diff --git a/ml/config/scope.py b/ml/config/scope.py
index 2dcd01a..3a46b2c 100644
--- a/ml/config/scope.py
+++ b/ml/config/scope.py
@@ -256,3 +256,49 @@ class TrainingConfig:
     log_every: int = 100               # Log every N batches
 
 TRAINING_CONFIG = TrainingConfig()
+
+
+# ══════════════════════════════════════════════════════════
+# Distillation Loop Defaults (Phase 4)
+# ══════════════════════════════════════════════════════════
+
+@dataclass
+class DistillationDefaults:
+    """Default hyperparameters for the closed-loop distillation pipeline.
+
+    These are consumed by ml.training.distillation_loop.DistillationConfig
+    when no explicit override is provided.
+    """
+    max_iterations: int = 10
+    convergence_window: int = 3
+    convergence_threshold: float = 0.01
+
+    # PPO self-play per generation
+    ppo_iterations: int = 50
+    ppo_episodes_per_iter: int = 64
+    ppo_lr: float = 3e-4
+    ppo_clip_epsilon: float = 0.2
+    ppo_entropy_coeff: float = 0.01
+    ppo_eval_episodes: int = 100
+
+    # Dataset mixing
+    forge_weight: float = 1.0
+    ppo_weight: float = 0.5
+    min_reward_threshold: float = 0.0
+
+    # Quality gate thresholds
+    min_forge_accuracy: float = 0.35
+    max_accuracy_drop: float = 0.03
+    min_ppo_win_rate: float = 0.30
+
+    # Retry behaviour on gate failure
+    max_retries_per_generation: int = 2
+    retry_lr_factor: float = 0.5
+    retry_entropy_boost: float = 0.005
+
+    # Output paths
+    results_dir: str = "data/results"
+    history_dir: str = "data/results/distillation-history"
+
+
+DISTILLATION_DEFAULTS = DistillationDefaults()
diff --git a/ml/training/distillation_loop.py b/ml/training/distillation_loop.py
new file mode 100644
index 0000000..e9894c1
--- /dev/null
+++ b/ml/training/distillation_loop.py
@@ -0,0 +1,817 @@
+"""
+Commander AI Lab — Distillation Loop Orchestrator
+═══════════════════════════════════════════════════
+
+Phase 4 (Issue #68): Automates the full closed-loop distillation cycle:
+
+    1. Supervised train on current dataset (Forge + any existing PPO data)
+    2. Run N episodes of PPO self-play using the supervised model as starting policy
+    3. Export winning PPO decisions to JSONL
+    4. Quality gate check
+    5. If passed → merge into dataset and repeat from step 1
+    6. If failed → discard PPO batch, adjust hyperparameters, retry
+
+Each iteration is a "generation" — data and models are tagged with generation
+number for traceability.
+
+Convergence detection:
+  - Stops if win rate plateaus across `convergence_window` generations
+  - Hard stop at `max_iterations`
+
+Ref: docs/CLOSED-LOOP-DISTILLATION.md — Phase 4
+Issue: #68
+"""
+
+import json
+import logging
+import os
+import shutil
+import sys
+import time
+from dataclasses import dataclass, field
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Dict, List, Optional
+
+import numpy as np
+
+project_root = str(Path(__file__).parent.parent.parent)
+if project_root not in sys.path:
+    sys.path.insert(0, project_root)
+
+from ml.config.scope import (
+    NUM_ACTIONS, STATE_DIMS, TRAINING_CONFIG,
+)
+from ml.data.quality_gate import QualityGate, QualityGateConfig, GateVerdict
+from ml.training.decision_exporter import DecisionExporter, ExporterConfig
+
+logger = logging.getLogger("ml.distillation")
+
+
+# ═══════════════════════════════════════════════════════════
+# Configuration
+# ═══════════════════════════════════════════════════════════
+
+@dataclass
+class DistillationConfig:
+    """Configuration for the distillation loop orchestrator."""
