{
  "session_id": "session_data_20260404_174729",
  "total_duration_s": 1087.3,
  "n_input_spans": 65,
  "session_goal": "Wind blue bobbins, set up sewing machine, sew blue striped and patterned fabrics with teal and trim, then iron and trim the blue fabric.",
  "sub_goals": [
    {
      "sub_goal_id": 1,
      "start_time": 0.0,
      "end_time": 130.0,
      "description": "Wind blue bobbins and thread the sewing machine with bobbin and upper thread.",
      "episodes": [
        {
          "episode_id": 1,
          "start_time": 0.0,
          "end_time": 52.0,
          "description": "Wind thread onto two blue bobbins using sewing machine bobbin winder.",
          "span_indices": [
            0,
            1,
            2,
            3
          ]
        },
        {
          "episode_id": 2,
          "start_time": 52.0,
          "end_time": 130.0,
          "description": "Insert bobbin, thread upper thread, and adjust sewing machine tension.",
          "span_indices": [
            4,
            5,
            6,
            7,
            8,
            9,
            10
          ]
        }
      ]
    },
    {
      "sub_goal_id": 2,
      "start_time": 130.0,
      "end_time": 581.0,
      "description": "Sew blue striped fabric pieces into strips and cut excess threads.",
      "episodes": [
        {
          "episode_id": 3,
          "start_time": 130.0,
          "end_time": 216.0,
          "description": "Align and sew three sets of blue striped fabric pieces, then cut thread.",
          "span_indices": [
            11,
            12,
            13,
            14,
            15,
            16,
            17
          ]
        },
        {
          "episode_id": 4,
          "start_time": 216.0,
          "end_time": 300.0,
          "description": "Align and sew a long continuous seam of blue striped fabric, then trim.",
          "span_indices": [
            18,
            19,
            20,
            21
          ]
        },
        {
          "episode_id": 5,
          "start_time": 300.0,
          "end_time": 581.0,
          "description": "Sew combined blue striped and light blue fabric strips, then cut and remove.",
          "span_indices": [
            22,
            23,
            24,
            25,
            26
          ]
        }
      ]
    },
    {
      "sub_goal_id": 3,
      "start_time": 581.0,
      "end_time": 934.0,
      "description": "Arrange blue patterned and teal fabrics, sew them, and attach blue trim.",
      "episodes": [
        {
          "episode_id": 6,
          "start_time": 581.0,
          "end_time": 643.0,
          "description": "Arrange sewn blue strips, blue patterned fabric, and teal fabric on worktable.",
          "span_indices": [
            27,
            28,
            29,
            30,
            31,
            32,
            33
          ]
        },
        {
          "episode_id": 7,
          "start_time": 643.0,
          "end_time": 738.0,
          "description": "Sew blue patterned fabric and attach solid teal fabric with sewing machine.",
          "span_indices": [
            34,
            35,
            36,
            37,
            38,
            39,
            40
          ]
        },
        {
          "episode_id": 8,
          "start_time": 738.0,
          "end_time": 799.0,
          "description": "Reposition fabric and sew blue trim onto fabric edge.",
          "span_indices": [
            41,
            42,
            43,
            44
          ]
        },
        {
          "episode_id": 9,
          "start_time": 799.0,
          "end_time": 900.0,
          "description": "Sew teal section, additional seams, and blue trim, then inspect fabric.",
          "span_indices": [
            45,
            46,
            47,
            48,
            49,
            50,
            51,
            52,
            53
          ]
        },
        {
          "episode_id": 10,
          "start_time": 900.0,
          "end_time": 934.0,
          "description": "Sew another blue patterned fabric piece, cut thread, and lift fabric.",
          "span_indices": [
            54,
            55,
            56
          ]
        }
      ]
    },
    {
      "sub_goal_id": 4,
      "start_time": 934.0,
      "end_time": 1087.3,
      "description": "Iron blue fabric with electric iron, then measure and trim with scissors.",
      "episodes": [
        {
          "episode_id": 11,
          "start_time": 934.0,
          "end_time": 1019.0,
          "description": "Unfold blue fabric on mat, iron with electric iron, and place iron back.",
          "span_indices": [
            57,
            58,
            59,
            60
          ]
        },
        {
          "episode_id": 12,
          "start_time": 1019.0,
          "end_time": 1087.3,
          "description": "Measure and trim blue fabric with scissors, then position under sewing machine.",
          "span_indices": [
            61,
            62,
            63,
            64
          ]
        }
      ]
    }
  ]
}