{
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    "generated_at_utc": "2026-10-20T14:04:40.241962+00:00",
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    "platform": "Windows-10-10.0.19045-SP0"
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    "title": "Burrows vs Turner: three choices in a rook-sacrifice battle",
    "source": {
      "label": "Wigston Chess Club Games and Puzzles page",
      "url": "https://www.wigstonchess.org.uk/games-and-puzzles.html"
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                "f6h7",
                "d3c2",
                "d2e3",
                "c2b1q",
                "h1b1",
                "a2b1",
                "f2h4",
                "b1d3",
                "e3f2",
                "d3d4",
                "f2e2",
                "g7h7",
                "a1b3",
                "d4f4",
                "h4f4",
                "h6f4"
              ],
              "san": "28. Nxh7 dxc2 29. Ke3 cxb1=Q 30. Rxb1 Qxb1 31. Qh4 Qd3+ 32. Kf2 Qd4+ 33. Ke2 Kxh7 34. Nb3 Qxf4 35. Qxf4 Bxf4"
            },
            "nodes": 251059,
            "depth": 14,
            "seldepth": 31
          },
          {
            "move": {
              "uci": "h1f1",
              "san": "Rhf1"
            },
            "is_played_move": true,
            "is_engine_best_move": false,
            "selected_by_models": [],
            "score": {
              "centipawns": -409,
              "is_mate": false,
              "mate_in": null,
              "comparison_cp": -409
            },
            "loss_cp": 316,
            "within_100cp": false,
            "within_200cp": false,
            "pv": {
              "uci": [
                "h1f1",
                "d3c2",
                "b1b6",
                "c2c1r",
                "d2c1",
                "a2a1",
                "c1d2",
                "a1e5",
                "f2e3",
                "a8d8",
                "d2e2",
                "f5d3",
                "e2f3",
                "e5e3",
                "f3e3",
                "d3f1",
                "g2g4",
                "g7h8"
              ],
              "san": "28. Rhf1 dxc2 29. Rb6 c1=R+ 30. Kxc1 Qxa1+ 31. Kd2 Qxe5 32. Qe3 Rd8+ 33. Ke2 Bd3+ 34. Kf3 Qxe3+ 35. Kxe3 Bxf1 36. g4 Kh8"
            },
            "nodes": 250175,
            "depth": 17,
            "seldepth": 32
          }
        ]
      }
    },
    {
      "id": "escape-32",
      "label": "White to move on move 32",
      "fen": "8/5pkp/5Npb/p1p1Pb2/5P2/4Q3/2p3PP/NqRrKR2 w - - 6 32",
      "side_to_move": "white",
      "legal_move_count": 3,
      "played_move": {
        "uci": "e1f2",
        "san": "Kf2"
      },
      "model_consensus": {
        "distinct_top_moves": 1,
        "most_selected_move": {
          "uci": "c1d1",
          "san": "Rxd1"
        },
        "most_selected_count": 6
      },
      "public_choice_gate": {
        "required_distinct_safe_model_moves": 3,
        "safety_threshold_cp": 100,
        "observed_distinct_model_moves": 1,
        "safe_distinct_model_moves": 0,
        "passes": false
      },
      "models": [
        {
          "key": "v6_active",
          "label": "V6 Active",
          "intended_profile": "active, initiative-seeking",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 525.479361
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 525.479361
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 194.121919
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 194.049709
            }
          ]
        },
        {
          "key": "v8_sharp",
          "label": "V8 Sharp",
          "intended_profile": "sharp club-player profile on curated data",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 531.717513
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 531.717513
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 196.869728
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 196.83502
            }
          ]
        },
        {
          "key": "v9_positional",
          "label": "V9 Positional",
          "intended_profile": "calm positional pressure",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 533.072845
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 533.072845
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 197.077319
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 197.046155
            }
          ]
        },
        {
          "key": "v15_endgame",
          "label": "V15 Endgame",
          "intended_profile": "endgame-focused distilled evaluator",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 555.370578
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 555.370578
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 200.051501
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 200.020685
            }
          ]
        },
        {
          "key": "v17_file_pressure",
          "label": "V17 File Pressure",
          "intended_profile": "open-file and rook-pressure weighting",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 531.563232
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 531.563232
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 197.440518
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 197.408836
