diff --git a/scripts/run_phase1.py b/scripts/run_phase1.py
index b709c82..6e399d8 100644
--- a/scripts/run_phase1.py
+++ b/scripts/run_phase1.py
@@ -37,6 +37,12 @@ def parse_args() -> argparse.Namespace:
         default=0.0,
         help="Phase 2.5: probabilità (0-1) che la mutazione invochi LLM mutator tier B",
     )
+    p.add_argument(
+        "--fees-eat-alpha-threshold",
+        type=float,
+        default=0.5,
+        help="Adversarial gate: kill se fees/gross_pnl > soglia (default 0.5, ablation 0.7)",
+    )
     return p.parse_args()
 
 
@@ -91,6 +97,7 @@ def main() -> None:
         n_trials_dsr=args.n_trials_dsr,
         db_path=settings.db_path,
         prompt_mutation_weight=args.prompt_mutation_weight,
+        fees_eat_alpha_threshold=args.fees_eat_alpha_threshold,
     )
 
     run_id = run_phase1(cfg, ohlcv=ohlcv, llm=llm)
diff --git a/src/multi_swarm/agents/adversarial.py b/src/multi_swarm/agents/adversarial.py
index 68f0512..0237585 100644
--- a/src/multi_swarm/agents/adversarial.py
+++ b/src/multi_swarm/agents/adversarial.py
@@ -59,8 +59,13 @@ class AdversarialReport:
 class AdversarialAgent:
     """Agente hand-crafted che applica check euristici a una strategia."""
 
-    def __init__(self, fees_bp: float = 5.0) -> None:
+    def __init__(
+        self,
+        fees_bp: float = 5.0,
+        fees_eat_alpha_threshold: float = 0.5,
+    ) -> None:
         self._engine = BacktestEngine(fees_bp=fees_bp)
+        self._fees_eat_alpha_threshold = fees_eat_alpha_threshold
 
     def review(self, strategy: Strategy, ohlcv: pd.DataFrame) -> AdversarialReport:
         signal_fn = compile_strategy(strategy)
@@ -163,7 +168,7 @@ class AdversarialAgent:
         # Se gross_pnl <= 0 il check non si applica (gia' perdente).
         gross_pnl = sum(t.gross_pnl for t in result.trades)
         total_fees = sum(t.fees for t in result.trades)
-        if gross_pnl > 0 and total_fees / gross_pnl > 0.5:
+        if gross_pnl > 0 and total_fees / gross_pnl > self._fees_eat_alpha_threshold:
             report.findings.append(
                 Finding(
                     name="fees_eat_alpha",
diff --git a/src/multi_swarm/ga/loop.py b/src/multi_swarm/ga/loop.py
index 9397783..893fe91 100644
--- a/src/multi_swarm/ga/loop.py
+++ b/src/multi_swarm/ga/loop.py
@@ -25,12 +25,16 @@ def next_generation(
     cfg: GAConfig,
     rng: random.Random,
     llm: Any | None = None,
+    cost_tracker: Any | None = None,
+    repo: Any | None = None,
+    run_id: str | None = None,
 ) -> list[HypothesisAgentGenome]:
     """Costruisce la prossima generazione: elitismo + tournament + crossover/mutate.
 
     Quando ``cfg.prompt_mutation_weight > 0`` e ``llm`` è fornito, la mutazione
     invoca ``weighted_random_mutate`` che con quella probabilità usa
-    ``mutate_prompt_llm`` (Phase 2.5).
+    ``mutate_prompt_llm`` (Phase 2.5). Cost tracker/repo/run_id si propagano
+    per registrare ``call_kind="mutation"`` sulle call mutator.
     """
     new_pop: list[HypothesisAgentGenome] = list(
         elite_select(population, fitnesses, cfg.elite_k)
@@ -44,7 +48,12 @@ def next_generation(
         else:
             parent = tournament_select(population, fitnesses, cfg.tournament_k, rng)
             child = weighted_random_mutate(
-                parent, rng, llm=llm, prompt_mutation_weight=cfg.prompt_mutation_weight
+                parent, rng,
+                llm=llm,
+                prompt_mutation_weight=cfg.prompt_mutation_weight,
+                cost_tracker=cost_tracker,
+                repo=repo,
+                run_id=run_id,
             )
         new_pop.append(child)
 
