Introduction

OverBooked is a desktop, keyboard-first planner that unifies contacts, events, and todos in one fast, modern interface.

It solves slow, click-heavy planning by letting you type to act - add/find/update in seconds, filter instantly, and link people to events/todos while spotting schedule overlaps at a glance. The appeal: crisp speed, minimal friction, and a workflow built for event planners who want proficiency without fuss.

📖 Table of Contents

Quick start

Follow these steps to get started with OverBooked in under 10 minutes:

  1. Install Java 17

    For Windows users:

    • Follow the Java Installation Guide.
    • To open PowerShell (Windows terminal), press the Windows key, type PowerShell, press Enter.
    • To verify that the installation was successful, close PowerShell, open it again, then run java -version. You should see something like java version "17.x.x".
    • If you have multiple versions of Java installed, refer to this Switching between Java versions Guide.

    For macOS users:

    • Follow the Java Installation Guide.
    • To open Terminal (macOS terminal), press ⌘ Space (Spotlight), type Terminal, press return.
    • To verify that the installation was successful, close Terminal, open it again, then run java -version. You should see the version information for Java 17.0.14.fx-zulu.
    • If you have multiple versions of Java installed, refer to this Switching between Java versions Guide. (Commands are to be run inside Terminal)

  2. Download the App

    • Find the latest version of OverBooked from our Releases Page, and click on OverBooked.jar which should start the download automatically.

  3. Set up your workspace

    • Go to your Downloads folder to verify that OverBooked.jar has been downloaded into your PC.
    • Drag and drop OverBooked.jar into a folder of your choice — this will be your OverBooked home folder.

  4. Run the app

    For Windows users:

    • Open the folder containing OverBooked.jar.
    • Double-click on OverBooked.jar to run the application.

    For macOS users:

    • In the Terminal window, type cd and press the return key.
    • Go back to Terminal and type cd and press the SpaceBar key, do not press the return key yet.
    • Open your Finder and locate the folder that contains OverBooked.jar.
    • Drag the folder that contains OverBooked.jar into the Terminal. This should paste some text into the Terminal window. Press the return key.
    • In the Terminal window, paste java -jar OverBooked.jar and press the return key.

    You should see a window like this:

    UI of the Main Window

  5. Try these Commands

    • help : Open the help window.
    • list-contacts : Lists all contacts.
    • add-contact n/John Doe p/98765432 e/johnd@example.com a/John street, block 123, #01-01 : Adds a contact named John Doe to the Address Book.
    • clear : Clears all entries in the book.
    • exit : Exits the app.

Refer to the Features below for details of each command.

User Interface Tutorial

General User Interface

Our modern graphical user interface displays all your information in an organised and distinguishable manner, making multitasking more efficient.


Annotated Ui

Component Description
Menu Bar For navigation to File or Help.
Command Box Where the command inputs are typed in.
Results Display Displays notifications for errors or successful commands.
Contact List Shows the contact list based on requested filters.
Event List Shows the event list based on requested filters.
Todo List Shows the todo list based on requested filters.

Contact Card

Annotated Contact Card

Each contact card will reflect (from top to bottom), the contact’s name, tag(s), phone number, address, email and linked event

Event Card

Annotated Event Card

Each event card will reflect (from top to bottom), the event’s name with alias, event description, start and end time.

Todo card

Annotated Todo Card

Each todo card will reflect (from top to bottom), the todo’s name, todo description, linked contact involved and completion status.

