Yakuake provides a hotkey and a GUI way to rename commandline tabs/sessions.
I'd like to do the same via the command line, so I can script it and use it in an alias. (My goal is that if I use an alias which does an SSH to some server, then the tab is renamed according to this servers name...)
I tried the suggestions shown here Renaming a Konsole session from commandline after ssh so far no luck.
Since KDE4, one should use qdbus to control KDE apps (instead of deprecated and deleted DCOP).
For example, to change a title of the first session one may use:
qdbus org.kde.yakuake /Sessions/1 org.kde.konsole.Session.setTitle 1 "New title"
To explore available interfaces, methods and properties one may use qdbusviewer.
As a homework try to get a list of active sessions (before you going to change smth).