+
+    # --- Loop control ---
+    max_iterations: int = 10
+    convergence_window: int = 3       # Check last N generations for plateau
+    convergence_threshold: float = 0.01  # Min win-rate improvement to not plateau
+
+    # --- Paths ---
+    results_dir: str = "data/results"
+    models_dir: str = "ml/models"
+    checkpoint_dir: str = "ml/models/checkpoints"
+    history_dir: str = "data/results/distillation-history"
+
+    # --- Supervised training ---
+    supervised_epochs: int = 30
+    supervised_lr: float = 1e-3
+    supervised_batch_size: int = 64
+    supervised_patience: int = 5
+
+    # --- PPO self-play ---
+    ppo_iterations: int = 50
+    ppo_episodes_per_iter: int = 64
+    ppo_batch_size: int = 256
+    ppo_lr: float = 3e-4
+    ppo_clip_epsilon: float = 0.2
+    ppo_entropy_coeff: float = 0.01
+    ppo_eval_episodes: int = 100
+    opponent: str = "heuristic"
+    playstyle: str = "midrange"
+
+    # --- Dataset building ---
+    forge_weight: float = 1.0
+    ppo_weight: float = 0.5
+    min_reward_threshold: float = 0.0
+
+    # --- Quality gate ---
+    min_forge_accuracy: float = 0.35
+    max_accuracy_drop: float = 0.03
+    min_ppo_win_rate: float = 0.30
+
+    # --- Retry on gate failure ---
+    max_retries_per_generation: int = 2
+    retry_lr_factor: float = 0.5       # Halve PPO LR on retry
+    retry_entropy_boost: float = 0.005  # Increase entropy coeff on retry
+
+
+# ═══════════════════════════════════════════════════════════
+# Generation metadata
+# ═══════════════════════════════════════════════════════════
+
+@dataclass
+class GenerationRecord:
+    """Tracks metadata for a single distillation generation."""
+    generation: int
+    started_at: str = ""
+    completed_at: str = ""
+    status: str = "pending"  # pending | running | passed | failed | skipped
+
+    # Supervised training results
+    supervised_val_acc: float = 0.0
+    supervised_best_epoch: int = 0
+    supervised_checkpoint: str = ""
+
+    # PPO self-play results
+    ppo_win_rate: float = 0.0
+    ppo_best_win_rate: float = 0.0
+    ppo_episodes: int = 0
+    ppo_decisions_exported: int = 0
+    ppo_export_path: str = ""
+
+    # Quality gate
+    gate_accepted: bool = False
+    gate_reason: str = ""
+    baseline_accuracy: float = 0.0
+    post_merge_accuracy: float = 0.0
+
+    # Dataset stats
+    dataset_size: int = 0
+    forge_samples: int = 0
+    ppo_samples: int = 0
+
+    retries: int = 0
+    error: str = ""
+
+    def to_dict(self) -> dict:
+        return {k: v for k, v in self.__dict__.items()}
+
+
+# ═══════════════════════════════════════════════════════════
+# Distillation Loop Orchestrator
+# ═══════════════════════════════════════════════════════════
+
+class DistillationLoop:
+    """
+    Orchestrates the full closed-loop distillation pipeline.
+
+    Each "generation" runs the complete cycle:
+      supervised train → PPO self-play → export → quality gate → merge
+
+    The loop tracks convergence by monitoring PPO win rate across
+    generations and stops when improvement plateaus or max_iterations
+    is reached.
