Drawing line in Script-Fu

[Strzegol]

Hello. Still another newbie question. Why this script don't work? (GIMP 2.99 but this is so basic stuff that this should don't matter)

EDIT: I checked documentations for hours and also mined examples shipped with GIMP but there are no examples that use gimp-paintbrush-default and oddly I don't found anything in documentation about creation of scripts that draw something on existing images despite this kind of scripts seems to be most common)

EDIT: It should draw line from cornet to pixel at x=100 y=100 using current brush.

Code:

(define (script-fu-linedraw drawable orientation)
    (gimp-paintbrush-default drawable 2 #(0 0 100 100))

)

(script-fu-register
    "script-fu-linedraw"
    "Linedraw"
    "Try draw a line in GIMP"
    "Strzegol"
    "copyright 2023 Strzegol"
    "September 12,2023"
    ""
    SF-DRAWABLE "Drawable" 0

)
(script-fu-menu-register "script-fu-linedraw"
    "<Image>/Tools")

Second stuff: Why refreshing scripts remove them from menu?