{
  "_doc": "IMP-#91 u8 — F2 slot_payload axis. Pins step12_slot_payload.json per_zone structural shape (position / template_id / builder / slot_names / list_slot_counts / dict_slot_sub_counts / string_slot_nonempty) for mdx 01-05. Pins SHAPE not literal content — text edits in MDX won't drift this snapshot, but builder swap / slot rename / missing slot / list-cardinality drift will. __empty__ zones have builder=null and zero slots.",
  "01": [
    {
      "position": "top",
      "template_id": "bim_dx_comparison_table",
      "builder": "compare_table_2col",
      "slot_names": ["col_a_label", "col_b_label", "rows", "title"],
      "list_slot_counts": {"rows": 2},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {"col_a_label": true, "col_b_label": true, "title": true}
    },
    {
      "position": "bottom",
      "template_id": "construction_bim_three_usage",
      "builder": "quadrant_flat_slots",
      "slot_names": ["category_1_body", "category_1_label", "category_2_body", "category_2_label", "category_3_body", "category_3_label", "title"],
      "list_slot_counts": {"category_1_body": 2, "category_2_body": 2, "category_3_body": 2},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {"category_1_label": true, "category_2_label": true, "category_3_label": true, "title": true}
    }
  ],
  "02": [
    {
      "position": "top",
      "template_id": "construction_goals_three_circle_intersection",
      "builder": "cycle_intersect_3",
      "slot_names": ["circle_1_label", "circle_2_label", "circle_3_label", "intersection", "title"],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {"circle_1_label": true, "circle_2_label": true, "circle_3_label": true, "intersection": false, "title": true}
    },
    {
      "position": "bottom",
      "template_id": "__empty__",
      "builder": null,
      "slot_names": [],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {}
    }
  ],
  "03": [
    {
      "position": "left",
      "template_id": "three_parallel_requirements",
      "builder": "items_with_role",
      "slot_names": ["pillars", "title"],
      "list_slot_counts": {"pillars": 3},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {"title": true}
    },
    {
      "position": "right",
      "template_id": "process_product_two_way",
      "builder": "process_product_pair",
      "slot_names": ["banner_left", "banner_right", "process", "product", "title"],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {"process": {"sections": 3}, "product": {"sections": 3}},
      "string_slot_nonempty": {"banner_left": true, "banner_right": true, "title": true}
    }
  ],
  "04": [
    {
      "position": "top",
      "template_id": "bim_issues_quadrant_four",
      "builder": "quadrant_flat_slots",
      "slot_names": ["quadrant_1_body", "quadrant_1_label", "quadrant_2_body", "quadrant_2_label", "quadrant_3_body", "quadrant_3_label", "quadrant_4_body", "quadrant_4_label", "title"],
      "list_slot_counts": {"quadrant_1_body": 2, "quadrant_2_body": 2, "quadrant_3_body": 2, "quadrant_4_body": 2},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {"quadrant_1_label": true, "quadrant_2_label": true, "quadrant_3_label": true, "quadrant_4_label": true, "title": true}
    },
    {
      "position": "bottom-left",
      "template_id": "__empty__",
      "builder": null,
      "slot_names": [],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {}
    },
    {
      "position": "bottom-right",
      "template_id": "__empty__",
      "builder": null,
      "slot_names": [],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {}
    }
  ],
  "05": [
    {
      "position": "primary",
      "template_id": "__empty__",
      "builder": null,
      "slot_names": [],
      "list_slot_counts": {},
      "dict_slot_sub_counts": {},
      "string_slot_nonempty": {}
    }
  ]
}