            }
          ]
        },
        {
          "key": "v18_defensive",
          "label": "V18 Defensive",
          "intended_profile": "defensive tension and counterpunch weighting",
          "top_move": {
            "uci": "c1d1",
            "san": "Rxd1",
            "hybrid_score_cp": 522.846011
          },
          "top_three": [
            {
              "uci": "c1d1",
              "san": "Rxd1",
              "hybrid_score_cp": 522.846011
            },
            {
              "uci": "e1e2",
              "san": "Ke2",
              "hybrid_score_cp": 195.213953
            },
            {
              "uci": "e1f2",
              "san": "Kf2",
              "hybrid_score_cp": 195.152325
            }
          ]
        }
      ],
      "stockfish": {
        "best_move": {
          "uci": "e1f2",
          "san": "Kf2"
        },
        "best_score": {
          "centipawns": -47,
          "is_mate": false,
          "mate_in": null,
          "comparison_cp": -47
        },
        "best_pv": {
          "uci": [
            "e1f2",
            "b1c1",
            "e3c1",
            "d1c1",
            "f1c1",
            "h6f4",
            "c1c2",
            "f4e5",
            "f6e8",
            "g7f8",
            "c2a2",
            "f8e8",
            "a2a5",
            "e5c7",
            "a5a4",
            "e8d7",
            "a1b3",
            "d7c6",
            "b3d2",
            "f5e6",
            "d2f3",
            "h7h5",
            "a4a8",
            "c5c4"
          ],
          "san": "32. Kf2 Qxc1 33. Qxc1 Rxc1 34. Rxc1 Bxf4 35. Rxc2 Bxe5 36. Ne8+ Kf8 37. Ra2 Kxe8 38. Rxa5 Bc7 39. Ra4 Kd7 40. Nb3 Kc6 41. Nd2 Be6 42. Nf3 h5 43. Ra8 c4"
        },
        "nodes": 250337,
        "depth": 18,
        "seldepth": 32,
        "verified_choices": [
          {
            "move": {
              "uci": "c1d1",
              "san": "Rxd1"
            },
            "is_played_move": false,
            "is_engine_best_move": false,
            "selected_by_models": [
              "V15 Endgame",
              "V17 File Pressure",
              "V18 Defensive",
              "V6 Active",
              "V8 Sharp",
              "V9 Positional"
            ],
            "score": {
              "centipawns": null,
              "is_mate": true,
              "mate_in": -4,
              "comparison_cp": -99996
            },
            "loss_cp": 99949,
            "within_100cp": false,
            "within_200cp": false,
            "pv": {
              "uci": [
                "c1d1",
                "c2d1q",
                "e1f2",
                "d1f1",
                "f2g3",
                "b1e1",
                "e3e1",
                "f1f4"
              ],
              "san": "32. Rxd1 cxd1=Q+ 33. Kf2 Qxf1+ 34. Kg3 Qbe1+ 35. Qxe1 Qxf4#"
            },
            "nodes": 247297,
            "depth": 49,
            "seldepth": 9
          },
          {
            "move": {
              "uci": "e1f2",
              "san": "Kf2"
            },
            "is_played_move": true,
            "is_engine_best_move": true,
            "selected_by_models": [],
            "score": {
              "centipawns": -49,
              "is_mate": false,
              "mate_in": null,
              "comparison_cp": -49
            },
            "loss_cp": 0,
            "within_100cp": true,
            "within_200cp": true,
            "pv": {
              "uci": [
                "e1f2",
                "f5d3",
                "f6e8",
                "g7h8",
                "f1e1",
                "b1c1",
                "e3c1",
                "d1c1",
                "e1c1",
                "h6f4",
                "c1c2",
                "d3c2",
                "a1c2",
                "f4e5"
              ],
              "san": "32. Kf2 Bd3 33. Ne8+ Kh8 34. Re1 Qxc1 35. Qxc1 Rxc1 36. Rxc1 Bxf4 37. Rxc2 Bxc2 38. Nxc2 Bxe5"
            },
            "nodes": 250337,
            "depth": 18,
            "seldepth": 36
          }
        ]
      }
    }
  ],
  "limitations": [
    "The six neural checkpoints are scalar evaluators, not move-policy models or explanation models.",
    "Their 768 inputs encode piece placement only; side to move is applied after inference, while castling rights, en-passant state, repetition, move history, and clocks are not model inputs.",
    "Profile labels describe intended training or runtime behavior and do not prove human-like personality or internal understanding.",
    "Stockfish results use a fixed node budget and configuration and are a verification snapshot, not a claim of perfect play.",
    "Stockfish was required to use two search threads. Parallel search can produce small score, depth, node-count, or PV differences on a fresh rerun even when the configured node limit is unchanged.",
    "Centipawn loss uses a 100,000 cp comparison value for forced-mate scores; mate status and mate distance are also reported separately.",
    "The analysis does not measure Elo, playing strength, or clean unseen test accuracy.",
    "Any reader-facing move explanation must describe observable chess features; it must not be presented as the model's internal reasoning."
  ]
}