coolguy a501a93223 Cycle 4: revert use_rollout_value=true, scale network 512x3 -> 768x4
c3 showed use_rollout_value=false alone is not the fix: without the
heuristic rollout safety net the random-init network value gives bad
MCTS Q early on, the agent plays more (PA 0.10 -> 0.22+) but eats more
-20 expedition penalties (score worsened from -57 to -97 avg).

Mathematical intuition: in Lost Cities, opening an expedition is a
20-point commitment. Break-even requires rank-sum × (handshakes+1) >= 20.
The model has to learn:
  - which colors to open (based on hand handshake/high-rank holdings)
  - when to commit vs discard
  - card-ordering constraints (ascending only)

This is a moderately rich value function. 512x3 (~800k params, ~290
input dim) might be undersized. Test capacity hypothesis with 768x4
(~2M params) while keeping the rollout safety net so MCTS Q stays
competent.

Other params from c1 kept: c_puct=5, virtual_loss=5, dirichlet
α=0.3/ε=0.4, parallel_simulations=64, n_simulations=50.
2026-05-11 07:03:45 +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
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Julia 4.8%
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