File size: 49,624 Bytes
26bf1c9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
"""

RefereeEnvironment — the central multi-agent orchestrator for CounterFeint.



Owns a turn-based state machine with three roles:



  - Fraudster   proposes / modifies ads      (actions: propose_ad, modify_pending_ad, end_turn, commit_final)

  - Investigator reviews ads                  (actions: investigate, verdict, link_accounts)

  - Auditor     audits the trace post-hoc    (actions: flag_investigator, flag_fraudster, submit_audit_report)



All three WebSocket endpoints (`/ws/fraudster`, `/ws/investigator`, `/ws/auditor`)

share a single `RefereeEnvironment` instance per match, so state mutations

from one role are immediately visible to the others.



State machine:



    fraudster_turn  ─end_turn──────►  investigator_turn ─turn_cap/all_decided──► fraudster_turn  (next round)

          │                                   │

          ├─commit_final───►   audit_phase   ◄┘

          │                                   │

          └─action_cap──► investigator_turn   │                               max_rounds / budget / commit_final

                                              └──────── audit_phase → done ◄─────────────────



Phase 1 keeps the Auditor a no-op scaffold (flags accepted, report accepted, but

graders don't consume them yet).  Phase 2A/B/C plug in real audit logic.

"""

from __future__ import annotations

import logging
import random
import time
from typing import Any, Dict, List, Literal, Optional, Tuple
from uuid import uuid4

from openenv.core.env_server.interfaces import Environment
from openenv.core.env_server.types import Action, Observation

try:
    from ..data.ad_generator import (
        TASK_CONFIGS,
        Ad,
        GeneratedEpisode,
        generate_episode,
    )
    from ..data.episode_loader import extend_episode_with_proposal
    from ..data.tool_registry import INVESTIGATION_TARGETS, InvestigationToolRegistry
    from ..graders.auditor_track_a import (
        investigator_audit_score as track_a_score,
        run_track_a,
    )
    from ..graders.base_grader import (
        EpisodeRecord,
        LinkResult,
        VerdictResult,
        grade_episode,
    )
    from ..graders.multi_agent_rewards import (
        RewardInputs,
        compute_episode_rewards,
    )
    from ..graders.plausibility_score import compute_queue_plausibility
    from ..models import (
        AdFraudState,
        AdReviewAction,
        AdReviewObservation,
        AuditFlag,
        AuditorAction,
        AuditorObservation,
        AuditReport,
        FraudsterAction,
        FraudsterObservation,
        RefereeState,
    )
    from .environment import InvestigatorEnvironment
    from .evidence_ledger import build_evidence_ledger
except ImportError:
    from data.ad_generator import (
        TASK_CONFIGS,
        Ad,
        GeneratedEpisode,
        generate_episode,
    )
    from data.episode_loader import extend_episode_with_proposal
    from data.tool_registry import INVESTIGATION_TARGETS, InvestigationToolRegistry
    from graders.auditor_track_a import (
        investigator_audit_score as track_a_score,
        run_track_a,
    )
    from graders.base_grader import (
        EpisodeRecord,
        LinkResult,
        VerdictResult,
        grade_episode,
    )
    from graders.multi_agent_rewards import (
        RewardInputs,
        compute_episode_rewards,
    )
    from graders.plausibility_score import compute_queue_plausibility
    from models import (
        AdFraudState,
        AdReviewAction,
        AdReviewObservation,
        AuditFlag,
        AuditorAction,
        AuditorObservation,
        AuditReport,
        FraudsterAction,
        FraudsterObservation,
        RefereeState,
    )
    from server.environment import InvestigatorEnvironment
    from server.evidence_ledger import build_evidence_ledger


logger = logging.getLogger(__name__)

Phase = Literal["fraudster_turn", "investigator_turn", "audit_phase", "done"]
Role = Literal["fraudster", "investigator", "auditor"]

# Module-level grader result for parity with the Investigator env (/grader endpoint).
_last_grader_result: Dict[str, Any] = {}


def get_last_grader_result() -> Dict[str, Any]:
    return dict(_last_grader_result)


# Default categories the Fraudster can declare.  Combines plausible legit
# categories (so a sophisticated Fraudster can camouflage) with fraud
# templates (so it can propose obvious-fraud or borderline ads).
DEFAULT_ALLOWED_CATEGORIES: Tuple[str, ...] = (
    # Legit camouflage categories
    "ecommerce",
    "saas",
    "local_service",
    "education",
    "fitness",
    # Fraud / borderline templates
    "fake_giveaway",
    "counterfeit_goods",
    "miracle_cure",
    "advance_fee",
    "fake_crypto",
    "celebrity_endorsement_fraud",
    "clone_brand",
    "gray_area_supplements",
    "network_crypto",
    "network_ecommerce",
    "network_fintech",
    "network_health",
)


class RefereeEnvironment(Environment[Action, Observation, RefereeState]):
    """

    Multi-agent referee. Implements the OpenEnv `Environment` contract with

    a generic `Action`/`Observation` typing — each WebSocket route passes

    role-specific subclasses into `step()` via the `role` kwarg.



