Calendar Automation

Create, read, update, and delete events in Apple Calendar.app using AppleScript.

Quick Reference

Create Event

applescript

set theStartDate to (current date) + (1 * days)
set hours of theStartDate to 14
set minutes of theStartDate to 0
set seconds of theStartDate to 0
set theEndDate to theStartDate + (2 * hours)

with timeout of 15 seconds
    tell application "Calendar"
        tell calendar "Personal"
            set e to make new event with properties {¬
                summary:"Meeting title", ¬
                start date:theStartDate, ¬
                end date:theEndDate, ¬
                location:"123 Main St, City, CA 90000", ¬
                description:"Notes here"¬
            }
            return uid of e
        end tell
    end tell
end timeout

Read Events

applescript

-- List calendars
tell application "Calendar" to name of every calendar

-- Find by summary
tell application "Calendar"
    tell calendar "Personal"
        first event whose summary contains "Meeting"
    end tell
end tell

-- Today's events
set theStart to current date
set hours of theStart to 0
set minutes of theStart to 0
set seconds of theStart to 0
set theEnd to theStart + (1 * days) - 1

tell application "Calendar"
    tell calendar "Personal"
        every event where its start date >= theStart and end date <= theEnd
    end tell
end tell

Update Event

applescript

with timeout of 15 seconds
    tell application "Calendar"
        tell calendar "Personal"
            set e to first event whose summary contains "Meeting"
            set summary of e to "Updated title"
            set location of e to "New location"
            -- IMPORTANT: Update end date BEFORE start date
            set end date of e to newEndDate
            set start date of e to newStartDate
        end tell
    end tell
end timeout

Delete Event

applescript

with timeout of 15 seconds
    tell application "Calendar"
        tell calendar "Personal"
            delete (first event whose summary contains "Meeting")
        end tell
    end tell
end timeout

Event Properties

Property	Type	Notes
`summary`	text	Event title (required)
`start date`	date	Start datetime (required)
`end date`	date	End datetime (required)
`description`	text	Event notes
`location`	text	Standard street address for Maps integration (see Location Format section)
`url`	text	Link to related resource
`allday event`	boolean	Use this, not `isAllDay`
`uid`	text	Unique ID (read-only)

Date Calculations

applescript

-- Tomorrow at 2pm
set d to (current date) + (1 * days)
set hours of d to 14
set minutes of d to 0
set seconds of d to 0

-- Next Monday at 9am
set nextMonday to current date
repeat until weekday of nextMonday is Monday
    set nextMonday to nextMonday + (1 * days)
end repeat
set hours of nextMonday to 9
set minutes of nextMonday to 0

-- Durations
set later to now + (30 * minutes)
set later to now + (2 * hours)
set later to now + (7 * days)

Recurrence (RFC 5545)

applescript

-- Weekly on Mon/Wed, 8 times
set recurrence of e to "FREQ=WEEKLY;BYDAY=MO,WE;COUNT=8"

-- First Monday of each month, 6 times
set recurrence of e to "FREQ=MONTHLY;BYDAY=1MO;COUNT=6"

-- Every 2 weeks until date
set recurrence of e to "FREQ=WEEKLY;INTERVAL=2;UNTIL=20261231T235959Z"

Alarms

applescript

tell e
    make new display alarm with properties {trigger interval:-15}  -- 15 min before
    make new mail alarm with properties {trigger interval:-60}     -- 1 hour before
end tell

Critical Rules

•Always use timeout: Wrap Calendar operations in with timeout of 15 seconds
•Update order: Set end date BEFORE start date when rescheduling
•Delete syntax: Use inline delete (first event whose...) to avoid variable errors
•Property name: Use allday event, not isAllDay
•Bulk delete fails: Delete events one at a time, not as a list
•Always list calendars first: Run tell application "Calendar" to name of every calendar before assuming a calendar exists (e.g., "Personal" may not exist)
•No localized date strings: Never use date "2026年1月23日" — set components separately

Location Format (Apple Maps Integration)

Apple Calendar uses Apple Maps for location recognition. To ensure the location shows a map preview and enables navigation:

Required format: Street Number + Street Name, City, State ZIP

Format	Example	Recognized?
Standard address	`420 Westwood Plaza, Los Angeles, CA 90095`	✅ Yes
Descriptive name	`UCLA Samueli School of Engineering, Los Angeles, CA`	❌ No
Building only	`Boelter Hall`	❌ No
Internal address	`7400 Boelter Hall`	❌ No

For universities/campuses: Buildings have two address systems:

•Internal: Room# + Building Name (for mail/internal navigation)
•Street: Standard address (for Apple Maps)

Workflow to find standard address:

•Search: [Building Name] street address
•Check official contact page for street address
•Verify ZIP code is complete (e.g., 90095 not omitted)

AoE (Anywhere on Earth) Time Zone

Academic deadlines often use AoE (UTC-12). Convert to local time before creating events.

Conversion formula (for Los Angeles):

•PST (Nov–Mar): 23:59 AoE = next day 03:59 PST (+4 hours, +1 day)
•PDT (Mar–Nov): 23:59 AoE = next day 04:59 PDT (+5 hours, +1 day)

Example: "Jan 28, 23:59 AoE" → Create event at Jan 29, 03:59 PST

applescript

-- Convert "Jan 28, 23:59 AoE" to local time (PST)
set d to current date
set year of d to 2026
set month of d to 1
set day of d to 29      -- Next day
set hours of d to 3     -- 03:59 for PST (or 04:59 for PDT)
set minutes of d to 59
set seconds of d to 0

Best practice: Include original AoE time in event description for reference:

code

Original: Jan 28, 23:59 AoE (UTC-12)
Local: Jan 29, 03:59 PST

Calendar Naming Convention

Follow the Event as Data (EaD) protocol when creating events:

Summary format: [Project_ID] Action_Verb - Specific_Task

Examples:

•[CS301] Submit - Assignment 4
•[Landlord_Case] Call - Schedule mediation
•[mineflayer_bot] Debug - Pathfinding module

For detailed reference: See references/calendar_reference.md.