Hint
This property allows you to define the text shown in the window that pops up when the mouse pointer is placed on the Split-Pane control.
 
Example - Define a split pane with hint text
screen section.
...
  03 screen-1-sp-1 Split-pane
     line 4.0
     column 41.5
     size 2.9 cells 
     lines 39.7 cells 
     hint "Split-pane hint"
     .
...