<div id="chart"></div>
<script>
$("#chart").kendoChart({
  valueAxis: [{
    notes: {
      data: [{
        value: 3.5,
        text: "Value at 3.5"
      }]
    }
  }],
  series: [
    { data: [1, 2, 3, 4, 5] }
  ]
});
</script>