diff --git a/src/multi_swarm/genome/mutation.py b/src/multi_swarm/genome/mutation.py
index cef606b..1fdd616 100644
--- a/src/multi_swarm/genome/mutation.py
+++ b/src/multi_swarm/genome/mutation.py
@@ -82,16 +82,24 @@ def weighted_random_mutate(
     rng: random.Random,
     llm: Any | None = None,
     prompt_mutation_weight: float = 0.0,
+    cost_tracker: Any | None = None,
+    repo: Any | None = None,
+    run_id: str | None = None,
 ) -> HypothesisAgentGenome:
     """Dispatcher pesato fra mutate_prompt_llm e random_mutate scalare.
 
     Con probabilità ``prompt_mutation_weight`` invoca ``mutate_prompt_llm``,
     altrimenti ``random_mutate``. Se ``llm`` è ``None`` o il peso è 0,
     è equivalente a ``random_mutate`` (backward-compat).
+
+    Se ``cost_tracker``, ``repo`` e ``run_id`` sono forniti, vengono propagati a
+    ``mutate_prompt_llm`` per tracciare la call con ``call_kind="mutation"``.
     """
     if llm is not None and prompt_mutation_weight > 0 and rng.random() < prompt_mutation_weight:
         # Import inline per evitare ciclo: mutation_prompt_llm importa da mutation.
         from .mutation_prompt_llm import mutate_prompt_llm
 
-        return mutate_prompt_llm(g, llm, rng)
+        return mutate_prompt_llm(
+            g, llm, rng, cost_tracker=cost_tracker, repo=repo, run_id=run_id
+        )
     return random_mutate(g, rng)
diff --git a/src/multi_swarm/genome/mutation_prompt_llm.py b/src/multi_swarm/genome/mutation_prompt_llm.py
index 20213fc..8d573c0 100644
--- a/src/multi_swarm/genome/mutation_prompt_llm.py
+++ b/src/multi_swarm/genome/mutation_prompt_llm.py
@@ -130,6 +130,9 @@ def mutate_prompt_llm(
     rng: random.Random,
     mutator_tier: ModelTier = ModelTier.B,
     max_tokens: int = 2000,
+    cost_tracker: Any | None = None,
+    repo: Any | None = None,
+    run_id: str | None = None,
 ) -> HypothesisAgentGenome:
     """Operatore di mutazione prompt-level via LLM mutator.
 
@@ -137,6 +140,9 @@ def mutate_prompt_llm(
     LLM tier B per ottenere il prompt mutato, valida l'output. Su validation
     fail (output troppo corto, non-strategia, troppo simile al parent),
     fallback silenzioso a ``random_mutate``.
+
+    Se ``cost_tracker``, ``repo`` e ``run_id`` sono forniti, la chiamata mutator
+    viene registrata con ``call_kind="mutation"`` per audit budget.
     """
     instruction_key = rng.choice(list(MUTATION_INSTRUCTIONS))
     instruction = MUTATION_INSTRUCTIONS[instruction_key]
@@ -160,6 +166,28 @@ def mutate_prompt_llm(
     except Exception:
         return random_mutate(g, rng)
 
