{
  "session_id": "session_data_20260406_131831",
  "total_duration_s": 572.4,
  "n_input_spans": 23,
  "session_goal": "Sew a thin green fabric strip onto large green patterned fabric, hem it, cut and arrange green and blue fabrics, and handle a mobile phone.",
  "sub_goals": [
    {
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      "start_time": 0.0,
      "end_time": 231.0,
      "description": "Sew thin green fabric strip onto large green patterned fabric and hem the edge with sewing machine.",
      "episodes": [
        {
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          "end_time": 182.0,
          "description": "Sew thin green fabric strip onto large green patterned fabric with sewing machine.",
          "span_indices": [
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            1,
            2
          ]
        },
        {
          "episode_id": 2,
          "start_time": 182.0,
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          "description": "Fold edge and sew hem on large green patterned fabric with sewing machine.",
          "span_indices": [
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            4
          ]
        }
      ]
    },
    {
      "sub_goal_id": 2,
      "start_time": 231.0,
      "end_time": 377.4,
      "description": "Cut and arrange green and blue fabrics with scissors, and handle mobile phone.",
      "episodes": [
        {
          "episode_id": 1,
          "start_time": 231.0,
          "end_time": 300.0,
          "description": "Position blue fabric, cut green fabric, fold, trim edges, and arrange pieces on worktable.",
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            6,
            7,
            8,
            9
          ]
        },
        {
          "episode_id": 2,
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          "end_time": 344.0,
          "description": "Arrange green and blue fabrics on sewing table and cut green fabric with scissors.",
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            11,
            12,
            13,
            14,
            15,
            16,
            17
          ]
        },
        {
          "episode_id": 3,
          "start_time": 344.0,
          "end_time": 377.4,
          "description": "Pick up mobile phone from bed, place on sewing table, arrange green fabric, and cut with scissors.",
          "span_indices": [
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            19,
            20,
            21,
            22
          ]
        }
      ]
    }
  ]
}