Always forbid bids that add up to the cards in hand

The sum of all bids may never equal the number of cards each player
holds in the round; the last bidder has to adjust their bid. This was an
optional "not equal" lobby setting and is now a fixed rule of the game
engine, so it applies to humans, AI players and training alike.

- Remove GameOptions.not_equal, the set_options field, the lobby toggle
  and the --not-equal training flag
- Explain the rule in the lobby and show the blocked bid while bidding
- Drop the option from the AI observation encoding
- Tests check that no round ends with bids summing to the cards in hand

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

wizard_ai/tests/test_ai.py

@@ -30,7 +30,7 @@ def test_action_space_round_trip():
 
 @pytest.mark.parametrize("agent", [HeuristicAgent(), RandomAgent(1), ModelAgent(UniformPolicy(1))])
 def test_agents_play_legal_games(agent):
-    game = WizardGame(4, GameOptions(not_equal=True), seed=3)
+    game = WizardGame(4, seed=3)
     while not game.is_finished:
         obs = game.observation(game.current_player)
         action = agent.act(obs)

wizard_ai/wizard_ai/__main__.py

@@ -33,7 +33,6 @@ def main() -> None:
     train.add_argument("--episodes", type=int, default=1000)
     train.add_argument("--players", default="3,4,5,6", help="comma separated player counts")
     train.add_argument("--opponents", default="self", choices=("self", "heuristic", "random"))
-    train.add_argument("--not-equal", action="store_true")
     train.add_argument("--hidden-bids", action="store_true")
     train.add_argument("--resume", action="store_true", help="continue from --out if it exists")
     train.add_argument("--out", default=config.model_path, help="checkpoint directory")
@@ -65,7 +64,7 @@ def main() -> None:
         training_config = TrainingConfig(
             episodes=args.episodes,
             player_counts=tuple(int(n) for n in args.players.split(",")),
-            options=GameOptions(not_equal=args.not_equal, hidden_bids=args.hidden_bids),
+            options=GameOptions(hidden_bids=args.hidden_bids),
             opponents=args.opponents,
             checkpoint_dir=out,
             seed=args.seed,

wizard_ai/wizard_ai/model/encoding.py

@@ -104,7 +104,7 @@ def encode_observation(obs: Observation) -> list[float]:
     features += _one_hot(MAX_PLAYERS - MIN_PLAYERS + 1, n - MIN_PLAYERS)
     features += _one_hot(len(PHASES), PHASES.index(obs.phase) if obs.phase in PHASES else None)
     features += [obs.round_number / MAX_BID, obs.round_number / obs.total_rounds]
-    features += [float(obs.options.not_equal), float(obs.options.hidden_bids)]
+    features += [float(obs.options.hidden_bids)]
     features += _one_hot(MAX_PLAYERS, (me - obs.dealer) % n)  # seat relative to dealer
     features += _one_hot(MAX_PLAYERS, len(obs.current_trick))  # position in the trick
 
@@ -150,7 +150,7 @@ def encode_observation(obs: Observation) -> list[float]:
 
 
 FEATURE_SIZE = (
-    (MAX_PLAYERS - MIN_PLAYERS + 1) + len(PHASES) + 2 + 2 + MAX_PLAYERS + MAX_PLAYERS
+    (MAX_PLAYERS - MIN_PLAYERS + 1) + len(PHASES) + 2 + 1 + MAX_PLAYERS + MAX_PLAYERS
     + DECK_SIZE * 3 + (len(SUITS) + 1) * 2 + DECK_SIZE
     + 5
     + MAX_OPPONENTS * 7

wizard_server/app/protocol.py

@@ -50,7 +50,6 @@ class RemovePlayer(BaseModel):
 
 class SetOptions(BaseModel):
     type: Literal["set_options"]
-    not_equal: bool
     hidden_bids: bool
 