+    # Cost tracking call_kind="mutation" se sink fornito.
+    if cost_tracker is not None and repo is not None and run_id is not None:
+        in_tok = getattr(result, "input_tokens", 0)
+        out_tok = getattr(result, "output_tokens", 0)
+        cr = cost_tracker.record(
+            input_tokens=in_tok,
+            output_tokens=out_tok,
+            tier=mutator_tier,
+            run_id=run_id,
+            agent_id=g.id,
+            call_kind="mutation",
+        )
+        repo.save_cost_record(
+            run_id=run_id,
+            agent_id=g.id,
+            tier=mutator_tier.value,
+            input_tokens=in_tok,
+            output_tokens=out_tok,
+            cost_usd=cr.cost_usd,
+            call_kind="mutation",
+        )
+
     new_prompt = _extract_prompt(getattr(result, "text", ""))
     if not is_valid_prompt(new_prompt, g.system_prompt):
         return random_mutate(g, rng)
diff --git a/src/multi_swarm/llm/cost_tracker.py b/src/multi_swarm/llm/cost_tracker.py
index 9db7e54..42546d7 100644
--- a/src/multi_swarm/llm/cost_tracker.py
+++ b/src/multi_swarm/llm/cost_tracker.py
@@ -30,6 +30,7 @@ class CostRecord:
     input_tokens: int
     output_tokens: int
     cost_usd: float
+    call_kind: str = "hypothesis"  # "hypothesis" | "mutation"
 
 
 @dataclass
@@ -43,6 +44,7 @@ class CostTracker:
         tier: ModelTier,
         run_id: str,
         agent_id: str,
+        call_kind: str = "hypothesis",
     ) -> CostRecord:
         cost = estimate_cost(input_tokens, output_tokens, tier)
         rec = CostRecord(
@@ -53,6 +55,7 @@ class CostTracker:
             input_tokens=input_tokens,
             output_tokens=output_tokens,
             cost_usd=cost,
+            call_kind=call_kind,
         )
         self.records.append(rec)
         return rec
@@ -61,16 +64,25 @@ class CostTracker:
         by_tier: dict[str, dict[str, float]] = defaultdict(
             lambda: {"calls": 0, "input_tokens": 0, "output_tokens": 0, "cost_usd": 0.0}
         )
+        by_call_kind: dict[str, dict[str, float]] = defaultdict(
+            lambda: {"calls": 0, "input_tokens": 0, "output_tokens": 0, "cost_usd": 0.0}
+        )
         for r in self.records:
             t = r.tier.value
             by_tier[t]["calls"] += 1
             by_tier[t]["input_tokens"] += r.input_tokens
             by_tier[t]["output_tokens"] += r.output_tokens
             by_tier[t]["cost_usd"] += r.cost_usd
+            ck = r.call_kind
+            by_call_kind[ck]["calls"] += 1
+            by_call_kind[ck]["input_tokens"] += r.input_tokens
+            by_call_kind[ck]["output_tokens"] += r.output_tokens
+            by_call_kind[ck]["cost_usd"] += r.cost_usd
         return {
             "calls": len(self.records),
             "input_tokens": sum(r.input_tokens for r in self.records),
             "output_tokens": sum(r.output_tokens for r in self.records),
             "cost_usd": sum(r.cost_usd for r in self.records),
             "by_tier": dict(by_tier),
+            "by_call_kind": dict(by_call_kind),
         }
diff --git a/src/multi_swarm/orchestrator/run.py b/src/multi_swarm/orchestrator/run.py
index a915c94..c6afca2 100644
--- a/src/multi_swarm/orchestrator/run.py
+++ b/src/multi_swarm/orchestrator/run.py
@@ -50,6 +50,7 @@ class RunConfig:
     n_trials_dsr: int = 50
     db_path: Path = field(default_factory=lambda: Path("./runs.db"))
     prompt_mutation_weight: float = 0.0  # Phase 2.5: opt-in LLM mutator
+    fees_eat_alpha_threshold: float = 0.5  # adversarial gate, allenta verso 0.7-0.8
 
 
 def run_phase1(
@@ -78,7 +79,10 @@ def run_phase1(
     falsification_agent = FalsificationAgent(
         fees_bp=cfg.fees_bp, n_trials_dsr=cfg.n_trials_dsr
     )
-    adversarial_agent = AdversarialAgent(fees_bp=cfg.fees_bp)
+    adversarial_agent = AdversarialAgent(
+        fees_bp=cfg.fees_bp,
+        fees_eat_alpha_threshold=cfg.fees_eat_alpha_threshold,
+    )
     cost_tracker = CostTracker()
 
