coolguy 44b8faba3d docs(research): SO-ISMCTS BC ceiling write-up from 2026-05-11 autonomous session
Summarizes the 13-cycle trap-exploration session: BC pretrain (heuristic
clone) is the self-play ceiling under our compute budget (1 GPU + 50
sims + 768x4 MLP). All variants (naive finetune, KL anchor, mirror
descent, mixed-opponent + opponent-aware search) either preserved BC
(~17-21/100 vs heuristic-cautious) or regressed to catastrophic
forgetting. The single largest improvement of the session — 4× win rate
on the same checkpoint — came from PUCT Q-value normalization at search
time, not from any learning change.

Records the mechanism (negative training signal from BC-vs-heuristic
games; search too shallow to find heuristic-beating moves), the
hypotheses we negated, and the dials left in code for future runs with
more compute.
2026-05-11 20:45:10 +09:00
2026-05-08 16:22:52 +09:00
2026-05-07 15:42:30 +09:00

coolrl-lost-cities

Focused Lost Cities extraction from the legacy coolrl repository.

The current implementation starts with the classic two-player card game:

  • classic 5-expedition rules by default
  • Python/Cython game engine
  • env wrapper
  • random, discard-only, and safe-heuristic bots
  • core rule, scoring, mask, env, canonical-state, bot, and GUI smoke tests

Training code, Deep CFR, learned-policy evaluation, GUI, and web client are intentionally outside the first port.

Development

uv run pytest tests/games/classic
uv run lost-cities-classic

For future GUI work, install the optional GUI dependencies:

uv sync --extra gui

Run the classic pygame GUI:

uv run lost-cities-classic-gui --mode pvc --bot safe-heuristic

The GUI uses the in-process Cython game engine.

Basic Usage

from coolrl_lost_cities.games.classic import GameState, build_bot, classic_config

state = GameState.new_game(classic_config(seed=1))
bot = build_bot("random", seed=1)

while not state.terminal:
    state.apply_action(bot.act(state))

print(state.total_score(0), state.total_score(1))

See classic port notes for the current direction.

S
Description
Lost Cities
Readme
7.7 MiB
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Python 73.3%
Cython 21.7%
Julia 4.8%
Shell 0.2%