The hand-rolled scoring heuristic lost to a random-move baseline 7-7 in
self-play — far below the spec's >=80% acceptance bar. Swap in a real
chess engine (js-chess-engine, MIT, ~400KB, no native deps) for vanilla
mode at level 2 with randomness=30 to break threefold cycles.
- BrainInput.fen added; driver populates it ONLY in vanilla mode.
Blind mode omits the FEN so the engine path can't smuggle opponent
positions past the view filter.
- CasualBrain in vanilla: convert FEN -> EngineGame -> ai({level: 2});
validate the engine's move is in legalCandidates; fall back to
heuristic on miss.
- Blind mode unchanged (engine isn't useful when only own pieces are
visible — that's Phase 2 Recon's territory).
Self-play vs RandomBrain (100 games each direction, vanilla):
- Casual(W) vs Random(B): W=97%
- Random(W) vs Casual(B): B=96%
Casual-vs-Casual vanilla balanced, ~5-30ms/move. All 54 tests still pass.
Refresh .secrets.baseline (stale) to allow new pnpm-lock.yaml hashes.
- maybeAbandon Promise no longer floats from setTimeout
- broadcastSinceLast loses dead extra parameter
- bot-slot token is randomized so a third party can't hijack the
bot's color by guessing a fixed placeholder
Replace broadcastNewAnnouncements/broadcastUpdate with watermark-based
broadcastSinceLast; add pokeBot helper; make all state-mutating handlers
async; hook pokeBot after every mutation so the CasualBrain fires on
each turn without oracle access.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Extract endGame/finalizeIfEnded to game-end.ts so driver.ts can call
finalizeIfEnded after an applied move (fix: bot checkmate was not
setting game.status='finished'). Wrap entire dispatch() call in
try/catch for exception safety. Move lastSeenAnnouncementCount advance
to after successful dispatch so retry attempts see FSM rejection
announcements. Add checkmate-finalize test; lock retry-cap at 5 calls.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Wires Brain to Game: init/onStateChange/dispose lifecycle, in-flight
mutex, 5-attempt retry loop with attemptHistory, resign-on-cap. Also
adds Game.aiOpponent? field to state.ts for Task 5.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
claude (blind_chess)