     population = build_initial_population(
@@ -178,6 +182,9 @@ def run_phase1(
                 population = next_generation(
                     population, fitnesses, ga_cfg, rng,
                     llm=llm if cfg.prompt_mutation_weight > 0 else None,
+                    cost_tracker=cost_tracker if cfg.prompt_mutation_weight > 0 else None,
+                    repo=repo if cfg.prompt_mutation_weight > 0 else None,
+                    run_id=run_id if cfg.prompt_mutation_weight > 0 else None,
                 )
 
         repo.complete_run(
diff --git a/src/multi_swarm/persistence/repository.py b/src/multi_swarm/persistence/repository.py
index 4e46c38..09f4b39 100644
--- a/src/multi_swarm/persistence/repository.py
+++ b/src/multi_swarm/persistence/repository.py
@@ -26,6 +26,14 @@ class Repository:
         self.db_path.parent.mkdir(parents=True, exist_ok=True)
         with self._conn() as conn:
             conn.executescript(SCHEMA_SQL)
+            # Migration soft per DB pre-Task 6: aggiunge call_kind se manca.
+            try:
+                conn.execute(
+                    "ALTER TABLE cost_records ADD COLUMN call_kind "
+                    "TEXT NOT NULL DEFAULT 'hypothesis'"
+                )
+            except sqlite3.OperationalError:
+                pass  # colonna già presente
 
     @staticmethod
     def _now() -> str:
@@ -184,12 +192,13 @@ class Repository:
         input_tokens: int,
         output_tokens: int,
         cost_usd: float,
+        call_kind: str = "hypothesis",
     ) -> None:
         with self._conn() as conn:
             conn.execute(
                 """INSERT INTO cost_records
-                   (run_id, agent_id, ts, tier, input_tokens, output_tokens, cost_usd)
-                   VALUES (?,?,?,?,?,?,?)""",
+                   (run_id, agent_id, ts, tier, input_tokens, output_tokens, cost_usd, call_kind)
+                   VALUES (?,?,?,?,?,?,?,?)""",
                 (
                     run_id,
                     agent_id,
@@ -198,6 +207,7 @@ class Repository:
                     input_tokens,
                     output_tokens,
                     cost_usd,
+                    call_kind,
                 ),
             )
 
diff --git a/src/multi_swarm/persistence/schema.py b/src/multi_swarm/persistence/schema.py
index 5b15054..c66456f 100644
--- a/src/multi_swarm/persistence/schema.py
+++ b/src/multi_swarm/persistence/schema.py
@@ -58,6 +58,7 @@ CREATE TABLE IF NOT EXISTS cost_records (
     input_tokens INTEGER NOT NULL,
     output_tokens INTEGER NOT NULL,
     cost_usd REAL NOT NULL,
+    call_kind TEXT NOT NULL DEFAULT 'hypothesis',
     FOREIGN KEY (run_id) REFERENCES runs(id)
 );
 
diff --git a/tests/unit/test_cost_tracker.py b/tests/unit/test_cost_tracker.py
index 08733d3..89fb69e 100644
--- a/tests/unit/test_cost_tracker.py
+++ b/tests/unit/test_cost_tracker.py
@@ -61,3 +61,28 @@ def test_tracker_summary_contains_all_five_tiers():
     for tier_letter in ("S", "A", "B", "C", "D"):
         assert tier_letter in summary["by_tier"]
         assert summary["by_tier"][tier_letter]["calls"] == 1
+
+
+def test_tracker_default_call_kind_is_hypothesis():
+    t = CostTracker()
+    rec = t.record(input_tokens=10, output_tokens=10, tier=ModelTier.C, run_id="r", agent_id="a")
+    assert rec.call_kind == "hypothesis"
+    summary = t.summary()
+    assert "hypothesis" in summary["by_call_kind"]
+    assert summary["by_call_kind"]["hypothesis"]["calls"] == 1
+    assert "mutation" not in summary["by_call_kind"]
+
+
+def test_tracker_by_call_kind_breakdown():
+    t = CostTracker()
+    t.record(input_tokens=100, output_tokens=200, tier=ModelTier.C, run_id="r", agent_id="a")
+    t.record(input_tokens=100, output_tokens=200, tier=ModelTier.C, run_id="r", agent_id="a")
+    t.record(
+        input_tokens=50, output_tokens=80, tier=ModelTier.B,
+        run_id="r", agent_id="parent-x", call_kind="mutation",
+    )
+    summary = t.summary()
+    assert summary["by_call_kind"]["hypothesis"]["calls"] == 2
+    assert summary["by_call_kind"]["mutation"]["calls"] == 1
+    assert summary["by_call_kind"]["mutation"]["input_tokens"] == 50
+    assert summary["by_call_kind"]["mutation"]["output_tokens"] == 80
diff --git a/tests/unit/test_mutation_prompt_llm.py b/tests/unit/test_mutation_prompt_llm.py
index bbb5784..1a0eccd 100644
--- a/tests/unit/test_mutation_prompt_llm.py
+++ b/tests/unit/test_mutation_prompt_llm.py
@@ -161,6 +161,69 @@ def test_mutate_prompt_llm_falls_back_on_llm_exception() -> None:
     assert child.generation == parent.generation + 1
 