+
+    Usage::
+
+        config = DistillationConfig(max_iterations=5, ppo_iterations=30)
+        loop = DistillationLoop(config)
+        summary = loop.run()
+    """
+
+    def __init__(self, config: DistillationConfig = None):
+        self.config = config or DistillationConfig()
+        self.generations: List[GenerationRecord] = []
+        self.quality_gate = QualityGate(QualityGateConfig(
+            min_forge_accuracy=self.config.min_forge_accuracy,
+            max_accuracy_drop=self.config.max_accuracy_drop,
+            min_ppo_win_rate=self.config.min_ppo_win_rate,
+        ))
+        self._baseline_accuracy: Optional[float] = None
+        self._device: Optional[str] = None
+        self._stopped = False
+
+        # Ensure output directories exist
+        os.makedirs(self.config.history_dir, exist_ok=True)
+        os.makedirs(self.config.checkpoint_dir, exist_ok=True)
+        os.makedirs(self.config.results_dir, exist_ok=True)
+
+    # ------------------------------------------------------------------
+    # Public API
+    # ------------------------------------------------------------------
+
+    def run(self, progress_callback=None) -> Dict:
+        """
+        Run the full distillation loop.
+
+        Args:
+            progress_callback: Optional callable(generation, record) for
+                               progress reporting (e.g. to a web UI).
+
+        Returns:
+            Summary dict with per-generation metrics and convergence info.
+        """
+        cfg = self.config
+        self._device = self._detect_device()
+
+        logger.info("=" * 65)
+        logger.info("  Commander AI Lab — Distillation Loop")
+        logger.info("=" * 65)
+        logger.info("  Max iterations:     %d", cfg.max_iterations)
+        logger.info("  Convergence window: %d", cfg.convergence_window)
+        logger.info("  PPO iters/gen:      %d", cfg.ppo_iterations)
+        logger.info("  PPO episodes/iter:  %d", cfg.ppo_episodes_per_iter)
+        logger.info("  Supervised epochs:  %d", cfg.supervised_epochs)
+        logger.info("  Device:             %s", self._device)
+        logger.info("  Results dir:        %s", cfg.results_dir)
+        logger.info("=" * 65)
+
+        loop_start = time.time()
+
+        for gen_num in range(1, cfg.max_iterations + 1):
+            if self._stopped:
+                logger.info("Loop stopped by external signal.")
+                break
+
+            logger.info("")
+            logger.info("─" * 65)
+            logger.info("  GENERATION %d / %d", gen_num, cfg.max_iterations)
+            logger.info("─" * 65)
+
+            record = self._run_generation(gen_num)
+            self.generations.append(record)
+
+            # Save generation history to disk after each round
+            self._save_history()
+
+            if progress_callback:
+                progress_callback(gen_num, record)
+
+            # Check convergence
+            if self._check_convergence():
+                logger.info(
+                    "Convergence detected — win rate plateaued over "
+                    "last %d generations. Stopping.",
+                    cfg.convergence_window,
+                )
+                break
+
+        total_time = time.time() - loop_start
+
+        summary = self._build_summary(total_time)
+        self._save_summary(summary)
+
+        logger.info("")
+        logger.info("=" * 65)
+        logger.info("  Distillation Loop Complete")
+        logger.info("=" * 65)
+        logger.info("  Generations run:  %d", summary["generations_run"])
+        logger.info("  Generations passed: %d", summary["generations_passed"])
+        logger.info("  Best win rate:    %.1f%%", summary["best_win_rate"] * 100)
+        logger.info("  Converged:        %s", summary["converged"])
+        logger.info("  Total time:       %.1f s", total_time)
+        logger.info("=" * 65)
+
+        return summary
+
+    def stop(self):
+        """Signal the loop to stop after the current generation."""
+        self._stopped = True
+        logger.info("Stop signal received — will halt after current generation.")
+
+    # ------------------------------------------------------------------
+    # Single generation execution
+    # ------------------------------------------------------------------
+
+    def _run_generation(self, gen_num: int) -> GenerationRecord:
+        """Execute a single distillation generation (steps 1-6)."""
+        record = GenerationRecord(
+            generation=gen_num,
+            started_at=datetime.now(timezone.utc).isoformat(),
+            status="running",
+        )
+
+        cfg = self.config
+        gen_tag = f"gen-{gen_num:03d}"
+        gen_checkpoint_dir = os.path.join(cfg.checkpoint_dir, gen_tag)
+        os.makedirs(gen_checkpoint_dir, exist_ok=True)
+
+        try:
+            # ─── Step 1: Supervised Train ───────────────────────────
+            logger.info("  [Step 1] Supervised training on current dataset...")
