Scheduling

function broadcastEntityCount() {
    var server = plugin.getServer();
    var entityCount = 0;
    var worlds = server.getWorlds();

    for (var i = 0; i < worlds.size(); i++) {
        var world = worlds.get(i);
        entityCount += world.getEntities().size();
    }

    server.broadcastMessage("Total entities: " + entityCount);
}

// Register the schedule to run every 10 seconds (200 ticks)
registerSchedule(0, 200, this, "broadcastEntityCount");

Or:

// Register the schedule to run every 10 seconds (200 ticks)
registerSchedule(0, 200, {
        handler: function() {
            var server = plugin.getServer();
            var entityCount = 0;
            var worlds = server.getWorlds();
            
            for (var i = 0; i < worlds.size(); i++) {
                var world = worlds.get(i);
                entityCount += world.getEntities().size();
            }
            
            server.broadcastMessage("Total entities: " + entityCount);
    }}, "handler");

This is not a complete documentation on scheduling