Depending on the goal, you might be able to use a data table and an existing platform and just label the points with another column. One of the column attributes is Use For Marker.
UseForMarker circled in red.
But to do what you describe, the graphics script needs to have a loop that gets labels (and color and marker data) from a container of some sort. The container can be a list, a data table, or an associative array. If you add a label to the container, you can send the <<inval message to the graph to make it redraw. When it redraws, the graphics script will process all the labels from the container.
list = {{"aaa", 10, 10, "red"}};
New Window( "Example",
gb=Graph Box(
For( i = 1, i <= N Items( list ), i += 1,
thisLabel = list[i];
Text Color( thisLabel[4] );
Text( Center Justified, {thisLabel[2], thisLabel[3]}, thisLabel[1] );
)
)
);
wait(1);
list[2] = {"bbb",20,20,"blue"};
gb<<inval;
wait(1);
list[3] = {"ccc",30,30,"green"};
gb<<inval;
Three seconds later...
Craige