+            sup_result = self._supervised_train(gen_checkpoint_dir, gen_tag)
+
+            if sup_result is None:
+                record.status = "failed"
+                record.error = "Supervised training failed — no dataset found"
+                record.completed_at = datetime.now(timezone.utc).isoformat()
+                return record
+
+            record.supervised_val_acc = sup_result["best_val_acc"]
+            record.supervised_best_epoch = sup_result["best_epoch"]
+            record.supervised_checkpoint = sup_result["checkpoint_path"]
+
+            # Set baseline accuracy on first generation
+            if self._baseline_accuracy is None:
+                self._baseline_accuracy = sup_result["best_val_acc"]
+                logger.info(
+                    "  Baseline accuracy set: %.3f (generation 1)",
+                    self._baseline_accuracy,
+                )
+
+            # ─── Step 2-3: PPO Self-Play + Export ───────────────────
+            retries = 0
+            ppo_lr = cfg.ppo_lr
+            entropy_coeff = cfg.ppo_entropy_coeff
+            gate_passed = False
+
+            while retries <= cfg.max_retries_per_generation and not gate_passed:
+                if retries > 0:
+                    logger.info(
+                        "  [Retry %d/%d] Adjusting hyperparameters: "
+                        "lr=%.2e → %.2e, entropy=%.4f → %.4f",
+                        retries, cfg.max_retries_per_generation,
+                        ppo_lr, ppo_lr * cfg.retry_lr_factor,
+                        entropy_coeff, entropy_coeff + cfg.retry_entropy_boost,
+                    )
+                    ppo_lr *= cfg.retry_lr_factor
+                    entropy_coeff += cfg.retry_entropy_boost
+
+                logger.info(
+                    "  [Step 2] PPO self-play (%d iters × %d episodes)...",
+                    cfg.ppo_iterations, cfg.ppo_episodes_per_iter,
+                )
+                ppo_result, exporter = self._ppo_self_play(
+                    supervised_checkpoint=sup_result["checkpoint_path"],
+                    gen_tag=gen_tag,
+                    gen_checkpoint_dir=gen_checkpoint_dir,
+                    learning_rate=ppo_lr,
+                    entropy_coeff=entropy_coeff,
+                )
+
+                record.ppo_win_rate = ppo_result["final_win_rate"]
+                record.ppo_best_win_rate = ppo_result["best_win_rate"]
+                record.ppo_episodes = (
+                    cfg.ppo_iterations * cfg.ppo_episodes_per_iter
+                )
+
+                logger.info(
+                    "  [Step 3] Exporting PPO decisions (win rate: %.1f%%)...",
+                    ppo_result["best_win_rate"] * 100,
+                )
+                export_path = exporter.flush()
+                record.ppo_decisions_exported = exporter.stats["exported_decisions"]
+                record.ppo_export_path = export_path or ""
+
+                # ─── Step 4: Quality Gate ───────────────────────────
+                logger.info("  [Step 4] Quality gate check...")
+                verdict = self._quality_gate_check(
+                    ppo_win_rate=ppo_result["best_win_rate"],
+                    total_episodes=record.ppo_episodes,
+                    exporter=exporter,
+                )
+
+                if verdict.accepted:
+                    gate_passed = True
+                    record.gate_accepted = True
+                    record.gate_reason = verdict.reason
+                    logger.info("  QUALITY GATE: PASSED — %s", verdict.reason)
+                else:
+                    retries += 1
+                    record.retries = retries
+                    logger.warning(
+                        "  QUALITY GATE: FAILED — %s", verdict.reason,
+                    )
+
+                    if retries > cfg.max_retries_per_generation:
+                        # ─── Step 6: Discard PPO batch ──────────────
+                        logger.warning(
+                            "  [Step 6] Max retries exceeded — "
+                            "discarding PPO batch for generation %d.",
+                            gen_num,
+                        )
+                        if export_path and os.path.exists(export_path):
+                            os.remove(export_path)
+                            logger.info(
+                                "  Deleted rejected PPO data: %s", export_path
+                            )
+                        record.gate_accepted = False
+                        record.gate_reason = (
+                            f"Failed after {retries - 1} retries: "
+                            f"{verdict.reason}"
+                        )
+
+            # ─── Step 5: Merge into dataset (if passed) ─────────────
+            if gate_passed:
+                logger.info(
+                    "  [Step 5] PPO data accepted — will be included "
+                    "in next generation's dataset build."
