diff --git a/app/harness/pools.py b/app/harness/pools.py
index c46747e..89763de 100644
--- a/app/harness/pools.py
+++ b/app/harness/pools.py
@@ -844,6 +844,28 @@ def build_or_load_pools(
                         len(new_types),
                         sorted(new_types),
                     )
+        else:
+            # global：校验 baseline_run_id 与（若有）manifest 内容指纹，
+            # 拒绝静默加载与 seed 错配 / 被篡改的冻结切分（P5 fail loud）。
+            frozen_baseline = raw.get("baseline_run_id")
+            if frozen_baseline != baseline_run_id:
+                raise ValueError(
+                    f"冻结 pools.json 的 baseline_run_id={frozen_baseline!r} 与 seed "
+                    f"的 {baseline_run_id!r} 不一致，拒绝静默加载错配切分。"
+                )
+            manifest_path = config.workspace_dir / "split_manifest.json"
+            if manifest_path.exists():
+                import hashlib
+
+                manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
+                actual_sha = hashlib.sha256(
+                    pools_path.read_text(encoding="utf-8").encode("utf-8")
+                ).hexdigest()
+                if manifest.get("pools_sha256") != actual_sha:
+                    raise ValueError(
+                        "pools.json 内容指纹与 split_manifest.pools_sha256 不符，"
+                        "冻结产物疑被篡改，拒绝加载。"
+                    )
 
         return load_pools(pools_path)
 
diff --git a/tests/unit/test_harness_pools.py b/tests/unit/test_harness_pools.py
index 9dd0eb7..2cc1b75 100644
--- a/tests/unit/test_harness_pools.py
+++ b/tests/unit/test_harness_pools.py
@@ -18,6 +18,7 @@ import pytest
 from app.harness.pools import (
     GlobalPoolStrategy,
     PerCategoryPoolStrategy,
+    build_or_load_pools,
     build_pools,
     load_pools,
     save_pools,
@@ -291,6 +292,76 @@ class TestBuildOrLoadPoolsFrozen:
             load_ids = [q.question_id for q in getattr(loaded, pool_name)]
             assert orig_ids == load_ids, f"{pool_name} 冻结后 ID 顺序不一致"
 
+    def _run_config_for_frozen(self, tmp_path: Path, seed_name: str) -> object:
+        """构造指向 tmp workspace/store + 指定种子名的最小 train RunConfig。"""
+        from app.harness.config import RunConfig
+
+        return RunConfig(
+            workspace_dir=tmp_path / "ws",
+            store_dir=tmp_path / "store",
+            mode="train",
+            concurrency=4,
+            max_steps=10,
+            skill_mode="auto",
+            n_samples=0,
+            questions="benchmarks/Video-MME",
+            skills_version="v1",
+            prompts_version="v1",
+            epochs=1,
+            diag_size=10,
+            diag_correct_ratio=0.5,
+            val_size=10,
+            val_correct_ratio=0.5,
+            edit_budget_start=5,
+            edit_budget_end=2,
+            batch_size=15,
+            min_class_per_batch=2,
+            eval_min_per_class=2,
+            early_stop_patience=4,
+            test_size=10,
+            use_slow_momentum=True,
+            gate_e_confirm=20.0,
+            gate_e_provisional=3.0,
+            gate_w_net_min=2,
+            gate_delta_min=0.02,
+            gate_lambda_dir=-0.642,
+            gate_e_rollback=10.0,
+            gate_block=8,
+            gate_n_max=40,
+            gate_p_low=0.05,
+            gate_p_high=0.95,
+            gate_probe_quota=0.2,
+            gate_gamma_decay=0.9,
+            gate_cooldown_steps=2,
+            gate_guard_err=0.10,
+            skill_update_mode="patch",
+            appendix_consolidate_threshold=6,
+            fresh=True,
+            seed=seed_name,
+            test_questions="",  # 绕过 _to_pool_config 的 resolve_paths(manifest 依赖)
+        )
+
+    def test_global_frozen_rejects_baseline_mismatch(self, tmp_path: Path) -> None:
+        """global 冻结 pools 的 baseline_run_id 与 seed 不符时 fail-loud。"""
+        seed_name = "myseed"
+        seed_dir = tmp_path / "store" / "seeds" / seed_name
+        seed_dir.mkdir(parents=True)
+        (seed_dir / "seed.json").write_text(
+            json.dumps({"baseline_run_id": "infer_adhoc", "parent": None})
+        )
+
+        ws = tmp_path / "ws"
+        ws.mkdir()
+        (ws / "pools.json").write_text(
+            json.dumps({"split_mode": "global", "baseline_run_id": "other"}),
+            encoding="utf-8",
+        )
+
+        config = self._run_config_for_frozen(tmp_path, seed_name)
+        strategy = GlobalPoolStrategy()
+        with pytest.raises(ValueError, match="baseline_run_id"):
+            build_or_load_pools(config, strategy, tmp_path / "nonexistent.db")
+
 
 class TestGlobalPoolStrategy:
     """GlobalPoolStrategy 封装现有全局三分逻辑。"""