    Role-aware entry points (preferred):

      - `reset_match(seed, task_id, episode_id, **knobs)`

      - `step_as_fraudster(action)`

      - `step_as_investigator(action)`

      - `step_as_auditor(action)`

      - `build_<role>_observation()`

    """

    SUPPORTS_CONCURRENT_SESSIONS = True

    # Default knobs (overridable via reset kwargs).
    DEFAULT_MAX_ROUNDS = 4
    DEFAULT_MAX_PROPOSALS = 5
    # Per-turn action caps. Bumped from (3, 6) to (4, 10) so the
    # Investigator can comfortably investigate 2-3 ads per turn AND issue
    # verdicts in the same turn without being force-cut to the auditor
    # mid-thought (the previous (6) cap was triggering the
    # ``max_rounds`` short-circuit on the final round before the
    # Investigator could close out pending verdicts).
    DEFAULT_MAX_FRAUDSTER_ACTIONS_PER_TURN = 4
    DEFAULT_MAX_INVESTIGATOR_ACTIONS_PER_TURN = 10

    # ------------------------------------------------------------------
    # Lifecycle
    # ------------------------------------------------------------------

    def __init__(self) -> None:
        super().__init__()
        self._match_id: str = str(uuid4())
        self._task_id: str = "task_1"
        self._rng = random.Random()

        self._investigator = InvestigatorEnvironment()
        self._episode: Optional[GeneratedEpisode] = None
        self._registry: Optional[InvestigationToolRegistry] = None

        self._phase: Phase = "fraudster_turn"
        self._round_number: int = 0
        self._max_rounds: int = self.DEFAULT_MAX_ROUNDS
        self._max_proposals: int = self.DEFAULT_MAX_PROPOSALS
        self._max_fraudster_actions_per_turn: int = (
            self.DEFAULT_MAX_FRAUDSTER_ACTIONS_PER_TURN
        )
        self._max_investigator_actions_per_turn: int = (
            self.DEFAULT_MAX_INVESTIGATOR_ACTIONS_PER_TURN
        )
        self._allowed_categories: List[str] = list(DEFAULT_ALLOWED_CATEGORIES)

        self._proposals_used: int = 0
        self._actions_this_turn: int = 0

        # Per-role logs (consumed by the Auditor).
        self._fraudster_log: List[Dict[str, Any]] = []
        self._investigator_log: List[Dict[str, Any]] = []
        self._audit_flags: List[AuditFlag] = []
        self._audit_report: Optional[AuditReport] = None

        self._fraudster_committed: bool = False
        self._done: bool = False
        self._end_reason: Optional[str] = None

        self._fraudster_reward_total: float = 0.0
        self._investigator_reward_total: float = 0.0
        self._auditor_reward_total: float = 0.0
        self._grader_score: Optional[float] = None
        self._per_ad_plausibility: Dict[str, float] = {}
        self._audit_ground_truth: Dict[str, int] = {}

        self._last_feedback: Dict[Role, str] = {
            "fraudster": "",
            "investigator": "",
            "auditor": "",
        }

        # Proposal slot_index -> ad_id map, so the Fraudster can modify its
        # own prior proposals without knowing the Referee's ad_id scheme.
        self._proposal_slot_to_ad_id: Dict[int, str] = {}
        # Set inside ``_fraudster_propose_ad`` on success, consumed (and
        # cleared) by ``_serialize_fraudster_action`` so the audit log entry
        # for a propose_ad always carries the resolved ``ad_id`` and slot
        # the env actually allocated, not just the LLM's raw payload (which
        # has no ad_id field for propose_ad).
        self._last_proposed_ad_id: Optional[str] = None
        self._last_proposed_slot: Optional[int] = None

    # ------------------------------------------------------------------
    # OpenEnv surface (generic)
    # ------------------------------------------------------------------

    def reset(

        self,

        seed: Optional[int] = None,

        episode_id: Optional[str] = None,

        **kwargs: Any,

    ) -> Observation:
        """

        Generic reset. Returns the *Fraudster* observation because the

        Fraudster always goes first.  The role-specific endpoints can

        also call `build_<role>_observation()` directly.

        """
        self.reset_match(seed=seed, episode_id=episode_id, **kwargs)
        return self.build_fraudster_observation()

    def step(

        self,

        action: Action,

        timeout_s: Optional[float] = None,

        **kwargs: Any,

    ) -> Observation:
        """

        Role-aware generic step. Expects `role` in kwargs, dispatches to

        the appropriate role-specific step method, and returns that role's

        observation.

        """
        role: Optional[Role] = kwargs.get("role")
        if role == "fraudster":
            return self.step_as_fraudster(action)  # type: ignore[arg-type]
        if role == "investigator":
            return self.step_as_investigator(action)  # type: ignore[arg-type]
        if role == "auditor":
            return self.step_as_auditor(action)  # type: ignore[arg-type]
        raise ValueError(
            "RefereeEnvironment.step(action, role=...) requires a role of "
            "'fraudster', 'investigator', or 'auditor'."
        )

    @property
    def state(self) -> RefereeState:
        inv_state = self._investigator.state
        return RefereeState(
            episode_id=self._match_id,
            step_count=(
                len(self._fraudster_log)
                + len(self._investigator_log)
                + len(self._audit_flags)
            ),
            task_id=self._task_id,
            phase=self._phase,
            round_number=self._round_number,
            max_rounds=self._max_rounds,
            proposals_used=self._proposals_used,
            max_proposals=self._max_proposals,
            actions_this_turn=self._actions_this_turn,
            max_actions_per_turn=(
                self._max_fraudster_actions_per_turn
                if self._phase == "fraudster_turn"
                else self._max_investigator_actions_per_turn
            ),
            investigator_state=inv_state.model_dump() if inv_state else {},
            fraudster_proposals=list(self._fraudster_log),
            investigator_action_log=list(self._investigator_log),
            fraudster_committed=self._fraudster_committed,
            audit_report=(
                self._audit_report.model_dump() if self._audit_report else None
            ),
            fraudster_reward=self._fraudster_reward_total,
            investigator_reward=self._investigator_reward_total,
            auditor_reward=self._auditor_reward_total,
            grader_score=self._grader_score,
            end_reason=self._end_reason,
        )