 
+def test_mutate_prompt_llm_logs_mutation_cost_when_sink_provided() -> None:
+    """Quando cost_tracker+repo+run_id sono forniti, la call mutator viene loggata
+    con call_kind='mutation' sia in memoria sia nel repo."""
+    mutated = (
+        "Strategia RSI 1h evolved. Entry long quando RSI(14) < 28 e close > "
+        "SMA(50). Exit short quando RSI(14) > 72."
+    )
+
+    class _R:
+        text = f"<prompt>{mutated}</prompt>"
+        input_tokens = 350
+        output_tokens = 140
+
+    class _FakeLLMCosted:
+        def complete(self, genome, system, user, max_tokens=2000):
+            return _R()
+
+    tracker_calls = []
+    repo_calls = []
+
+    class _FakeTracker:
+        def record(self, **kw):
+            tracker_calls.append(kw)
+            from types import SimpleNamespace
+            return SimpleNamespace(cost_usd=0.0042)
+
+    class _FakeRepo:
+        def save_cost_record(self, **kw):
+            repo_calls.append(kw)
+
+    parent = _make_genome()
+    child = mutate_prompt_llm(
+        parent, _FakeLLMCosted(), random.Random(0),
+        cost_tracker=_FakeTracker(), repo=_FakeRepo(), run_id="run-xyz",
+    )
+    assert child.system_prompt == mutated
+    assert len(tracker_calls) == 1
+    assert tracker_calls[0]["call_kind"] == "mutation"
+    assert tracker_calls[0]["tier"] == ModelTier.B
+    assert tracker_calls[0]["run_id"] == "run-xyz"
+    assert tracker_calls[0]["agent_id"] == parent.id
+    assert tracker_calls[0]["input_tokens"] == 350
+    assert tracker_calls[0]["output_tokens"] == 140
+
+    assert len(repo_calls) == 1
+    assert repo_calls[0]["call_kind"] == "mutation"
+    assert repo_calls[0]["tier"] == "B"
+    assert repo_calls[0]["cost_usd"] == 0.0042
+
+
+def test_mutate_prompt_llm_no_logging_without_sink() -> None:
+    """Senza cost_tracker+repo+run_id → niente logging cost (backward compat)."""
+    mutated = (
+        "Strategia RSI 1h evoluta. Entry long quando RSI(14) < 25 e close > "
+        "SMA(60). Exit short quando RSI(14) > 75 e ATR rising."
+    )
+    llm = _FakeLLM(response_text=f"<prompt>{mutated}</prompt>")
+    parent = _make_genome()
+    # Non solleva (anche se 0 sink forniti)
+    child = mutate_prompt_llm(parent, llm, random.Random(0))
+    assert child.system_prompt == mutated
+
+
 def test_mutate_prompt_llm_picks_one_of_six_instructions() -> None:
     """Verifica che il system message dell'LLM includa una delle 6 istruzioni."""
     mutated = (