diff --git a/docs/diagrams/CheckCommand.puml b/docs/diagrams/CheckCommand.puml
new file mode 100644
index 00000000000..336b08b33f5
--- /dev/null
+++ b/docs/diagrams/CheckCommand.puml
@@ -0,0 +1,76 @@
+@startuml
+!include style.puml
+skinparam ArrowFontStyle plain
+
+box Logic LOGIC_COLOR_T1
+participant ":LogicManager" as LogicManager LOGIC_COLOR
+participant ":AddressBookParser" as AddressBookParser LOGIC_COLOR
+participant ":CheckCommandParser" as CheckCommandParser LOGIC_COLOR
+participant "c:CheckCommand" as CheckCommand LOGIC_COLOR
+participant "r:CommandResult" as CommandResult LOGIC_COLOR
+end box
+
+box Model MODEL_COLOR_T1
+participant "m:Model" as Model MODEL_COLOR
+end box
+
+[-> LogicManager : execute("check T0123456A")
+activate LogicManager
+
+LogicManager -> AddressBookParser : parseCommand("check T0123456A")
+activate AddressBookParser
+
+create CheckCommandParser
+AddressBookParser -> CheckCommandParser
+activate CheckCommandParser
+
+CheckCommandParser --> AddressBookParser
+deactivate CheckCommandParser
+
+AddressBookParser -> CheckCommandParser : parse("T0123456A")
+activate CheckCommandParser
+
+create CheckCommand
+CheckCommandParser -> CheckCommand
+activate CheckCommand
+
+CheckCommand --> CheckCommandParser :
+deactivate CheckCommand
+
+CheckCommandParser --> AddressBookParser : c
+deactivate CheckCommandParser
+'Hidden arrow to position the destroy marker below the end of the activation bar.
+CheckCommandParser -[hidden]-> AddressBookParser
+destroy CheckCommandParser
+
+AddressBookParser --> LogicManager : c
+deactivate AddressBookParser
+
+LogicManager -> CheckCommand : execute(m)
+activate CheckCommand
+
+CheckCommand -> Model : updateFilteredPersonList(new NricContainsKeywordsPredicate("T0123456A"));
+activate Model
+
+Model --> CheckCommand : getFilteredPersonList()
+deactivate Model
+
+CheckCommand -> Model : updateFilteredVisitList(new VisitContainsNricPredicate("T0123456A"));
+activate Model
+
+Model --> CheckCommand : getFilteredVisitList()
+deactivate Model
+
+create CommandResult
+CheckCommand -> CommandResult
+activate CommandResult
+
+CommandResult --> CheckCommand
+deactivate CommandResult
+
+CheckCommand --> LogicManager : r
+deactivate CheckCommand
+
+[<--LogicManager
+deactivate LogicManager
+@enduml
diff --git a/docs/diagrams/ReadCommand.puml b/docs/diagrams/ReadCommand.puml
index c4262e3a335..0b937675baa 100644
--- a/docs/diagrams/ReadCommand.puml
+++ b/docs/diagrams/ReadCommand.puml
@@ -7,7 +7,7 @@ participant ":LogicManager" as LogicManager LOGIC_COLOR
 participant ":AddressBookParser" as AddressBookParser LOGIC_COLOR
 participant ":ReadCommandParser" as ReadCommandParser LOGIC_COLOR
 participant "r:ReadCommand" as ReadCommand LOGIC_COLOR
-participant "r:CommandResult" as CommandResult LOGIC_COLOR
+participant "c:CommandResult" as CommandResult LOGIC_COLOR
 end box
 
 box Model MODEL_COLOR_T1
@@ -49,10 +49,10 @@ deactivate AddressBookParser
 LogicManager -> ReadCommand : execute(m)
 activate ReadCommand
 
-ReadCommand -> Model
+ReadCommand -> Model : updateFilteredPersonList(new NricContainsKeywordsPredicate("T0123456A"));
 activate Model
 
-Model --> ReadCommand
+Model --> ReadCommand : getFilteredPersonList()
 deactivate Model
 
 create CommandResult
@@ -62,7 +62,7 @@ activate CommandResult
 CommandResult --> ReadCommand
 deactivate CommandResult
 
-ReadCommand --> LogicManager :
+ReadCommand --> LogicManager : c
 deactivate ReadCommand
 
 [<--LogicManager
diff --git a/docs/images/CheckCommand.png b/docs/images/CheckCommand.png
new file mode 100644
index 00000000000..6669b08c9ce
Binary files /dev/null and b/docs/images/CheckCommand.png differ
diff --git a/docs/images/ReadCommand.png b/docs/images/ReadCommand.png
index 110426eb2a8..9756e0ea3b6 100644
Binary files a/docs/images/ReadCommand.png and b/docs/images/ReadCommand.png differ