{
  "context": "This evaluation assesses how well the engineer uses better-scroll's real-time position tracking capabilities, particularly the RAF-based animation system and scroll event mechanisms, to build a position tracker with analytics.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "BScroll instantiation",
      "description": "Creates a BScroll instance using the correct constructor pattern with a wrapper element",
      "max_score": 10
    },
    {
      "name": "probeType configuration",
      "description": "Configures probeType option to 3 to enable real-time scroll position tracking during animations via RequestAnimationFrame",
      "max_score": 25
    },
    {
      "name": "scroll event listener",
      "description": "Registers a listener for the 'scroll' event to capture position updates during scrolling",
      "max_score": 20
    },
    {
      "name": "Position access",
      "description": "Accesses the scroll instance's x and y properties to get current scroll position",
      "max_score": 15
    },
    {
      "name": "Position data tracking",
      "description": "Collects and stores position data (x, y, timestamp) in the scroll event handler",
      "max_score": 15
    },
    {
      "name": "Analytics calculation",
      "description": "Implements distance calculation and other analytics based on collected position data",
      "max_score": 10
    },
    {
      "name": "Resource cleanup",
      "description": "Calls destroy() method on the BScroll instance to properly clean up event listeners and resources",
      "max_score": 5
    }
  ]
}