Repetition: alpha-beta seeded the repetition map with only the root
position, so search was blind to positions already reached in the real
game and would happily shuffle into draws when ahead. Reconstruct the
full game-history position hashes by replaying moves and seed the search
state with them; treat a twofold occurrence at non-root nodes as a draw.
Contempt: draws are now scored CONTEMPT (25cp) away from zero, signed by
ply parity, so the bot avoids dead-equal repetitions instead of settling.
Endgame: pure NNUE lacks mating knowledge and stalls KX-vs-K conversions.
Add a MopUp correction (edge-driving + king-proximity) applied only in
lone-king endgames with sufficient mating material; zero elsewhere so
middlegame NNUE output is untouched.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Quiescence tactical filter only flagged capture-promotions, so a quiet
queening on an empty back-rank square was treated as non-tactical and
skipped at the search horizon. A bot could therefore miss a winning
promotion sitting exactly at the horizon and play another move. All bots
(Classical/NNUE/Hybrid) share AlphaBetaSearch and were affected.
Treat every promotion as tactical so quiescence always expands it.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Pre-evaluated NNUE scores from NNUEBot.batchEvaluateRoot are now passed
as root hints into AlphaBetaSearch, improving move ordering at ply 0 before
the TT is populated. Hints are threaded immutably through SearchParams to
satisfy the no-var constraint.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---------
Co-authored-by: Janis Eccarius <eccariusjanis@gmail.com>
Reviewed-on: #83
When classical and NNUE evals diverge above the veto threshold, HybridBot
now re-searches excluding the suspect move and switches to NNUE's preferred
alternative instead of merely logging. BotController maps the expert bot to
HybridBot so tournament auto-join uses it.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Janis
Janis Eccarius