{
  "id": "sunfish-20-20261028",
  "title": "Twenty games against Sunfish",
  "date": "2026-10-28",
  "kind": "evaluation",
  "status": "completed",
  "hypothesis": "Measure how the full-month checkpoint behaves in a small, reproducible match with declared assistance.",
  "baseline": "Sunfish classic at recorded commit e396948acbd80cdcbad3dccfb07e878fba9df8f4. Requested 1,000 nodes; reported work ranged from 1,000 to 11,422 nodes.",
  "data": "All 20 games: ten hand-authored openings, both colors. No games selected by outcome; all 20 terminated by game rules.",
  "config": {
    "decoding": "full legal-move joint argmax; raw probabilities separately logged; tactical override skips model",
    "draw_policy": "immediate symmetric python-chess outcome(claim_draw=True)",
    "games": 20,
    "mate_max_plies": 3,
    "mate_nodes": 50000,
    "mate_seconds": 1,
    "opening_provenance": "Ten hand-authored common opening sequences selected before play; no database/engine/test-set selection",
    "ply_cap_including_opening": 256,
    "seed": 20261028,
    "sunfish_commit": "e396948acbd80cdcbad3dccfb07e878fba9df8f4",
    "sunfish_requested_nodes": 1000
  },
  "compute": "656 total system decisions: 651 model queries and five mate-helper overrides that skipped the model. Total recorded game time 410.58 seconds.",
  "results": [
    {
      "label": "Wins",
      "value": 3
    },
    {
      "label": "Draws",
      "value": 0
    },
    {
      "label": "Losses",
      "value": 17
    },
    {
      "label": "Mate-helper moves",
      "value": 5
    },
    {
      "label": "Raw greedy legal queries",
      "value": 591
    }
  ],
  "limitations": [
    "20 games and one opponent setting do not establish Elo.",
    "Played moves use joint argmax over legal moves; raw model legality is a distinct diagnostic.",
    "Five forced-mate helper overrides are assisted decisions, not model predictions.",
    "Sunfish actual node count exceeded the requested budget in some searches.",
    "No model-only ablation was played for these 20 positions.",
    "All three wins contained helper overrides. No model-only ablation establishes that those overrides were necessary to win. Helper use is 5/656 total decisions; raw-greedy legality is 591/651 model queries."
  ],
  "checkpoint": "6133648b2926b38542ee3ee1251a1ba111d61da9a8ea69d1c5f0559b09933643",
  "sourceSnapshot": "match-20261028",
  "history": [],
  "evidence": [
    {
      "label": "summary.json",
      "sha256": "fe9fc2d40a5c718fd6eeafeaaded44220057e5e662597c89c07132f05424d28c",
      "selectedFields": {
        "by_colour": {
          "black": {
            "draws": 0,
            "losses": 9,
            "unfinished": 0,
            "wins": 1
          },
          "white": {
            "draws": 0,
            "losses": 8,
            "unfinished": 0,
            "wins": 2
          }
        },
        "capped_games": 0,
        "completed_games": 20,
        "failed_games": 0,
        "mean_raw_legal_probability": 0.8775225006586275,
        "model_queries": 651,
        "overrides": 5,
        "raw_greedy_legal": 591,
        "seconds_since_start": 420.33469025799997,
        "sunfish_reported_nodes_range": [
          1000,
          11422
        ],
        "sunfish_requested_nodes": 1000,
        "tactical_unknown": 0,
        "terminal_games": 20,
        "timeout_games": 0,
        "total_game_seconds": 410.580232404
      }
    }
  ]
}