Hi
You could use the MultiTargetPath to do this.
I think something like this should work
// Disable the automatic path recalculation
ai.canSearch = false;
var path = MultiTargetPath.Construct(ai.position, targetPointsArray, null, null);
ai.SetPath(path);
Note that since you have to set ai.canSearch=false, the agent will no longer recalculate its path by itself, your script is responsible for that now.