+                )
+                record.status = "passed"
+            else:
+                record.status = "failed"
+
+        except Exception as e:
+            logger.exception("  Generation %d failed with error: %s", gen_num, e)
+            record.status = "failed"
+            record.error = str(e)
+
+        record.completed_at = datetime.now(timezone.utc).isoformat()
+        return record
+
+    # ------------------------------------------------------------------
+    # Step 1: Supervised Training
+    # ------------------------------------------------------------------
+
+    def _supervised_train(
+        self,
+        gen_checkpoint_dir: str,
+        gen_tag: str,
+    ) -> Optional[Dict]:
+        """
+        Build dataset from all available data and train supervised model.
+
+        Returns training summary dict or None on failure.
+        """
+        try:
+            import torch
+        except ImportError:
+            raise RuntimeError("PyTorch required for distillation loop")
+
+        cfg = self.config
+
+        # Build dataset (picks up both Forge + any PPO JSONL files in results_dir)
+        from ml.data.dataset_builder import build_dataset, split_dataset, save_dataset
+
+        try:
+            dataset = build_dataset(
+                results_dir=cfg.results_dir,
+                max_samples=None,
+                source_weights={
+                    "forge": cfg.forge_weight,
+                    "ppo": cfg.ppo_weight,
+                },
+                min_reward_threshold=cfg.min_reward_threshold,
+            )
+        except RuntimeError as e:
+            logger.warning("Dataset build failed: %s", e)
+            return None
+
+        if not dataset or len(dataset.get("states", [])) == 0:
+            logger.warning("No training data available.")
+            return None
+
+        # Split
+        train_data, val_data, test_data = split_dataset(dataset)
+
+        # Save splits (overwrite each generation — latest always at standard path)
+        data_dir = cfg.models_dir
+        os.makedirs(data_dir, exist_ok=True)
+        save_dataset(train_data, os.path.join(data_dir, "dataset-train.npz"))
+        save_dataset(val_data, os.path.join(data_dir, "dataset-val.npz"))
+        save_dataset(test_data, os.path.join(data_dir, "dataset-test.npz"))
+
+        # Create model
+        from ml.training.policy_network import PolicyNetwork
+        actual_dim = train_data["states"].shape[1]
+        model = PolicyNetwork(input_dim=actual_dim)
+
+        # Train
+        from ml.training.trainer import SupervisedTrainer, get_best_device
+        device = self._device or get_best_device()
+        trainer = SupervisedTrainer(
+            model=model,
+            device=device,
+            learning_rate=cfg.supervised_lr,
+            batch_size=cfg.supervised_batch_size,
+            epochs=cfg.supervised_epochs,
+            patience=cfg.supervised_patience,
+            checkpoint_dir=gen_checkpoint_dir,
+        )
+
+        summary = trainer.train(
+            train_states=train_data["states"],
+            train_labels=train_data["labels"],
+            val_states=val_data["states"],
+            val_labels=val_data["labels"],
+        )
+
+        # Also copy best checkpoint to the standard location
+        best_src = os.path.join(gen_checkpoint_dir, "best_policy.pt")
+        best_dst = os.path.join(cfg.checkpoint_dir, "best_policy.pt")
+        if os.path.exists(best_src):
+            shutil.copy2(best_src, best_dst)
+
+        return summary
+
+    # ------------------------------------------------------------------
+    # Steps 2-3: PPO Self-Play + Decision Export
+    # ------------------------------------------------------------------
+
+    def _ppo_self_play(
+        self,
+        supervised_checkpoint: str,
+        gen_tag: str,
+        gen_checkpoint_dir: str,
+        learning_rate: float = None,
+        entropy_coeff: float = None,
+    ) -> tuple:
+        """
+        Run PPO self-play initialized from the supervised checkpoint.
