diff --git a/rock/admin/metrics/constants.py b/rock/admin/metrics/constants.py
index 48c69b8c04..66c2d8c580 100644
--- a/rock/admin/metrics/constants.py
+++ b/rock/admin/metrics/constants.py
@@ -4,6 +4,7 @@ class MetricsConstants:
     SANDBOX_REQUEST_TOTAL = "request.total"
     SANDBOX_REQUEST_SUCCESS = "request.success"
     SANDBOX_REQUEST_FAILURE = "request.failure"
+    SANDBOX_REQUEST_CLIENT_ERROR = "request.client_error"
 
     SANDBOX_REQUEST_RT = "request.rt"
 
diff --git a/rock/admin/metrics/decorator.py b/rock/admin/metrics/decorator.py
index 39bdceb932..c647dc9f88 100644
--- a/rock/admin/metrics/decorator.py
+++ b/rock/admin/metrics/decorator.py
@@ -9,6 +9,7 @@
 
 from rock.admin.metrics.constants import MetricsConstants
 from rock.admin.metrics.monitor import MetricsMonitor
+from rock.sdk.common.exceptions import BadRequestRockError
 
 if TYPE_CHECKING:
     from rock.sandbox.sandbox_meta_store import SandboxMetaStore
@@ -130,7 +131,10 @@ def _record_metrics(metrics_monitor: MetricsMonitor, result, attributes: dict, s
     is_exception = isinstance(result, Exception)
     if is_exception:
         metric_attrs = {**attributes, "error_type": type(result).__name__}
-        metrics_monitor.record_counter_by_name(f"{metric_prefix}.failure", 1, metric_attrs)
+        if isinstance(result, BadRequestRockError):
+            metrics_monitor.record_counter_by_name(f"{metric_prefix}.client_error", 1, metric_attrs)
+        else:
+            metrics_monitor.record_counter_by_name(f"{metric_prefix}.failure", 1, metric_attrs)
     else:
         metric_attrs = attributes
         metrics_monitor.record_counter_by_name(f"{metric_prefix}.success", 1, metric_attrs)
diff --git a/rock/admin/metrics/monitor.py b/rock/admin/metrics/monitor.py
index 44c8d077bb..86a9ed7755 100644
--- a/rock/admin/metrics/monitor.py
+++ b/rock/admin/metrics/monitor.py
@@ -72,6 +72,7 @@ def _register_metrics(self):
         # Request count metrics
         self._register_counter(MetricsConstants.SANDBOX_REQUEST_SUCCESS, "Number of successful requests")
         self._register_counter(MetricsConstants.SANDBOX_REQUEST_FAILURE, "Number of failed requests")
+        self._register_counter(MetricsConstants.SANDBOX_REQUEST_CLIENT_ERROR, "Number of client error requests")
         self._register_counter(MetricsConstants.SANDBOX_REQUEST_TOTAL, "Number of total requests")
         # Sandbox metrics
         self._register_gauge(MetricsConstants.SANDBOX_TOTAL_COUNT, "Number of sandbox")
diff --git a/tests/unit/admin/metrics/test_decorator.py b/tests/unit/admin/metrics/test_decorator.py
index 08ff686353..dd078bb2bb 100644
--- a/tests/unit/admin/metrics/test_decorator.py
+++ b/tests/unit/admin/metrics/test_decorator.py
@@ -189,9 +189,9 @@ async def do_something(self, sandbox_id):
     assert attrs["namespace"] == "n1"
 
 
-def test_record_metrics_bad_request_goes_to_failure():
-    """BadRequestRockError lands in the generic `.failure` bucket along with
-    every other exception type — there is no separate client-fault bucket."""
+def test_record_metrics_bad_request_goes_to_client_error():
+    """BadRequestRockError lands in the `.client_error` bucket, not `.failure`,
+    so client faults don't pollute server failure metrics."""
     mock_metrics_monitor = Mock(spec=MetricsMonitor)
     attributes = {"operation": "test_op"}
     start_time = 0
@@ -202,6 +202,32 @@ def test_record_metrics_bad_request_goes_to_failure():
             _record_metrics(mock_metrics_monitor, exception, attributes, start_time, "test")
 
     error_attrs = {**attributes, "error_type": "BadRequestRockError"}
-    mock_metrics_monitor.record_counter_by_name.assert_any_call("test.failure", 1, error_attrs)
+    mock_metrics_monitor.record_counter_by_name.assert_any_call("test.client_error", 1, error_attrs)
     mock_metrics_monitor.record_gauge_by_name.assert_called_once_with("test.rt", 1000.0, error_attrs)
     mock_metrics_monitor.record_counter_by_name.assert_any_call("test.total", 1, error_attrs)
+    # Verify it does NOT go to .failure
+    failure_calls = [c for c in mock_metrics_monitor.record_counter_by_name.call_args_list if c[0][0] == "test.failure"]
+    assert len(failure_calls) == 0
+
+
+def test_record_metrics_server_error_goes_to_failure():
+    """Non-client exceptions (e.g. InternalServerRockError, generic Exception)
+    still land in the `.failure` bucket."""
+    from rock.sdk.common.exceptions import InternalServerRockError
+
+    mock_metrics_monitor = Mock(spec=MetricsMonitor)
+    attributes = {"operation": "test_op"}
+    start_time = 0
+    exception = InternalServerRockError("internal error")
+
+    with patch("rock.admin.metrics.decorator.time.perf_counter", return_value=1.0):
+        with pytest.raises(InternalServerRockError):
+            _record_metrics(mock_metrics_monitor, exception, attributes, start_time, "test")
+
+    error_attrs = {**attributes, "error_type": "InternalServerRockError"}
+    mock_metrics_monitor.record_counter_by_name.assert_any_call("test.failure", 1, error_attrs)
+    # Verify it does NOT go to .client_error
+    client_error_calls = [
+        c for c in mock_metrics_monitor.record_counter_by_name.call_args_list if c[0][0] == "test.client_error"
+    ]
+    assert len(client_error_calls) == 0