diff --git a/docs/DeveloperGuide.md b/docs/DeveloperGuide.md
index b0200f3fde3..b7ca215e7a5 100644
--- a/docs/DeveloperGuide.md
+++ b/docs/DeveloperGuide.md
@@ -176,7 +176,7 @@ Step 1. The user launches the application for the first time. The `VersionedAddr
 
 <puml src="diagrams/UndoRedoState0.puml" alt="UndoRedoState0" />
 
-Step 2. The user executes `delete 5` command to delete the 5th person in the address book. The `delete` command calls `Model#commitAddressBook()`, causing the modified state of the address book after the `delete 5` command executes to be saved in the `addressBookStateList`, and the `currentStatePointer` is shifted to the newly inserted address book state.
+Step 2. The user executes `delete T0123456A` command to delete the person in the address book with the unique identification number `T0123456A`. The `delete` command calls `Model#commitAddressBook()`, causing the modified state of the address book after the `delete T0123456A` command executes to be saved in the `addressBookStateList`, and the `currentStatePointer` is shifted to the newly inserted address book state.
 
 <puml src="diagrams/UndoRedoState1.puml" alt="UndoRedoState1" />
 
@@ -481,13 +481,13 @@ testers are expected to do more *exploratory* testing.
 
    1. Prerequisites: List all persons using the `list` command. Multiple persons in the list.
 
-   1. Test case: `delete 1`<br>
-      Expected: First contact is deleted from the list. Details of the deleted contact shown in the status message. Timestamp in the status bar is updated.
+   1. Test case: `delete T0123456A`<br>
+      Expected: The contact with the unique identification number `T0123456A` is deleted from the list. Details of the deleted contact shown in the status message. Timestamp in the status bar is updated.
 
-   1. Test case: `delete 0`<br>
+   1. Test case: `delete T0123A`<br>
       Expected: No person is deleted. Error details shown in the status message. Status bar remains the same.
 
-   1. Other incorrect delete commands to try: `delete`, `delete x`, `...` (where x is larger than the list size)<br>
+   1. Other incorrect delete commands to try: `delete`, `delete x`, `...` (where x is the identification number which does not exist in the list)<br>
       Expected: Similar to previous.
 
 1. _{ more test cases …​ }_
diff --git a/docs/UserGuide.md b/docs/UserGuide.md
index cab9a730a69..6caed7e46c0 100644
--- a/docs/UserGuide.md
+++ b/docs/UserGuide.md
@@ -30,7 +30,7 @@ Clinic Mate is a **desktop** app for managing contacts in a clinic, optimized fo
 
    * `list` : Lists all contacts.
 
-   * `add n/John Doe i/T0123456A ag/12 s/Male a/John street, block 123, #01-01` : Adds a contact named `John Doe` to the Address Book.
+   * `add n/John Doe p/88888888 e/johndoe@mail.com i/T0123456A ag/12 s/Male a/John street, block 123, #01-01` : Adds a contact named `John Doe` to the Address Book.
 
    * `delete T0123456A` : Deletes the contact with the IC 'T0123456A' shown in the current list.
 
@@ -68,12 +68,14 @@ Shows a message explaining how to access the help page.
 
 Format: `help`
 
-
 ### Adding a person: `add`
 
 Adds a person to the address book.
 
-Format: `add n/NAME i/IC_NUMBER ag/AGE s/SEX a/ADDRESS`
+Format: `add n/NAME p/PHONE e/EMAIL i/IC_NUMBER ag/AGE s/SEX a/ADDRESS`
+
+* A person will be uniquely identified by his/her personal identification number.
+* Clinic mate does not allow the same identification number to be twice.
 
 <box type="tip" seamless>
 
@@ -81,7 +83,7 @@ Format: `add n/NAME i/IC_NUMBER ag/AGE s/SEX a/ADDRESS`
 </box>
 
 Examples:
-* `add n/John Doe i/T0123456A ag/12 s/Male a/John street, block 123, #01-01`
+* `add n/John Doe p/88888888 e/johndoe@mail.com i/T0123456A ag/12 s/Male a/John street, block 123, #01-01`
 
 ### Adding a note : `addnote`
 
@@ -172,7 +174,7 @@ _Details coming soon ..._
 
 Action     | Format, Examples
 -----------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------
-**Add**    | `add n/NAME i/IC_NUMBER ag/AGE s/SEX a/ADDRESS` <br> e.g., `add n/John Doe i/T0123456A ag/12 s/Male a/John street, block 123, #01-01`
+**Add**    | `add n/NAME p/PHONE e/EMAIL i/IC_NUMBER ag/AGE s/SEX a/ADDRESS` <br> e.g., `add n/John Doe p/88888888 e/johndoe@mail.com i/T0123456A ag/12 s/Male a/John street, block 123, #01-01`
 **Clear**  | `clear`
 **Delete** | `delete IC_NUMBER`<br> e.g., `delete T0123456A`
 **AddNote**   | `addnote i/IC_NUMBER n/NOTE`<br> e.g., `addnote i/T0123456A n/Patient has diabetes`