diff --git a/server/src/main/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStub.java b/server/src/main/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStub.java
index e7089e13..5f89438e 100644
--- a/server/src/main/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStub.java
+++ b/server/src/main/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStub.java
@@ -17,25 +17,18 @@
 
 package org.apache.rocketmq.studio.instance.group;
 
+import org.apache.rocketmq.studio.common.exception.BusinessException;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Component;
 
-import java.time.LocalDateTime;
-import java.util.List;
-
 @Slf4j
 @Component
 public class ConsumerDiagnosticsProviderStub implements ConsumerDiagnosticsProvider {
 
     @Override
     public ConsumerStackTraceVO getConsumerStack(String groupName, String clientId) {
-        log.warn("ConsumerDiagnosticsProviderStub.getConsumerStack called - returning empty stack");
-        return ConsumerStackTraceVO.builder()
-                .groupName(groupName)
-                .clientId(clientId)
-                .capturedAt(LocalDateTime.now())
-                .threadCount(0)
-                .threads(List.of())
-                .build();
+        log.warn("ConsumerDiagnosticsProviderStub.getConsumerStack called without a real diagnostics provider. "
+                + "groupName={}, clientId={}", groupName, clientId);
+        throw new BusinessException(501, "Consumer diagnostics provider is not configured");
     }
 }
diff --git a/server/src/test/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStubTest.java b/server/src/test/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStubTest.java
new file mode 100644
index 00000000..4f486440
--- /dev/null
+++ b/server/src/test/java/org/apache/rocketmq/studio/instance/group/ConsumerDiagnosticsProviderStubTest.java
@@ -0,0 +1,36 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.rocketmq.studio.instance.group;
+
+import org.apache.rocketmq.studio.common.exception.BusinessException;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class ConsumerDiagnosticsProviderStubTest {
+
+    private final ConsumerDiagnosticsProviderStub provider = new ConsumerDiagnosticsProviderStub();
+
+    @Test
+    void getConsumerStackShouldFailWhenRealProviderIsMissing() {
+        assertThatThrownBy(() -> provider.getConsumerStack("cg-orders", "client-1"))
+                .isInstanceOf(BusinessException.class)
+                .hasMessage("Consumer diagnostics provider is not configured")
+                .satisfies(ex -> assertThat(((BusinessException) ex).getCode()).isEqualTo(501));
+    }
+}