Features

Introduction to Prefixes

Prefix Constraint(s)
n/ (Name) Alphanumeric characters, spaces and slashes(/) only. Cannot be blank or start with a slash.
p/ (Phone) Numbers only, at least 3 digits.
e/ (Email) Must follow format: local-part@domain. Local-part: Alphanumeric characters and +, _, ., - (not at start/end). Domain: period-separated labels starting/ending with alphanumeric characters, last label at least 2 consecutive alphanumeric characters .
a/ (Address) Any value; cannot be blank.
t/ (Tag) Alphanumeric characters only, minimum 1 character.
en/ (Event Name) 1-50 chars; letters, numbers, spaces, apostrophes (‘), hyphens (-), ampersands (&), commas (,); trimmed.
ea/ (Event Alias) 1-20 chars; alphanumeric characters, hyphens (-), underscores (_); cannot be blank.
st/, et/ (DateTime) Format: yyyy-MM-dd HH:mm (e.g., 2025-09-19 19:30). Must be valid date and time.
d/ (Event Desc) 1-50 chars (including special characters like slashes); must be non-empty after trimming whitespace.
tn/ (Todo Name) 1-50 chars; letters, numbers, spaces, apostrophes (‘), hyphens (-), ampersands (&), commas (,), slashes (/); trimmed.
td/ (Todo Desc) 1-50 chars (including special characters like slashes); must be non-empty after trimming whitespace.
INDEX Positive integer, non-zero (used for selecting list items).

:information_source: Notes about the command format:

  • All fields will be automatically trimmed (no spacing before or after each parameter) when input inside the command.

  • Words in UPPER_CASE are the parameters to be supplied by the user.
    e.g. in add-contact n/NAME, NAME is a parameter which can be used as add n/John Doe.

  • Items in square brackets are optional.
    e.g n/NAME [t/TAG] can be used as n/John Doe t/friend or as n/John Doe.

  • Items with <blank> means that an empty field (i.e. “ “) can be used to define nothing for supported commands

  • Items with …​ after them can be used multiple times including zero times.
    e.g. [t/TAG]…​ can be used as   (i.e. 0 times), t/friend, t/friend t/family etc.

  • Parameters can be in any order.
    e.g. if the command specifies n/NAME p/PHONE_NUMBER, p/PHONE_NUMBER n/NAME is also acceptable.

  • Extraneous parameters for the commands help, exit and clear will be ignored.
    e.g. if the command specifies help 123, it will be interpreted as help.

  • If you are using a PDF version of this document, be careful when copying and pasting commands that span multiple lines as space characters surrounding line-breaks may be omitted when copied over to the application.

Viewing help : help

Shows a message explaining how to access the help page.

Help message window

Format: help

Contacts

❗Contact names must be unique (case-insensitive). Adding a contact whose name matches an existing one—ignoring letter case—will result in an error.

Adding a person: add-contact

Adds a person to the address book. A person is uniquely identified only by their name in OverBooked; that is, 2 contacts are considered different people as long as their names are different in a case-insensitive comparison.

The command will remove any filters currently in the contact list after execution.

Format: add-contact n/NAME p/PHONE_NUMBER e/EMAIL a/ADDRESS [t/TAG]…​

:bulb: Tip: A person can have any number of tags (including 0) Tags are case-insensitive, meaning t/EMERGENCY and t/emergency will return only the first tag mentioned.

Examples:

  • add-contact n/John Doe p/98765432 e/johnd@example.com a/John street, block 123, #01-01
  • add-contact n/Betsy Crowe t/friend e/betsycrowe@example.com a/Yishun block 53 p/1234567 t/manager

Listing all persons : list-contacts

Shows a list of all persons in the address book. This removes any filters currently in the contact list.

Format: list-contacts

Editing a person : edit-contact

Edits an existing person in the address book. This removes any filters currently in the contact list.

Format: edit-contact INDEX [n/NAME] [p/PHONE] [e/EMAIL] [a/ADDRESS] [t/TAG]…​

  • Edits the person at the specified INDEX.
  • The index refers to the index number shown in the displayed person list.
  • The index must be a positive integer 1, 2, 3, …​
  • At least one of the optional fields must be provided.
  • Existing values will be updated to the input values.
  • When editing tags, the existing tags of the person will be removed i.e adding of tags is not cumulative.
  • Tags are case-insensitive, meaning t/EMERGENCY and t/emergency will return only the first tag mentioned
  • You can remove all the person’s tags by typing t/ without specifying any tags after it.