    # ------------------------------------------------------------------
    # Match setup
    # ------------------------------------------------------------------

    def reset_match(

        self,

        *,

        seed: Optional[int] = None,

        episode_id: Optional[str] = None,

        task_id: Optional[str] = None,

        max_rounds: Optional[int] = None,

        max_proposals: Optional[int] = None,

        max_fraudster_actions_per_turn: Optional[int] = None,

        max_investigator_actions_per_turn: Optional[int] = None,

        allowed_categories: Optional[List[str]] = None,

        episode: Optional[GeneratedEpisode] = None,

    ) -> None:
        """Initialize a fresh match. Sets phase to `fraudster_turn`, round 1."""
        self._match_id = episode_id or str(uuid4())
        self._task_id = task_id or "task_1"
        if self._task_id not in TASK_CONFIGS:
            self._task_id = "task_1"

        effective_seed = (
            seed if seed is not None else hash(uuid4()) & 0xFFFFFFFF
        )
        self._rng = random.Random(effective_seed)

        # Resolve each knob with precedence: explicit kwarg > TaskConfig curriculum > class default.
        task_cfg = TASK_CONFIGS[self._task_id]

        def _resolve(arg_value: Optional[int], cfg_attr: str, default: int) -> int:
            if arg_value is not None:
                return arg_value
            cfg_val = getattr(task_cfg, cfg_attr, None)
            return cfg_val if cfg_val is not None else default

        self._max_rounds = _resolve(max_rounds, "max_rounds", self.DEFAULT_MAX_ROUNDS)
        self._max_proposals = _resolve(
            max_proposals, "max_proposals", self.DEFAULT_MAX_PROPOSALS
        )
        self._max_fraudster_actions_per_turn = _resolve(
            max_fraudster_actions_per_turn,
            "max_fraudster_actions_per_turn",
            self.DEFAULT_MAX_FRAUDSTER_ACTIONS_PER_TURN,
        )
        self._max_investigator_actions_per_turn = _resolve(
            max_investigator_actions_per_turn,
            "max_investigator_actions_per_turn",
            self.DEFAULT_MAX_INVESTIGATOR_ACTIONS_PER_TURN,
        )

        cfg_categories = getattr(task_cfg, "allowed_fraud_categories", None)
        if allowed_categories is not None:
            self._allowed_categories = list(allowed_categories)
        elif cfg_categories:
            self._allowed_categories = list(cfg_categories)
        else:
            self._allowed_categories = list(DEFAULT_ALLOWED_CATEGORIES)

        if episode is not None:
            self._episode = episode
        else:
            self._episode = generate_episode(effective_seed, self._task_id)

        self._registry = InvestigationToolRegistry.from_episode(self._episode)

        self._investigator.reset(
            seed=effective_seed,
            episode_id=self._match_id,
            task_id=self._task_id,
            episode=self._episode,
            registry=self._registry,
            queue_may_grow=True,
        )

        self._phase = "fraudster_turn"
        self._round_number = 1
        self._proposals_used = 0
        self._actions_this_turn = 0
        self._fraudster_log = []
        self._investigator_log = []
        self._audit_flags = []
        self._audit_report = None
        self._fraudster_committed = False
        self._done = False
        self._end_reason = None
        self._fraudster_reward_total = 0.0
        self._investigator_reward_total = 0.0
        self._auditor_reward_total = 0.0
        self._grader_score = None
        self._per_ad_plausibility = {}
        self._audit_ground_truth = {}
        self._proposal_slot_to_ad_id = {}
        self._last_proposed_ad_id = None
        self._last_proposed_slot = None
        self._last_feedback = {
            "fraudster": (
                f"Match started. Round 1 of {self._max_rounds}. "
                f"You may propose up to {self._max_proposals} ads total, "
                f"{self._max_fraudster_actions_per_turn} actions per turn."
            ),
            "investigator": (
                "Waiting for Fraudster to finish their turn. The ad queue may "
                "grow during this episode as the Fraudster proposes new ads."
            ),
            "auditor": "Match in progress. Waiting for audit phase.",
        }