 

wizard_server/app/service.py

@@ -126,9 +126,9 @@ class WizardService:
                     seat.session.send(protocol.error("You were removed from the lobby"))
                     self._send_no_lobby(seat.session)
                 lobby.broadcast()
-            case protocol.SetOptions(not_equal=not_equal, hidden_bids=hidden_bids):
+            case protocol.SetOptions(hidden_bids=hidden_bids):
                 lobby = self._lobby_of(session)
-                lobby.set_options(session, GameOptions(not_equal=not_equal, hidden_bids=hidden_bids))
+                lobby.set_options(session, GameOptions(hidden_bids=hidden_bids))
                 lobby.broadcast()
             case protocol.StartGame():
                 lobby = self._lobby_of(session)

wizard_server/game_logic/README.md

@@ -11,7 +11,7 @@ pip install ./wizard_server/game_logic
 import random
 from wizard_game import WizardGame, GameOptions
 
-game = WizardGame(num_players=4, options=GameOptions(not_equal=True), seed=1)
+game = WizardGame(num_players=4, options=GameOptions(hidden_bids=True), seed=1)
 rng = random.Random(1)
 while not game.is_finished:
     player = game.current_player

wizard_server/game_logic/tests/test_game.py

@@ -38,15 +38,14 @@ def play_random_game(num_players: int, seed: int, options: GameOptions | None =
 @pytest.mark.parametrize("num_players", [3, 4, 5, 6])
 @pytest.mark.parametrize("seed", range(5))
 def test_random_games_complete(num_players, seed):
-    options = GameOptions(not_equal=seed % 2 == 0, hidden_bids=seed % 3 == 0)
+    options = GameOptions(hidden_bids=seed % 2 == 0)
     game = play_random_game(num_players, seed, options)
     assert game.phase is Phase.FINISHED
     assert len(game.round_history) == game.total_rounds
     assert game.scores == list(game.round_history[-1].scores)
     for result in game.round_history:
         assert sum(result.tricks) == result.round_number
-        if options.not_equal:
+        assert sum(result.bids) != result.round_number
-            assert sum(result.bids) != result.round_number
 
 
 def test_invalid_player_count():
@@ -94,8 +93,8 @@ def test_wizard_trump_card_lets_dealer_choose():
     assert game.current_player == 2
 
 
-def test_not_equal_restricts_last_bidder():
+def test_sum_of_bids_never_equals_cards_in_hand():
-    game = WizardGame(3, GameOptions(not_equal=True), seed=11, first_dealer=0)
+    game = WizardGame(3, seed=11, first_dealer=0)
     if game.phase is Phase.TRUMP_SELECTION:
         game.apply(game.current_player, ChooseTrump(Suit.RED))
     game.apply(1, Bid(0))
@@ -112,8 +111,8 @@ def test_hidden_bids():
     assert game.observation(2).bids[1] is None
     assert game.observation(2).has_bid[1] is True
     game.apply(2, Bid(0))
-    game.apply(0, Bid(0))
+    game.apply(0, Bid(1))  # 0 is not allowed: the bids would add up to the 1 card in hand
-    assert game.observation(2).bids == (0, 1, 0)
+    assert game.observation(2).bids == (1, 1, 0)
 
 
 def test_last_round_has_no_trump():

wizard_server/game_logic/wizard_game/game.py

@@ -217,11 +217,14 @@ class WizardGame:
         return rnd
 
     def _allowed_bids(self, player: int) -> list[int]:
+        """Bids 0..cards in hand, except that the last bidder may not make the
+        sum of all bids equal the number of cards each player holds this round.
+        """
         rnd = self.round
         allowed = list(range(rnd.round_number + 1))
         placed = [bid for bid in rnd.bids if bid is not None]
         is_last_bidder = len(placed) == self.num_players - 1 and rnd.bids[player] is None
-        if self.options.not_equal and is_last_bidder:
+        if is_last_bidder:
             forbidden = rnd.round_number - sum(placed)
             allowed = [bid for bid in allowed if bid != forbidden]
         return allowed

wizard_server/game_logic/wizard_game/state.py

@@ -18,21 +18,18 @@ class Phase(str, Enum):
 