+
+        Returns (ppo_summary, exporter) tuple.
+        """
+        cfg = self.config
+
+        from ml.training.ppo_trainer import PPOTrainer, PPOConfig
+        from ml.training.decision_exporter import DecisionExporter, ExporterConfig
+
+        # Set up decision exporter for this generation
+        exporter = DecisionExporter(ExporterConfig(
+            output_dir=cfg.results_dir,
+            only_wins=True,
+            model_version=gen_tag,
+        ))
+
+        ppo_config = PPOConfig(
+            iterations=cfg.ppo_iterations,
+            episodes_per_iter=cfg.ppo_episodes_per_iter,
+            ppo_epochs=4,
+            batch_size=cfg.ppo_batch_size,
+            clip_epsilon=cfg.ppo_clip_epsilon,
+            entropy_coeff=entropy_coeff or cfg.ppo_entropy_coeff,
+            learning_rate=learning_rate or cfg.ppo_lr,
+            lr_schedule="cosine",
+            min_lr=1e-5,
+            opponent=cfg.opponent,
+            playstyle=cfg.playstyle,
+            checkpoint_dir=gen_checkpoint_dir,
+            save_every=max(1, cfg.ppo_iterations // 5),
+            eval_every=max(1, cfg.ppo_iterations // 10),
+            eval_episodes=cfg.ppo_eval_episodes,
+            load_supervised=supervised_checkpoint,
+        )
+
+        ppo_trainer = PPOTrainer(ppo_config)
+
+        # Monkey-patch collect_rollouts to include exporter
+        # The exporter is already wired into self_play.collect_rollouts
+        # via the exporter parameter, so we wrap the train loop.
+        original_collect = None
+
+        from ml.training import self_play as sp_module
+
+        _original_collect_rollouts = sp_module.collect_rollouts
+
+        def _instrumented_collect_rollouts(
+            agent_model, opponent_policy, buffer,
+            num_episodes=64, playstyle="midrange",
+            reward_config=None, **kwargs
+        ):
+            return _original_collect_rollouts(
+                agent_model=agent_model,
+                opponent_policy=opponent_policy,
+                buffer=buffer,
+                num_episodes=num_episodes,
+                playstyle=playstyle,
+                reward_config=reward_config,
+                exporter=exporter,
+            )
+
+        # Temporarily replace module-level function
+        sp_module.collect_rollouts = _instrumented_collect_rollouts
+        try:
+            summary = ppo_trainer.train()
+        finally:
+            # Restore original
+            sp_module.collect_rollouts = _original_collect_rollouts
+
+        return summary, exporter
+
+    # ------------------------------------------------------------------
+    # Step 4: Quality Gate
+    # ------------------------------------------------------------------
+
+    def _quality_gate_check(
+        self,
+        ppo_win_rate: float,
+        total_episodes: int,
+        exporter: DecisionExporter,
+    ) -> GateVerdict:
+        """Run quality gate checks on the PPO output."""
+        # Win rate gate
+        win_verdict = self.quality_gate.check_win_rate(
+            ppo_win_rate=ppo_win_rate,
+            total_episodes=total_episodes,
+        )
+        if not win_verdict.accepted:
+            return win_verdict
+
+        # If we have baseline accuracy and this isn't the first generation,
+        # we could run a post-merge accuracy check here. For now, the win
+        # rate gate is the primary gatekeeper during the loop. The accuracy
+        # gate will be checked on the next generation's supervised training
+        # by comparing against self._baseline_accuracy.
