diff --git a/.env.example b/.env.example
index a0c1ce0..a0d4906 100644
--- a/.env.example
+++ b/.env.example
@@ -41,7 +41,7 @@ REDIS_URL=redis://localhost:6379/0
 LLM_TIMEOUT=120
 LLM_MAX_RETRIES=3
 LLM_RETRY_BASE_DELAY=2.0
-LLM_CIRCUIT_BREAKER_THRESHOLD=5  # 实际阈值 = max(此值, concurrency*2)
+LLM_CIRCUIT_BREAKER_THRESHOLD=48  # 实际阈值 = max(此值, concurrency*2)
 LLM_CIRCUIT_BREAKER_COOLDOWN=60
 LLM_TTFT_TIMEOUT=30
 LLM_INTER_TOKEN_TIMEOUT=15
diff --git a/config/default.yaml b/config/default.yaml
index 8861fff..298d07e 100644
--- a/config/default.yaml
+++ b/config/default.yaml
@@ -27,8 +27,8 @@ harness:
   workspace_dir: "workspaces/default"
   store_dir: store
   mode: infer
-  concurrency: 12
-  max_steps: 15
+  concurrency: 24
+  max_steps: 40
   skill_mode: auto
   n_samples: 0
   questions: "benchmarks/Video-MME"
diff --git a/tests/unit/test_harness_config.py b/tests/unit/test_harness_config.py
index 555cb79..1f2ec39 100644
--- a/tests/unit/test_harness_config.py
+++ b/tests/unit/test_harness_config.py
@@ -23,8 +23,8 @@ def _valid_kwargs() -> dict:
         "store_dir": Path("store"),
         "mode": "infer",
         "run_id": "",
-        "concurrency": 12,
-        "max_steps": 15,
+        "concurrency": 24,
+        "max_steps": 40,
         "skill_mode": "auto",
         "n_samples": 0,
         "questions": "benchmarks/Video-MME",
@@ -453,7 +453,7 @@ class TestLoadConfigCliOverrides:
         yaml_path = _write_yaml(tmp_path, harness_data)
 
         cfg = load_config(yaml_path, cli_overrides={"concurrency": None, "max_steps": 20})
-        assert cfg.concurrency == 12  # YAML 默认值
+        assert cfg.concurrency == 24  # YAML 默认值
         assert cfg.max_steps == 20
 
     def test_cli_run_id_override(self, tmp_path: Path) -> None:
@@ -483,7 +483,7 @@ class TestLoadConfigCliOverrides:
         yaml_path = _write_yaml(tmp_path, harness_data)
 
         cfg = load_config(yaml_path, cli_overrides={"nonexistent_field": 42})
-        assert cfg.concurrency == 12  # 正常字段不受影响
+        assert cfg.concurrency == 24  # 正常字段不受影响
 
     def test_validation_runs_after_loading(self, tmp_path: Path) -> None:
         """load_config 加载后应运行校验，非法值应报错。"""
@@ -545,7 +545,7 @@ class TestLoadConfigRealYaml:
         assert cfg.mode == "infer"
         assert cfg.gate_e_confirm == 20.0
         assert cfg.batch_size == 15
-        assert cfg.concurrency == 12
+        assert cfg.concurrency == 24
         assert cfg.workspace_dir == Path("workspaces/default")
         assert cfg.store_dir == Path("store")
         assert cfg.skill_mode == "auto"