day
monthly	dayOfMonth, hour, minute	Every month on a chosen day
yearly	month, dayOfMonth, hour, minute	Every year on a chosen date

Recurring events are stored once. Range queries expand them server-side: each projected occurrence carries a baseEventId pointing back to its source event, so editing the source updates every future occurrence. A dayOfMonth past the end of a month clamps to that month's last day. All recurrence math uses the server's local timezone.

Named calendars and sharing

Beyond the default personal scope, a user can create up to 20 named calendars, each with an optional display color. Events carry an optional calendarId; events without one live in the default scope, which stays private.

Named calendars share through the common grant model: a read grant lets the recipient see the calendar and its events alongside their own, and a write grant additionally lets them create and edit events in it. Events created by a collaborator are stored under the calendar owner's account, so quotas, deletion, and the portable archive stay owner-scoped. Access is re-authorized on every request; revoking a grant hides the calendar on the next read. Deleting a calendar detaches its events back to the owner's default scope and removes its grants.

Reminders

An event can carry a reminder offset (reminderMinutes, up to 14 days). The automation scheduler's leased tick sweeps due reminders and publishes a calendar-reminder notification to the event owner's inbox; a per-occurrence compare-and-set guarantees each occurrence never re-fires, including for recurring events.

ICS import and export

GET /api/calendar/export?calendarId= downloads a calendar (or the default scope) as an RFC 5545 .ics file: UTC timestamps, escaped text, basic RRULEs mapped from the native recurrence kinds, and VALARM blocks for reminders. POST /api/calendar/import accepts an ICS payload (up to 2 MB / 1,000 events) into a writable calendar scope. The importer handles UTC and floating times, all-day DATE values, and simple FREQ rules; rules it cannot represent faithfully (INTERVAL, COUNT, UNTIL, EXDATE) import the event without recurrence and are counted in the response as dropped rules rather than silently drifting.

Model access

Three built-in chat tools give models calendar access under the invoking user's identity: list_calendar_events (read-only), create_calendar_event, and delete_calendar_event (both side-effecting and therefore behind the standard tool-approval flow).

API

All endpoints require authentication. Event reads cover the caller's own events plus calendars shared with them; writes require ownership or a write grant on the target calendar.

Method	Path	Purpose
GET	/api/calendar/events?from=&to=	Events in a range, recurrence expanded
POST	/api/calendar/events	Create an event
PUT	/api/calendar/events/:eventId	Update an event
DELETE	/api/calendar/events/:eventId	Delete an event
GET	/api/calendar/calendars	Own and shared named calendars
POST	/api/calendar/calendars	Create a named calendar
PUT	/api/calendar/calendars/:id	Rename or recolor a calendar
DELETE	/api/calendar/calendars/:id	Delete a calendar (events detach)
GET	/api/calendar/export	ICS export
POST	/api/calendar/import	ICS import

Range queries take epoch-millisecond from/to bounds and span at most 13 months per request. A user may store up to 2000 events; titles are limited to 200 characters and notes to 10,000.