    # ------------------------------------------------------------------
    # Fraudster step handler
    # ------------------------------------------------------------------

    def step_as_fraudster(self, action: FraudsterAction) -> FraudsterObservation:
        self._guard_phase("fraudster_turn", role="fraudster")
        assert self._episode is not None and self._registry is not None

        reward = 0.0
        feedback_parts: List[str] = []
        action_type = action.action_type

        if action_type == "propose_ad":
            reward, msg = self._fraudster_propose_ad(action)
            feedback_parts.append(msg)
            self._actions_this_turn += 1

        elif action_type == "modify_pending_ad":
            reward, msg = self._fraudster_modify_pending_ad(action)
            feedback_parts.append(msg)
            self._actions_this_turn += 1

        elif action_type == "end_turn":
            feedback_parts.append("Fraudster ended turn. Control passes to Investigator.")
            self._transition(to="investigator_turn", note="fraudster end_turn")
            reward = 0.0

        elif action_type == "commit_final":
            feedback_parts.append(
                "Fraudster committed (no more proposals). Jumping to audit phase."
            )
            self._fraudster_committed = True
            self._end_reason = "commit_final"
            self._transition(to="audit_phase", note="fraudster commit_final")
            reward = 0.0

        else:
            feedback_parts.append(f"Unknown Fraudster action_type '{action_type}'.")
            reward = -0.05

        self._fraudster_reward_total += reward
        self._last_feedback["fraudster"] = " ".join(feedback_parts).strip()
        self._fraudster_log.append(self._serialize_fraudster_action(action, reward))

        # Auto-transition guards.
        if (
            self._phase == "fraudster_turn"
            and action_type in ("propose_ad", "modify_pending_ad")
            and self._actions_this_turn >= self._max_fraudster_actions_per_turn
        ):
            self._transition(to="investigator_turn", note="fraudster action cap")

        if (
            self._phase == "fraudster_turn"
            and action_type == "propose_ad"
            and self._proposals_used >= self._max_proposals
        ):
            self._last_feedback["fraudster"] += (
                " Proposal budget exhausted — control will pass to Investigator."
            )
            self._transition(to="investigator_turn", note="proposal budget exhausted")

        return self.build_fraudster_observation(reward=reward)

    def _fraudster_propose_ad(self, action: FraudsterAction) -> Tuple[float, str]:
        if self._proposals_used >= self._max_proposals:
            return -0.05, (
                f"Proposal budget exhausted ({self._proposals_used}/{self._max_proposals})."
            )
        if not action.ad_copy or not action.ad_copy.strip():
            return -0.05, "propose_ad requires non-empty `ad_copy`."
        if not action.category:
            return -0.05, "propose_ad requires `category`."
        if action.category not in self._allowed_categories:
            return -0.05, (
                f"category '{action.category}' not in allowed_categories. "
                f"Use one of: {', '.join(self._allowed_categories)}."
            )
        assert self._episode is not None and self._registry is not None

        proposal_seed = self._rng.randint(0, 2**31 - 1)
        ad = extend_episode_with_proposal(
            episode=self._episode,
            registry=self._registry,
            seed=proposal_seed,
            ad_copy=action.ad_copy,
            category=action.category,
            landing_page_blurb=action.landing_page_blurb,
            targeting_summary=action.targeting_summary,
        )
        slot_index = self._proposals_used
        self._proposal_slot_to_ad_id[slot_index] = ad.ad_id
        self._proposals_used += 1
        # Stash so ``_serialize_fraudster_action`` can attach the resolved
        # ``ad_id`` + ``slot_index`` to this propose_ad's audit log entry
        # (the FraudsterAction itself doesn't carry these — they're env-
        # allocated). Without this the auditor sees ``ad_id=None`` for
        # every propose_ad, which then poisons downstream Track B checks
        # (e.g. ``intrinsic_consistency_check`` cannot key flags onto an
        # ad and ``cross_ad_consistency_audit`` cannot dedupe by ad_id).
        self._last_proposed_ad_id = ad.ad_id
        self._last_proposed_slot = slot_index
        self._investigator.notify_queue_grew(ad.ad_id)

        feedback = (
            f"Proposal #{slot_index + 1} accepted: ad_id={ad.ad_id}, category={ad.category}. "
            f"Queue is now {len(self._episode.ads)} ads."
        )
        return 0.02, feedback

    def _fraudster_modify_pending_ad(self, action: FraudsterAction) -> Tuple[float, str]:
        if action.slot_index is None:
            return -0.05, "modify_pending_ad requires `slot_index`."
        slot = action.slot_index
        if slot not in self._proposal_slot_to_ad_id:
            return -0.05, f"Unknown slot_index {slot}. Propose an ad first."

        ad_id = self._proposal_slot_to_ad_id[slot]
        assert self._episode is not None and self._registry is not None

        # Locked once the Investigator has already rendered a verdict.
        already_decided = self._investigator.verdicts.get(ad_id, {}).get("verdict")
        if already_decided:
            return (
                -0.05,
                f"Cannot modify {ad_id}: Investigator already rendered verdict "
                f"'{already_decided}'.",
            )

        target_ad: Optional[Ad] = None
        for a in self._episode.ads:
            if a.ad_id == ad_id:
                target_ad = a
                break
        if target_ad is None:
            return -0.05, f"Internal error: ad {ad_id} not in episode."

        changes: List[str] = []
        if action.new_ad_copy is not None and action.new_ad_copy.strip():
            target_ad.ad_copy = action.new_ad_copy.strip()[:2000]
            changes.append("ad_copy")

        if action.new_landing_page_blurb is not None and action.new_landing_page_blurb.strip():
            lp = self._episode.landing_pages.get(ad_id)
            if lp is not None:
                from dataclasses import replace
                new_lp = replace(
                    lp, content_summary=action.new_landing_page_blurb.strip()[:2000]
                )
                self._episode.landing_pages[ad_id] = new_lp
                updated_text = new_lp.to_investigation_text()
                self._episode.investigation_data.setdefault(ad_id, {})["landing_page"] = updated_text
                self._registry.update_ad(ad_id, {"landing_page": updated_text})
                changes.append("landing_page")

        if not changes:
            return -0.02, "modify_pending_ad had nothing to change."
        return 0.01, f"Modified {ad_id} fields: {', '.join(changes)}."

