participant USER as U
participant APPLICATION\n(your code) as A
participant PERMISSION\nSEVER as PS
participant USER\nEMAIL as E

Note over U: Request
U -> A   : abc@example.com
A -> PS  : abc@example.com
Note over PS: Creates Token
PS -> E  : 12345678
PS --> A :
A --> U  : ""Check Email""

Note over U: Confirm
U -> A   : abc@example.com\n12345678
A -> PS  : abc@example.com\n12345678
Note over PS: Confirms Token
PS --> A :
Note over A: Optional\nApplication\nAccounts
A --> U  : Session Cookie\n(for example)