core/homeassistant/components/stream/services.yaml

record:
  description: Make a .mp4 recording from a provided stream.
  fields:
    stream_source:
      description: The input source for the stream.
      example: "rtsp://my.stream.feed:554"
    filename:
      description: The file name string.
      example: "/tmp/my_stream.mp4"
    duration:
      description: "Target recording length (in seconds). Default: 30"
      example: 30
    lookback:
      description: "Target lookback period (in seconds) to include in addition to duration. Only available if there is currently an active HLS stream for stream_source. Default: 0"
      example: 5