    # ------------------------------------------------------------------
    # Investigator step handler
    # ------------------------------------------------------------------

    def step_as_investigator(self, action: AdReviewAction) -> AdReviewObservation:
        self._guard_phase("investigator_turn", role="investigator")
        assert self._episode is not None

        obs = self._investigator.step(action)
        reward = float(obs.reward or 0.0)
        self._investigator_reward_total += reward

        self._investigator_log.append(self._serialize_investigator_action(action, obs))
        self._actions_this_turn += 1
        self._last_feedback["investigator"] = obs.feedback or ""

        # Episode termination paths:
        #   1. Fraudster already committed AND all ads decided -> audit_phase.
        #   2. Max rounds reached AND no more proposals allowed -> audit_phase.
        #   3. Investigator budget exhausted (obs.done) -> audit_phase.
        #   4. Action cap for this turn hit -> fraudster_turn (next round, unless commit_final).

        all_decided = self._all_ads_decided()
        inv_done = bool(obs.done)

        if inv_done:
            self._end_reason = self._end_reason or "investigator_done"
            self._transition(to="audit_phase", note="investigator env signalled done")
            obs.done = False  # match isn't over until Auditor submits
            return obs

        if all_decided and (
            self._fraudster_committed
            or self._round_number >= self._max_rounds
            or self._proposals_used >= self._max_proposals
        ):
            self._end_reason = self._end_reason or "all_decided"
            self._transition(to="audit_phase", note="all ads decided")
            obs.done = False
            return obs

        if self._actions_this_turn >= self._max_investigator_actions_per_turn:
            if self._round_number >= self._max_rounds or self._fraudster_committed:
                self._end_reason = self._end_reason or "max_rounds"
                self._transition(to="audit_phase", note="max rounds reached")
                obs.done = False
            else:
                self._round_number += 1
                self._transition(to="fraudster_turn", note="investigator action cap")
                # One-line warning when the next investigator turn will be
                # the LAST one — gives a slow-to-verdict policy a clear
                # signal that pending ads will get auto-approved otherwise.
                if self._round_number == self._max_rounds:
                    self._last_feedback["investigator"] = (
                        "Final round next: pending ads not given an explicit "
                        "verdict will auto-approve at audit time."
                    )

        obs.done = self._phase == "done"
        return obs

    def _all_ads_decided(self) -> bool:
        if self._episode is None:
            return False
        verdicts = self._investigator.verdicts
        return all(a.ad_id in verdicts for a in self._episode.ads)

    # ------------------------------------------------------------------
    # Auditor step handler
    # ------------------------------------------------------------------

    def step_as_auditor(self, action: AuditorAction) -> AuditorObservation:
        self._guard_phase("audit_phase", role="auditor")

        feedback = ""
        if action.action_type == "flag_investigator":
            flag = AuditFlag(
                track="A",
                target_ad_id=action.target_ad_id,
                flag_type=action.flag_type or "unspecified",
                severity=action.severity if action.severity is not None else 0.5,
                note=action.note or "",
            )
            self._audit_flags.append(flag)
            feedback = (
                f"Track A flag recorded: {flag.flag_type} (severity={flag.severity:.2f})."
            )

        elif action.action_type == "flag_fraudster":
            flag = AuditFlag(
                track="B",
                target_ad_id=action.target_ad_id,
                flag_type=action.flag_type or "unspecified",
                severity=action.severity if action.severity is not None else 0.5,
                note=action.note or "",
            )
            self._audit_flags.append(flag)
            feedback = (
                f"Track B flag recorded: {flag.flag_type} (severity={flag.severity:.2f})."
            )

        elif action.action_type == "submit_audit_report":
            report_payload = action.audit_report or {}
            track_a_flags = [f for f in self._audit_flags if f.track == "A"]
            track_b_flags = [f for f in self._audit_flags if f.track == "B"]

            # Track A/B score *defaults* come from the real graders running
            # over the episode record — so even a dumb Auditor that submits an
            # empty report gets a principled score.  Caller-supplied values
            # override these (used by tests and LLM Auditors that compute
            # their own).
            default_a, default_b = self._compute_default_track_scores()
            investigator_score = float(
                report_payload.get("investigator_audit_score", default_a)
            )
            fraudster_score = float(
                report_payload.get("fraudster_plausibility_score", default_b)
            )
            investigator_score = min(1.0, max(0.0, investigator_score))
            fraudster_score = min(1.0, max(0.0, fraudster_score))

            self._audit_report = AuditReport(
                track_a_flags=track_a_flags,
                track_b_flags=track_b_flags,
                investigator_audit_score=investigator_score,
                fraudster_plausibility_score=fraudster_score,
                notes=str(report_payload.get("notes", "") or action.note or "")[:4000],
            )
            feedback = (
                "Audit report submitted. "
                f"Track A flags: {len(track_a_flags)}. "
                f"Track B flags: {len(track_b_flags)}. "
                f"investigator_audit_score={investigator_score:.2f}, "
                f"fraudster_plausibility_score={fraudster_score:.2f}."
            )
            self._finalize_audit()

        else:
            feedback = f"Unknown Auditor action_type '{action.action_type}'."

        self._last_feedback["auditor"] = feedback
        return self.build_auditor_observation(feedback=feedback)

    def _finalize_audit(self) -> None:
        """

        Compute grader score and per-role rewards using the multi-agent reward

        model (graders/multi_agent_rewards.py), close out the match, and

        transition to `done`.

