LotusScript for IncludeDocLinks in @Mailsend

There's not a direct replacement. If you want to have more control, you go to LotusScript, but boy do you get a LOT more control. Here's what you'll need to do to have the @MailSend duplicated in LotusScript, functionally:

Dim wsCurrent As New NotesUIWorkspace
Dim nsCurrent As New NotesSession
Dim ndbCurrent As NotesDatabase
Dim ndMail As NotesDocument
Dim nrtMailBody As NotesRichTextItem
Dim sMessage As String
Dim sSendTo As String

sSendTo = "First Person/MyGroup/MyCompany"
sMessage = InputBox$("What message:")
Set ndbCurrent = nsCurrent.CurrentDatabase
Set ndMail = ndbCurrent.CreateDocument
ndMail.Form = "Memo"
Set nrtMailBody = ndbCurrent.CreateRichTextItem("Body")
If sMessage <> "" Then
	Call nrtMailBody.AppendText(sMessage)
End If
Call nrtMailBody.AppendDocLink(ndbCurrent, "Link to my Doc")
Call ndMail.Send(False, sSendTo)

The object you put in the AppendDocLink method can be a NotesDatabase (as I used here), and NotesView, or a NotesDocument object.