You're welcome.
@ronjonp
Yeah, you are right and I am honestly aware of that but the OP asks for something very simple faraway enough from the DXF group 3.
Brave fox by the way.
No its not.
(defun c:replace1 (/ text sel int)
(setq text "this is a description text")
(if (setq sel (ssget "_:L" '((0 . "MTEXT,TEXT"))))
(repeat (setq int (sslength sel))
(entmod (append (entget (ssname sel (setq int (1- int))))
(list (cons 1 text))
)
)
)
)
(princ)
)