        """
        if self._episode is None:
            return

        record = self._build_episode_record()
        self._grader_score = grade_episode(record)

        audit_report = self._audit_report or AuditReport(
            track_a_flags=[],
            track_b_flags=[],
            investigator_audit_score=1.0,
            fraudster_plausibility_score=1.0,
            notes="",
        )

        reward_inputs = RewardInputs(
            record=record,
            audit_report=audit_report,
            fraudster_proposal_log=list(self._fraudster_log),
            investigator_action_log=list(self._investigator_log),
            investigation_data_seen=(
                self._registry.to_dict() if self._registry else {}
            ),
            fraudster_ad_ids=list(self._proposal_slot_to_ad_id.values()),
        )
        rewards = compute_episode_rewards(reward_inputs)

        self._fraudster_reward_total = float(rewards["fraudster"])
        self._investigator_reward_total = float(rewards["investigator"])
        self._auditor_reward_total = float(rewards["auditor"])
        self._per_ad_plausibility = dict(rewards.get("per_ad_plausibility") or {})
        self._audit_ground_truth = dict(rewards.get("audit_ground_truth") or {})

        global _last_grader_result
        _last_grader_result = {
            "match_id": self._match_id,
            "task_id": self._task_id,
            "grader_score": self._grader_score,
            "phase": "done",
            "total_steps": (
                len(self._fraudster_log)
                + len(self._investigator_log)
                + len(self._audit_flags)
            ),
            "fraudster_reward": self._fraudster_reward_total,
            "investigator_reward": self._investigator_reward_total,
            "auditor_reward": self._auditor_reward_total,
            "per_ad_plausibility": self._per_ad_plausibility,
            "audit_ground_truth": self._audit_ground_truth,
            "proposals_used": self._proposals_used,
            "end_reason": self._end_reason,
            "audit_report": (
                self._audit_report.model_dump() if self._audit_report else None
            ),
        }

        self._transition(to="done", note="audit report submitted")
        self._done = True

    def _compute_default_track_scores(self) -> Tuple[float, float]:
        """

        Derive default investigator_audit_score and fraudster_plausibility_score

        from the Track A and Track B graders.  Used when the Auditor submits

        an empty report payload.

        """
        if self._episode is None:
            return 1.0, 1.0

        record = self._build_episode_record()
        investigation_data_seen = (
            self._registry.to_dict() if self._registry else {}
        )
        track_a_flags = run_track_a(
            record,
            investigator_actions=list(self._investigator_log),
            investigation_data_seen=investigation_data_seen,
        )
        investigator_score = track_a_score(track_a_flags)

        _per_ad, _flags, queue_plaus = compute_queue_plausibility(
            self._fraudster_log
        )
        # If the Fraudster never proposed anything, plausibility doesn't
        # apply — treat as 1.0 (no evidence the Fraudster was unrealistic).
        return investigator_score, queue_plaus if _per_ad else 1.0

    def _build_episode_record(self) -> EpisodeRecord:
        """Assemble an EpisodeRecord from Investigator's view, mirroring R1."""
        assert self._episode is not None
        verdicts = self._investigator.verdicts
        links = self._investigator.links
        inv_state: AdFraudState = self._investigator.state

        verdict_results = []
        for ad in self._episode.ads:
            v = verdicts.get(ad.ad_id)
            if v:
                verdict_results.append(
                    VerdictResult(
                        ad_id=ad.ad_id,
                        verdict=v["verdict"],
                        confidence=v.get("confidence", 0.5),
                        ground_truth=v["ground_truth"],
                        auto_approved=v.get("auto_approved", False),
                    )
                )

        link_results = [
            LinkResult(ad_id_1=l["ad_id_1"], ad_id_2=l["ad_id_2"], correct=l["correct"])
            for l in links
        ]

        ads_metadata = [
            {
                "ad_id": ad.ad_id,
                "ground_truth": ad.ground_truth_label,
                "severity": ad.severity,
            }
            for ad in self._episode.ads
        ]

        return EpisodeRecord(
            task_id=self._task_id,
            total_steps=inv_state.step_count,
            action_budget=self._episode.task_config.action_budget,
            verdicts=verdict_results,
            links=link_results,
            ads_metadata=ads_metadata,
            n_fraud_rings=len(self._episode.fraud_rings),
            ring_sizes=[len(r.member_ad_ids) for r in self._episode.fraud_rings],
        )