Examples:

  • edit-contact 1 p/91234567 e/johndoe@example.com Edits the phone number and email address of the 1st person to be 91234567 and johndoe@example.com respectively.
  • edit-contact 2 n/Betsy Crower t/ Edits the name of the 2nd person to be Betsy Crower and clears all existing tags.

Finding persons by name: find-contacts

Finds persons whose names contain any of the given keywords.

Format: find-contacts n/KEYWORD [MORE_KEYWORDS]

  • The search is case-insensitive. e.g hans will match Hans
  • The order of the keywords does not matter. e.g. Hans Bo will match Bo Hans
  • Only the name is searched.
  • Only full words will be matched e.g. Han will not match Hans
  • Persons matching at least one keyword will be returned (i.e. OR search). e.g. Hans Bo will return Hans Gruber, Bo Yang
:bulb: Tip: list-contacts can be used to remove the filter. add-contact and edit-contact will also remove the filter after its execution.

Examples:

  • find-contacts n/John returns john and John Doe
  • find-contacts n/alex david returns Alex Yeoh, David Li

Deleting a person : delete-contact

Deletes the specified person from the address book.

Format: delete-contact INDEX

  • Deletes the person at the specified INDEX.
  • The index refers to the index number shown in the displayed person list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • list-contacts followed by delete-contact 2 deletes the 2nd person in the address book.
  • find-contacts n/Betsy followed by delete-contact 1 deletes the 1st person in the results of the find-contacts command.

Events

❗Each event cannot have the same event alias (case-insensitive)

Adding an event: add-event

Adds an event to the address book. An event is uniquely identified only by its alias in OverBooked; that is, 2 events are considered different as long as their aliases are different in a case-insensitive comparison.

The command will remove any filters currently in the event list after execution.

Format: add-event en/EVENT_NAME ea/EVENT_ALIAS st/START_DATETIME et/END_DATETIME d/DESCRIPTION

Examples:

  • add-event en/Taylor Swift Concert ea/TSC2025 st/2025-09-19 19:30 et/2025-09-19 23:30 d/Taylor's Swift Eras tour

Links a given contact (by index based on displayed list) to an event (by alias).

❗Each contact can only link to one specific event.

❗Linking an event to a contact that already has an event linked, will just update and replace it.

Format: link-event INDEX [MORE_INDEXES] ea/EVENT_ALIAS

  • The index refers to the index number shown in the displayed person list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • link-event 1 ea/TSC2025
  • link-event 1 2 ea/OL2028

Unlink any given contact (by index based on displayed list) from an event.

❗Unlinking an event from an unlinked person, will show that he/she is unlinked again.

Format: unlink-event INDEX [MORE_INDEXES]

  • The index refers to the index number shown in the displayed person list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • unlink-event 1 2

Listing all events : list-events

Shows a list of all events in the address book. This removes any filters currently in the event list.

Format: list-events

Editing an event: edit-event

Edits an existing event in the address book. This removes any filters currently in the event list.

:bulb: Tip: An EventAlias cannot be edited in order to enforce uniqueness. The event alias field included in the field is to identify which specific event you want to amend.

Format: edit-event ea/EVENT_ALIAS [en/EVENT_NAME] [st/START_DATETIME] [et/END_DATETIME] [d/DESCRIPTION]

  • Edits the event by the specified EVENT_ALIAS.
  • At least one of the optional fields must be provided.
  • Existing values will be updated to the input values.

Example:

  • edit-event ea/TSC2025 en/Taylor Swift’s Concert st/2025-09-19 18:30 Edits the event name and start datetime of the event with alias TSC2025 to be Taylor Swift’s Concert and 2025-09-19 18:30 respectively.

Finding events by alias: find-event

Finds events whose aliases start with any of the given keywords.

