As we have spoke about before there is no way from the GUI to customize the automail message that is sent. You will need to create workflow that will create a custom email for you. I have a an example of what you would need to do to create this custom email message. This would be added to the Bug_AfterPost section of the workflow. It will create and send an email that contains the BugID, Severity, Domain, and Project of the bug assigned to the user.

You will need to test this in your environment but it should show you what you will need to do to create the email message that you are looking for.

Sub Bug_AfterPost
On Error Resume Next
Dim strSubject, strComment, intBugID, strTo, strCC
If Bug_Fields.Field(''BG_RESPONSIBLE'').IsModified Then 'checks to see if this field is modified
'strSubject holds the subject for the email
strSubject = ''Defect ID '' & Bug_Fields.Field(''BG_BUG_ID'').Value & '' has been assigned to you.''
'strMessage holds the body of the email message
strMessage = ''Defect ID: '' & Bug_Fields.Field(''BG_BUG_ID'').Value & vbCrLf & ''Severity: '' & Bug_Fields.Field(''BG_SEVERITY'').Value & vbCrLf & ''Domain: '' & TDConnection.DomainName & vbCrLf & ''Project: '' & TDConnection.ProjectName
'strTo either the ALM user name or can be an email address ex. jon.schwartz@FTR.com addresses can be seperated by a comma or semi-colon
strTo = Bug_Fields.Field(''BG_RESPONSIBLE'').Value
'Gets users email address from ALM username stored in strTO variable
'strTo = TDConnection.Customization.Users.User(strTo).Email

'Here is where the email is actually sent... https://admhelp.microfocus.com/alm/en/12.53/api_refs/ota/webframe.html for more information
TDConnection.SendMail strTo, '''', strSubject, strMessage, NULL, ''TEXT''
End If
On Error GoTo 0
End Sub