    # ------------------------------------------------------------------
    # Observation builders
    # ------------------------------------------------------------------

    def build_fraudster_observation(

        self, *, reward: float = 0.0

    ) -> FraudsterObservation:
        phase = self._phase
        done = phase == "done"

        if self._episode is None:
            return FraudsterObservation(
                done=done,
                reward=reward,
                feedback="No episode loaded. Call reset() first.",
                phase=phase,
            )

        current_queue = self._build_queue_summary()
        prior_verdicts = self._build_verdict_history()
        investigations = self._investigator.investigations

        rounds_remaining = max(0, self._max_rounds - self._round_number + 1)
        actions_left = max(
            0,
            self._max_fraudster_actions_per_turn - self._actions_this_turn,
        ) if phase == "fraudster_turn" else 0

        my_proposal_signals = self._build_my_proposal_signals()

        return FraudsterObservation(
            done=done,
            reward=reward,
            feedback=self._last_feedback["fraudster"],
            phase=phase,
            task_id=getattr(self._episode.task_config, "task_id", ""),
            round_number=self._round_number,
            rounds_remaining=rounds_remaining,
            proposals_used=self._proposals_used,
            proposals_remaining=max(0, self._max_proposals - self._proposals_used),
            actions_left_this_turn=actions_left,
            current_queue=current_queue,
            prior_verdicts=prior_verdicts,
            investigation_targets_used=investigations,
            allowed_categories=list(self._allowed_categories),
            my_proposal_signals=my_proposal_signals,
        )

    def _build_my_proposal_signals(self) -> Dict[str, Dict[str, Any]]:
        """Per-proposal structured signals for the Fraudster's own ads.



        For every Fraudster-proposed ad, expose the auto-assigned underlying

        signals (payment_id, registrar, domain, country, account_age_days,

        targeting_fingerprint) by reusing the same extraction logic the

        Investigator's evidence ledger uses.  We synthesise an

        "investigations" dict that pretends *all* targets were pulled — the

        Fraudster authored these ads, so it is allowed to know everything

        the env auto-assigned to them.  The Fraudster never sees signals

        for synthetic / non-self-proposed ads, only for its own slate.

        """
        if self._episode is None:
            return {}
        proposal_ad_ids = list(self._proposal_slot_to_ad_id.values())
        if not proposal_ad_ids:
            return {}

        full_targets = [
            "payment_method",
            "landing_page",
            "targeting_overlap",
            "advertiser_history",
        ]
        ledger = build_evidence_ledger(
            episode=self._episode,
            registry=self._registry,
            ad_ids=proposal_ad_ids,
            investigations={ad_id: full_targets for ad_id in proposal_ad_ids},
        )

        slot_by_ad_id = {
            ad_id: slot for slot, ad_id in self._proposal_slot_to_ad_id.items()
        }
        verdicts = self._investigator.verdicts
        for ad_id, entry in ledger.items():
            if ad_id in slot_by_ad_id:
                entry["slot_index"] = slot_by_ad_id[ad_id]
            v = verdicts.get(ad_id)
            entry["investigator_verdict"] = (
                v.get("verdict") if v else "pending"
            )
        return ledger

    def build_investigator_observation(self) -> AdReviewObservation:
        obs = self._investigator._build_observation(  # noqa: SLF001
            reward=0.0, done=(self._phase == "done")
        )
        obs.feedback = (
            self._last_feedback["investigator"] or obs.feedback
        )
        return obs

    def build_auditor_observation(

        self, *, feedback: str = ""

    ) -> AuditorObservation:
        phase = self._phase
        done = phase == "done"
        investigation_data_seen: Dict[str, Dict[str, str]] = {}
        if self._registry is not None:
            investigation_data_seen = self._registry.to_dict()

        record: Dict[str, Any] = {}
        if self._episode is not None:
            record = {
                "task_id": self._task_id,
                "round_number": self._round_number,
                "proposals_used": self._proposals_used,
                "end_reason": self._end_reason,
                "ads": [
                    {
                        "ad_id": ad.ad_id,
                        "ad_copy": ad.ad_copy,
                        "category": ad.category,
                        "ground_truth": ad.ground_truth_label,
                        "severity": ad.severity,
                        "fraud_type": ad.fraud_type,
                        "difficulty": ad.difficulty,
                        "is_fraudster_proposal": ad.ad_id
                        in self._proposal_slot_to_ad_id.values(),
                    }
                    for ad in self._episode.ads
                ],
                "verdicts": [
                    {"ad_id": ad_id, **v}
                    for ad_id, v in self._investigator.verdicts.items()
                ],
                "links": list(self._investigator.links),
                "grader_score": self._grader_score,
                "fraud_rings": [
                    {
                        "ring_id": ring.ring_id,
                        "topology": ring.topology,
                        "case_name": ring.case_name,
                        "provenance": ring.provenance,
                        "member_ad_ids": list(ring.member_ad_ids),
                        "shared_signal_types": list(ring.shared_signals.keys()),
                    }
                    for ring in self._episode.fraud_rings
                ],
            }

        return AuditorObservation(
            done=done,
            reward=self._auditor_reward_total,
            feedback=feedback or self._last_feedback["auditor"],
            phase=phase,
            full_episode_record=record,
            investigator_actions=list(self._investigator_log),
            fraudster_proposals=list(self._fraudster_log),
            investigation_data_seen=investigation_data_seen,
            pending_flags=[f.model_dump() for f in self._audit_flags],
        )