 @dataclass(frozen=True, slots=True)
 class GameOptions:
-    # "notequal": the sum of all bids must not equal the number of tricks
+    # Note: the sum of all bids never equals the number of tricks of a round;
-    # of the round. The last bidder has to adjust their bid.
+    # this is a fixed rule (see ``WizardGame._allowed_bids``), not an option.
-    not_equal: bool = False
+
     # "hiddentip": bids are revealed only once every player has bid.
     hidden_bids: bool = False
 
     def to_dict(self) -> dict:
-        return {"not_equal": self.not_equal, "hidden_bids": self.hidden_bids}
+        return {"hidden_bids": self.hidden_bids}
 
     @classmethod
     def from_dict(cls, data: dict[str, Any]) -> GameOptions:
-        return cls(
+        return cls(hidden_bids=bool(data.get("hidden_bids", False)))
-            not_equal=bool(data.get("not_equal", False)),
-            hidden_bids=bool(data.get("hidden_bids", False)),
-        )
 
 
 @dataclass(frozen=True, slots=True)

wizard_server/tests/test_server.py

@@ -79,7 +79,7 @@ def test_lobby_flow_and_full_game(client):
     assert "needs" in receive_until(host, lambda m: m["type"] == "error")["message"]
 
     host.send_json({"type": "add_ai"})
-    host.send_json({"type": "set_options", "not_equal": True, "hidden_bids": False})
+    host.send_json({"type": "set_options", "hidden_bids": True})
     host.send_json({"type": "start_game"})
 
     rng = random.Random(0)

wizard_website/src/api/types.ts

@@ -19,7 +19,6 @@ export type Action =
 export type Phase = 'trump_selection' | 'bidding' | 'playing' | 'finished'
 
 export interface GameOptions {
-  not_equal: boolean
   hidden_bids: boolean
 }
 
@@ -115,7 +114,7 @@ export type ClientMessage =
   | { type: 'leave_lobby' }
   | { type: 'add_ai' }
   | { type: 'remove_player'; player_id: string }
-  | { type: 'set_options'; not_equal: boolean; hidden_bids: boolean }
+  | { type: 'set_options'; hidden_bids: boolean }
   | { type: 'start_game' }
   | { type: 'action'; action: Action }
   | { type: 'return_to_lobby' }

wizard_website/src/screens/GameScreen/BidPanel.tsx

@@ -34,7 +34,7 @@ export function BidPanel({ observation, onBid }: BidPanelProps) {
       <p className={styles.hint}>
         {!observation.options.hidden_bids &&
           `Bids so far: ${sum} for ${observation.round_number} trick${observation.round_number > 1 ? 's' : ''}. `}
-        {forbidden.length > 0 && `Not-equal rule: you may not bid ${forbidden.join(', ')}.`}
+        {forbidden.length > 0 && `The bids may not add up to ${observation.round_number}, so you may not bid ${forbidden.join(', ')}.`}
       </p>
     </div>
   )

wizard_website/src/screens/LobbyScreen/LobbyScreen.module.css

@@ -205,3 +205,9 @@
   margin: 0;
   color: var(--text-muted);
 }
+
+.rule {
+  margin: 0 0 4px;
+  color: var(--text-muted);
+  font-size: 14px;
+}

wizard_website/src/screens/LobbyScreen/LobbyScreen.tsx

@@ -98,18 +98,10 @@ export function LobbyScreen({ lobby, playerId, actions }: LobbyScreenProps) {
 
       <section className={styles.card}>
         <h2 className={styles.heading}>Rules</h2>
-        <label className={styles.option}>
+        <p className={styles.rule}>
-          <input
+          The sum of all bids may never equal the number of cards in hand — the last player to bid has
-            type="checkbox"
+          to adjust their bid.
-            checked={lobby.options.not_equal}
+        </p>
-            disabled={!isHost}
-            onChange={(event) => actions.setOptions({ ...lobby.options, not_equal: event.target.checked })}
-          />
-          <span>
-            <strong>Not equal</strong>
-            <small>The sum of all bids must not equal the number of tricks in the round.</small>
-          </span>
-        </label>
         <label className={styles.option}>
           <input
             type="checkbox"