Format: find-event ea/KEYWORD [MORE_KEYWORDS]

The search is case-insensitive. e.g tsc will match TSC The order of the keywords does not matter. Only the alias is searched. Events whose aliases start with at least one keyword will be returned (i.e. OR search). e.g. tsc will return TSC2024, TSC2025. In short, the search does not require the full alias to match the searched prefix.

:bulb: Tip: list-events can be used to remove the filter. add-event and edit-event will also remove the filter after its execution.

Examples:

  • find-event ea/TSC returns TSC2024 and TSC2025
  • find-event ea/BTS BP returns BTS2025 and BP2025

Deleting an event: delete-event

  • Deletes an event from the address book by the event alias.

Format: delete-event ea/EVENT_ALIAS

Examples:

  • delete-event ea/TSC2025 deletes the event with alias TSC2025.

Finding a contact by event: find-by-event

Finds and displays all contacts that are linked to a specific event.

Format: find-by-event ea/EVENT_ALIAS

:bulb: Tip: list-contacts can be used to remove the filter. add-contact and edit-contact will also remove the filter after its execution.

Examples:

  • find-by-event ea/TSC2025

Todos

❗Each Todo cannot have the same todo name and description (both case-insensitive)

Adding a todo: add-todo

Adds a todo to the address book. A todo is uniquely identified only by its todo name and todo description in OverBooked; that is, 2 todos are considered different todos as long as the todo names or todo descriptions are different in a case-insensitive comparison.

Format: add-todo tn/TODO_NAME td/TODO_DESCRIPTION [n/NAME]

  • Only existing contacts can be linked to a todo (i.e. an existing contact must have the specified contact name).

Examples:

  • add-todo tn/Call Alex td/Find out event requirements n/Alex Yeoh

Editing a todo: edit-todo

Edits an existing todo in the address book.

Format: edit-todo INDEX [tn/TODO_NAME] [td/TODO_DESCRIPTION] [n/NAME]

  • Edits the todo at the specified INDEX.
  • The index refers to the index number shown in the displayed todo list.
  • The index must be a positive integer 1, 2, 3, …​
  • At least one of the optional fields must be provided.
  • Existing values will be updated to the input values.
  • You can unlink the person from the todo by typing n/ without specifying any name after it
  • Only existing contacts can be linked to a todo (i.e. an existing contact must have the specified contact name).

Examples:

  • edit-todo 1 tn/Call John n/John Doe
  • edit-todo 1 n/<blank> unlinks the person from the first todo task.

Deleting a todo: delete-todo

Deletes a todo from the address book.

Format: delete-todo INDEX

  • Deletes the todo at the specified INDEX.
  • The index refers to the index number shown in the displayed todo list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • delete-todo 1

Listing all todos : list-todos

Shows a list of all todos in the address book.

Format: list-todos

Marking a todo as completed : mark-todo

Marks the specified todo as completed.

Format: mark-todo INDEX

  • Marks the todo at the specified INDEX as completed.
  • The index refers to the index number shown in the displayed todo list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • list-todos followed by mark-todo 2 marks the 2nd todo in the address book as completed.

Marking a todo as incomplete : unmark-todo

Marks the specified todo as incomplete.

Format: unmark-todo INDEX

  • Marks the todo at the specified INDEX as incomplete.
  • The index refers to the index number shown in the displayed todo list.
  • The index must be a positive integer 1, 2, 3, …​

Examples:

  • list-todos followed by unmark-todo 2 marks the 2nd todo in the address book as incomplete.

Miscellaneous

Clearing all entries : clear

Clears all entries from the address book.

Format: clear

Exiting the program : exit

Exits the program.

Format: exit

Saving the data

OverBooked data is saved in the hard disk automatically after any command that changes the data. There is no need to save manually.

Editing the data file

OverBooked data is saved automatically as a JSON file [JAR file location]/data/addressbook.json. Advanced users are welcome to update data directly by editing that data file.