    # ------------------------------------------------------------------
    # State-machine helpers
    # ------------------------------------------------------------------

    def _guard_phase(self, expected: Phase, *, role: Role) -> None:
        if self._phase != expected:
            raise PermissionError(
                f"{role} cannot act during phase '{self._phase}' "
                f"(expected '{expected}')."
            )

    def _transition(self, *, to: Phase, note: str) -> None:
        if self._phase == to:
            return
        logger.debug("[referee] %s -> %s (%s)", self._phase, to, note)
        self._phase = to
        self._actions_this_turn = 0

    def _build_queue_summary(self) -> List[Dict[str, Any]]:
        assert self._episode is not None
        verdicts = self._investigator.verdicts
        proposal_ad_ids = set(self._proposal_slot_to_ad_id.values())
        slot_by_ad_id = {
            ad_id: slot for slot, ad_id in self._proposal_slot_to_ad_id.items()
        }

        out: List[Dict[str, Any]] = []
        for ad in self._episode.ads:
            v = verdicts.get(ad.ad_id)
            entry = {
                "ad_id": ad.ad_id,
                "ad_copy": ad.ad_copy,
                "category": ad.category,
                "status": (v["verdict"] if v else "pending"),
                "is_my_proposal": ad.ad_id in proposal_ad_ids,
            }
            if ad.ad_id in slot_by_ad_id:
                entry["slot_index"] = slot_by_ad_id[ad.ad_id]
            out.append(entry)
        return out

    def _build_verdict_history(self) -> List[Dict[str, Any]]:
        proposal_ad_ids = set(self._proposal_slot_to_ad_id.values())
        history: List[Dict[str, Any]] = []
        for entry in self._investigator_log:
            if entry.get("action_type") != "verdict":
                continue
            history.append(
                {
                    "ad_id": entry.get("ad_id"),
                    "verdict": entry.get("verdict"),
                    "confidence": entry.get("confidence"),
                    "rationale": entry.get("rationale"),
                    "was_my_proposal": entry.get("ad_id") in proposal_ad_ids,
                }
            )
        return history

    def _serialize_fraudster_action(

        self, action: FraudsterAction, reward: float

    ) -> Dict[str, Any]:
        payload: Dict[str, Any] = {
            "ts": time.time(),
            "phase": self._phase,
            "round_number": self._round_number,
            "action_type": action.action_type,
            "ad_copy": action.ad_copy,
            "category": action.category,
            "landing_page_blurb": action.landing_page_blurb,
            "targeting_summary": action.targeting_summary,
            "slot_index": action.slot_index,
            "new_ad_copy": action.new_ad_copy,
            "new_landing_page_blurb": action.new_landing_page_blurb,
            "rationale": action.rationale,
            "reward": reward,
            "ad_id": None,
        }

        # Enrich queue actions with the env-resolved ad context so the
        # auditor + downstream graders can key flags onto a real ad_id and
        # see the AD'S CURRENT STATE (not just the LLM's payload, which
        # for ``modify_pending_ad`` only carries the *delta* fields).
        if action.action_type == "propose_ad" and self._last_proposed_ad_id is not None:
            payload["ad_id"] = self._last_proposed_ad_id
            payload["slot_index"] = self._last_proposed_slot
            self._last_proposed_ad_id = None
            self._last_proposed_slot = None
        elif (
            action.action_type == "modify_pending_ad"
            and action.slot_index is not None
            and action.slot_index in self._proposal_slot_to_ad_id
        ):
            ad_id = self._proposal_slot_to_ad_id[action.slot_index]
            payload["ad_id"] = ad_id
            ad = self._find_episode_ad(ad_id)
            if ad is not None:
                # Always inject the ad's CURRENT state — the modify only
                # carries deltas, and post-modify the ad's authoritative
                # ``ad_copy`` / ``targeting_summary`` live on the
                # ``Ad`` object the env mutated in
                # ``_fraudster_modify_pending_ad``.
                payload.setdefault("category", ad.category)
                if not payload.get("ad_copy"):
                    payload["ad_copy"] = action.new_ad_copy or ad.ad_copy
                if not payload.get("targeting_summary"):
                    payload["targeting_summary"] = ad.targeting_summary
                if (
                    not payload.get("landing_page_blurb")
                    and self._episode is not None
                ):
                    lp = self._episode.landing_pages.get(ad_id)
                    if lp is not None:
                        payload["landing_page_blurb"] = (
                            action.new_landing_page_blurb
                            or lp.content_summary
                        )
        return payload

    def _find_episode_ad(self, ad_id: str) -> Optional[Ad]:
        if self._episode is None:
            return None
        for ad in self._episode.ads:
            if ad.ad_id == ad_id:
                return ad
        return None

    def _serialize_investigator_action(

        self, action: AdReviewAction, obs: AdReviewObservation

    ) -> Dict[str, Any]:
        return {
            "ts": time.time(),
            "phase": self._phase,
            "round_number": self._round_number,
            "action_type": action.action_type,
            "ad_id": action.ad_id,
            "investigation_target": action.investigation_target,
            "verdict": action.verdict,
            "confidence": action.confidence,
            "rationale": action.rationale,
            "linked_ad_id": action.linked_ad_id,
            "link_reason": action.link_reason,
            "reward": float(obs.reward or 0.0),
            "findings_excerpt": (obs.feedback or "")[:500],
        }

    # ------------------------------------------------------------------
    # Introspection helpers for the driver / clients
    # ------------------------------------------------------------------

    @property
    def phase(self) -> Phase:
        return self._phase

    @property
    def done(self) -> bool:
        return self._done

    @property
    def match_id(self) -> str:
        return self._match_id

    @property
    def episode(self) -> Optional[GeneratedEpisode]:
        return self._episode

    @property
    def registry(self) -> Optional[InvestigationToolRegistry]:
        return self._registry

    @property
    def investigator(self) -> InvestigatorEnvironment:
        return self._investigator

    def grader_score(self) -> Optional[float]:
        return self._grader_score