{
  "context": "This criteria evaluates how well the engineer uses the aiortc package's MediaPlayer class for cross-platform hardware device capture. The focus is on proper usage of MediaPlayer's device format parameter, correct platform-specific device path construction, and appropriate integration with aiortc's media streaming infrastructure.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "MediaPlayer instantiation",
      "description": "Uses MediaPlayer from aiortc.contrib.media to create audio and video device players with the correct format parameter (e.g., MediaPlayer(device_path, format='v4l2') for Linux video).",
      "max_score": 25
    },
    {
      "name": "Platform-specific formats",
      "description": "Correctly identifies and uses the appropriate format parameter for each platform: 'v4l2' for Linux video, 'alsa' or 'pulse' for Linux audio, 'avfoundation' for macOS audio/video, and 'dshow' for Windows audio/video.",
      "max_score": 20
    },
    {
      "name": "Device path construction",
      "description": "Constructs proper device paths that match the expected format for each platform's backend (e.g., '/dev/video0' for v4l2, numeric indices or device names for avfoundation/dshow).",
      "max_score": 15
    },
    {
      "name": "Track access",
      "description": "Correctly accesses audio and video tracks from the MediaPlayer instance using the 'audio' and 'video' properties provided by MediaPlayer.",
      "max_score": 15
    },
    {
      "name": "Platform detection",
      "description": "Implements platform detection using Python's sys.platform or platform module to determine the current operating system and select the appropriate device backend.",
      "max_score": 10
    },
    {
      "name": "Options parameter",
      "description": "Uses MediaPlayer's options parameter when needed to pass additional format-specific options (e.g., frame rate, resolution, or audio sample rate).",
      "max_score": 10
    },
    {
      "name": "Error handling",
      "description": "Handles exceptions that may be raised by MediaPlayer when devices are unavailable or invalid, providing meaningful error messages to the user.",
      "max_score": 5
    }
  ]
}