:exclamation: Caution: If the data file becomes an invalid json file or fields no longer fall within given restrictions after user edits, OverBooked will create a new empty file to replace it. In some cases, database consistency may not be guaranteed. Hence, it is recommended to make a backup of the file before editing it.
Furthermore, certain edits can cause the OverBooked to behave in unexpected ways (e.g., if a value entered is outside of the acceptable range). Therefore, edit the data file only if you are confident that you can update it correctly.

FAQ

Q: How do I transfer my data to another Computer?
A: Install the app in the other computer and overwrite the empty data file it creates with the file that contains the data of your previous OverBooked home folder.

Known issues

  1. When using multiple screens, if you move the application to a secondary screen, and later switch to using only the primary screen, the GUI will open off-screen. The remedy is to delete the preferences.json file created by the application before running the application again.
  2. If you minimize the Help Window and then run the help command (or use the Help menu, or the keyboard shortcut F1) again, the original Help Window will remain minimized, and no new Help Window will appear. The remedy is to manually restore the minimized Help Window.

Command summary

Action Format, Examples  
👤 Contacts    
add-contact add-contact n/NAME p/PHONE_NUMBER e/EMAIL a/ADDRESS [t/TAG]…​
e.g., add-contact n/James Ho p/22224444 e/jamesho@example.com a/123, Clementi Rd, 1234665 t/logistics t/colleague 		 
edit-contact edit-contact INDEX [n/NAME] [p/PHONE] [e/EMAIL] [a/ADDRESS] [t/TAG]…​
e.g. edit-contact 2 n/James Lee e/jameslee@example.com 		 
delete-contact delete-contact INDEX
e.g. delete-contact 3 		 
find-contacts find-contacts n/KEYWORD [MORE_KEYWORDS]
e.g. find-contacts n/James Jake 		 
list-contacts list-contacts  
find-by-event find-by-event ea/EVENT_ALIAS
e.g. find-by-event ea/TSC2025 		 
🎫 Events    
add-event add-event en/EVENT_NAME ea/EVENT_ALIAS st/START_DATETIME et/END_DATETIME d/DESCRIPTION
e.g. add-event en/Taylor Swift Concert ea/TSC2025 st/2025-09-19 19:30 et/2025-09-19 23:30 d/World Tour 		 
edit-event edit-event ea/EVENT_ALIAS [en/EVENT_NAME] [st/START_DATETIME] [et/END_DATETIME] [d/DESCRIPTION]
e.g. edit-event ea/TSC2025 en/Taylor Swift’s Concert st/2025-09-19 18:30 		 
delete-event delete-event ea/EVENT_ALIAS
e.g. delete-event ea/TSC2025 		 
list-events list-events  
find-event find-event ea/KEYWORD [MORE_KEYWORDS]
e.g. find-event ea/TSC 		 
link-event link-event INDEX [MORE_INDEXES] ea/EVENT_ALIAS
e.g. link-event 1 2 ea/TSC2025 		 
unlink-event unlink-event INDEX [MORE_INDEXES]
e.g. unlink-event 1 2 		 
📝 Todos    
add-todo add-todo tn/TODO_NAME td/TODO_DESCRIPTION [n/NAME]
e.g. add-todo tn/Call Alex td/Confirm event n/Alex Yeoh 		 
edit-todo edit-todo INDEX [tn/TODO_NAME] [td/TODO_DESCRIPTION] [n/NAME]
e.g. edit-todo 1 tn/Call John td/Confirm appointment with John n/John Doe 		 
delete-todo delete-todo INDEX
e.g.delete-todo 1 		 
list-todos list-todos  
mark-todo mark-todo INDEX
e.g.mark-todo 1 		 
unmark-todo unmark-todo INDEX
e.g.unmark-todo 1 		 
💻 System    
help help  
clear clear  
exit exit  

Notes:

  • Multiple entries permitted for tags ([t/TAG]…​).
  • Optional prefixes can be left blank only where allowed (e.g., n/<blank> for unlinking a name from a todo).
  • For all string fields, leading/trailing whitespace is trimmed.
  • Date/time values must strictly follow the indicated format.