+        return GateVerdict(
+            accepted=True,
+            reason=(
+                f"Win rate gate passed ({ppo_win_rate:.1%} >= "
+                f"{self.config.min_ppo_win_rate:.1%}). "
+                f"PPO data accepted for merge."
+            ),
+            metrics={
+                "ppo_win_rate": ppo_win_rate,
+                "total_episodes": total_episodes,
+                "exported_decisions": exporter.stats["exported_decisions"],
+            },
+        )
+
+    # ------------------------------------------------------------------
+    # Convergence detection
+    # ------------------------------------------------------------------
+
+    def _check_convergence(self) -> bool:
+        """
+        Check if win rate has plateaued over recent generations.
+
+        Returns True if the loop should stop.
+        """
+        cfg = self.config
+        passed = [g for g in self.generations if g.status == "passed"]
+
+        if len(passed) < cfg.convergence_window:
+            return False
+
+        recent = passed[-cfg.convergence_window:]
+        win_rates = [g.ppo_best_win_rate for g in recent]
+
+        # Check if max improvement across the window is below threshold
+        improvement = max(win_rates) - min(win_rates)
+
+        logger.info(
+            "  Convergence check: last %d win rates = %s, "
+            "spread = %.4f (threshold = %.4f)",
+            cfg.convergence_window,
+            [f"{wr:.3f}" for wr in win_rates],
+            improvement,
+            cfg.convergence_threshold,
+        )
+
+        return improvement < cfg.convergence_threshold
+
+    # ------------------------------------------------------------------
+    # Device detection
+    # ------------------------------------------------------------------
+
+    def _detect_device(self) -> str:
+        """Auto-detect best compute device."""
+        try:
+            import torch
+            if torch.cuda.is_available():
+                return "cuda"
+            if hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
+                return "mps"
+        except ImportError:
+            pass
+        return "cpu"
+
+    # ------------------------------------------------------------------
+    # History & summary persistence
+    # ------------------------------------------------------------------
+
+    def _save_history(self):
+        """Save generation history to JSON."""
+        path = os.path.join(self.config.history_dir, "generations.json")
+        history = [g.to_dict() for g in self.generations]
+        with open(path, "w") as f:
+            json.dump(history, f, indent=2)
+        logger.info("  Generation history saved: %s", path)
+
+    def _build_summary(self, total_time: float) -> Dict:
+        """Build final summary dict."""
+        passed = [g for g in self.generations if g.status == "passed"]
+        failed = [g for g in self.generations if g.status == "failed"]
+
+        best_wr = max(
+            (g.ppo_best_win_rate for g in self.generations), default=0.0
+        )
+
+        return {
+            "generations_run": len(self.generations),
+            "generations_passed": len(passed),
+            "generations_failed": len(failed),
+            "best_win_rate": best_wr,
+            "converged": self._check_convergence() if len(passed) >= self.config.convergence_window else False,
+            "total_time_s": round(total_time, 1),
+            "device": self._device,
+            "config": {
+                "max_iterations": self.config.max_iterations,
+                "convergence_window": self.config.convergence_window,
+                "convergence_threshold": self.config.convergence_threshold,
+                "ppo_iterations": self.config.ppo_iterations,
+                "supervised_epochs": self.config.supervised_epochs,
+            },
+            "generations": [g.to_dict() for g in self.generations],
+        }
+
+    def _save_summary(self, summary: Dict):
+        """Save final summary to JSON."""
+        path = os.path.join(self.config.history_dir, "summary.json")
+        with open(path, "w") as f:
+            json.dump(summary, f, indent=2, default=str)
+        logger.info("  Summary saved: %s", path)
+
+
+# ═══════════════════════════════════════════════════════════
+# CLI Entry Point
+# ═══════════════════════════════════════════════════════════
+
+def main():
+    """CLI entry point for the distillation loop."""
