{
  "version": "v1",
  "date": "2026-10-18",
  "source": "data/core_books.csv",
  "policy": "One row per exact system_name. Assign a family only when every source record for that system resolves to the same shared family. Preserve explicit Standalone labels; leave ambiguous and unsupported cases unclassified. A family must have at least two distinct source system names associated with its normalized labels, even if one of those systems remains unclassified across editions.",
  "groups": [
    {
      "id": "dnd-d20",
      "name": "D&D / d20",
      "source_labels": ["d20 System", "Archmage Engine / d20", "D&D / AD&D", "AD&D-derived", "D&D 5e", "D&D / OSR", "D&D / OSR (Without Number)", "D&D Basic", "D&D Basic / B-X", "D&D Basic / BECMI", "d20 System / D&D", "D&D 4e", "d20 System / Pathfinder", "Pathfinder 2e", "Pathfinder 2e / Starfinder 2e", "Mastercraft / d20", "d20 System / Saga", "d20-derived", "d20-derived / True20"],
      "note": "Broad v1 grouping of the catalogue's D&D, d20, Pathfinder and related labels. Specific Mork Borg, Into the Odd and Mutants & Masterminds labels remain separate. OSR alone is not enough for assignment."
    },
    {
      "id": "basic-role-playing",
      "name": "Basic Role-Playing",
      "source_labels": ["Basic Role-Playing", "Basic Role-Playing-derived", "Basic Role-Playing-derived / Dragonbane", "Basic Role-Playing / RuneQuest", "Basic Role-Playing / RuneQuest-derived", "Pendragon / Basic Role-Playing-derived"],
      "note": "Groups the catalogue's explicit BRP and BRP-derived labels, including RuneQuest-related labels."
    },
    {
      "id": "powered-by-the-apocalypse",
      "name": "Powered by the Apocalypse",
      "source_labels": ["Powered by the Apocalypse", "Powered by the Apocalypse-derived / City of Mist", "Ironsworn / Powered by the Apocalypse-derived"],
      "note": "Includes the catalogue's explicit PbtA-derived labels. Forged in the Dark remains separate."
    },
    {
      "id": "fate-fudge",
      "name": "Fate / Fudge",
      "source_labels": ["Fate", "Fate / Fudge", "Fudge", "Fate Accelerated"],
      "note": "Broad v1 grouping retaining the Fate/Fudge relationship already recorded in the catalogue."
    },
    {
      "id": "d6-system",
      "name": "D6 / OpenD6",
      "source_labels": ["D6 System", "D6 Legend", "Mini Six / OpenD6", "OpenD6"],
      "note": "Groups the named D6/OpenD6 labels. A generic label mentioning six-sided dice is not enough for assignment."
    },
    {
      "id": "torg-masterbook",
      "name": "Torg / MasterBook",
      "source_labels": ["Torg / MasterBook", "MasterBook", "Torg"],
      "note": "Retains the Torg/MasterBook relationship recorded in the catalogue."
    },
    {
      "id": "unisystem",
      "name": "Unisystem",
      "source_labels": ["Unisystem", "Cinematic Unisystem"],
      "note": "Groups the two named Unisystem variants."
    },
    {
      "id": "rolemaster",
      "name": "Rolemaster",
      "source_labels": ["Rolemaster", "Rolemaster-derived / HARP"],
      "note": "Includes the catalogue's explicitly Rolemaster-derived label."
    },
    {
      "id": "earthdawn-step-system",
      "name": "Earthdawn / Step System",
      "source_labels": ["Step System / Earthdawn", "Earthdawn-derived"],
      "note": "Groups the catalogue's Earthdawn and Earthdawn-derived labels."
    },
    {
      "id": "mork-borg",
      "name": "Mörk Borg",
      "source_labels": ["Mörk Borg", "Mörk Borg / OSR"],
      "note": "Keeps the specifically named Mork Borg grouping separate from the broad D&D/d20 grouping."
    },
    {
      "id": "cortex",
      "name": "Cortex",
      "source_labels": ["Cortex", "Cortex Plus", "Cortex Prime"],
      "note": "Groups the named Cortex variants."
    },
    {
      "id": "gumshoe",
      "name": "GUMSHOE",
      "source_labels": ["GUMSHOE", "GUMSHOE One-2-One"],
      "note": "Includes the named One-2-One variant. A label describing a precursor is not treated as membership."
    },
    {
      "id": "mutants-and-masterminds",
      "name": "Mutants & Masterminds",
      "source_labels": ["d20-derived / Mutants & Masterminds", "Mutants & Masterminds 3e"],
      "note": "Keeps the specifically named Mutants & Masterminds grouping separate from the broad D&D/d20 grouping."
    }
  ],
  "ambiguous_labels": ["d20 System / Tri-Stat", "Interlock / Fuzion"],
  "excluded_relationship_labels": ["Dying Earth / GUMSHOE precursor", "OSR / Death in Space"]
}