+    import argparse
+
+    parser = argparse.ArgumentParser(
+        description="Commander AI Lab — Closed-Loop Distillation"
+    )
+
+    # Loop control
+    parser.add_argument(
+        "--max-iterations", type=int, default=10,
+        help="Maximum number of distillation generations (default: 10)",
+    )
+    parser.add_argument(
+        "--convergence-window", type=int, default=3,
+        help="Number of generations to check for win-rate plateau (default: 3)",
+    )
+    parser.add_argument(
+        "--convergence-threshold", type=float, default=0.01,
+        help="Min win-rate spread to not be considered converged (default: 0.01)",
+    )
+
+    # Paths
+    parser.add_argument(
+        "--results-dir", default="data/results",
+        help="Directory containing JSONL decision files (default: data/results)",
+    )
+    parser.add_argument(
+        "--models-dir", default="ml/models",
+        help="Directory for dataset NPZ files (default: ml/models)",
+    )
+    parser.add_argument(
+        "--checkpoint-dir", default="ml/models/checkpoints",
+        help="Directory for model checkpoints (default: ml/models/checkpoints)",
+    )
+
+    # Supervised training
+    parser.add_argument("--sup-epochs", type=int, default=30)
+    parser.add_argument("--sup-lr", type=float, default=1e-3)
+    parser.add_argument("--sup-batch-size", type=int, default=64)
+    parser.add_argument("--sup-patience", type=int, default=5)
+
+    # PPO self-play
+    parser.add_argument("--ppo-iterations", type=int, default=50)
+    parser.add_argument("--ppo-episodes", type=int, default=64)
+    parser.add_argument("--ppo-lr", type=float, default=3e-4)
+    parser.add_argument("--ppo-batch-size", type=int, default=256)
+    parser.add_argument("--ppo-eval-episodes", type=int, default=100)
+    parser.add_argument(
+        "--opponent", default="heuristic",
+        choices=["heuristic", "random", "self"],
+    )
+    parser.add_argument("--playstyle", default="midrange")
+
+    # Dataset
+    parser.add_argument("--forge-weight", type=float, default=1.0)
+    parser.add_argument("--ppo-weight", type=float, default=0.5)
+    parser.add_argument("--min-reward", type=float, default=0.0)
+
+    # Quality gate
+    parser.add_argument("--min-win-rate", type=float, default=0.30)
+    parser.add_argument("--min-forge-accuracy", type=float, default=0.35)
+    parser.add_argument("--max-accuracy-drop", type=float, default=0.03)
+
+    args = parser.parse_args()
+
+    logging.basicConfig(
+        level=logging.INFO,
+        format="%(message)s",
+    )
+
+    config = DistillationConfig(
+        max_iterations=args.max_iterations,
+        convergence_window=args.convergence_window,
+        convergence_threshold=args.convergence_threshold,
+        results_dir=args.results_dir,
+        models_dir=args.models_dir,
+        checkpoint_dir=args.checkpoint_dir,
+        supervised_epochs=args.sup_epochs,
+        supervised_lr=args.sup_lr,
+        supervised_batch_size=args.sup_batch_size,
+        supervised_patience=args.sup_patience,
+        ppo_iterations=args.ppo_iterations,
+        ppo_episodes_per_iter=args.ppo_episodes,
+        ppo_batch_size=args.ppo_batch_size,
+        ppo_lr=args.ppo_lr,
+        ppo_eval_episodes=args.ppo_eval_episodes,
+        opponent=args.opponent,
+        playstyle=args.playstyle,
+        forge_weight=args.forge_weight,
+        ppo_weight=args.ppo_weight,
+        min_reward_threshold=args.min_reward,
+        min_ppo_win_rate=args.min_win_rate,
+        min_forge_accuracy=args.min_forge_accuracy,
+        max_accuracy_drop=args.max_accuracy_drop,
+    )
+
+    loop = DistillationLoop(config)
+    summary = loop.run()
+    print(json.dumps(summary, indent=2, default=str))
+
+
+if __name__ == "__main__":
+    main()