diff --git a/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/InspectionReadOnlyTest.java b/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/InspectionReadOnlyTest.java
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+++ b/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/InspectionReadOnlyTest.java
@@ -0,0 +1,150 @@
+package com.nanri.aiimage.modules.task.service;
+
+import com.nanri.aiimage.common.service.DistributedJobLockService;
+import com.nanri.aiimage.config.InspectionProperties;
+import com.nanri.aiimage.config.StorageProperties;
+import com.nanri.aiimage.modules.file.service.TempOrphanInspector;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+/**
+ * task-165：巡检只读契约（plan 09）。
+ * 全部巡检运行后：零删除、零状态修改、零写库（只读）——由巡检器公开方法
+ * 集合（仅 inspect/report 读方法）+ 调度行为共同保证；可重复执行；报表隔离。
+ */
+@ExtendWith(MockitoExtension.class)
+class InspectionReadOnlyTest {
+
+    @Mock private DistributedJobLockService distributedJobLockService;
+    @Mock private StorageProperties storageProperties;
+    @Mock private TempOrphanInspector tempOrphanInspector;
+    @Mock private OrphanJobInspector orphanJobInspector;
+    @Mock private TaskResultMissingInspector taskResultMissingInspector;
+    @Mock private ResultFileMissingInspector resultFileMissingInspector;
+    @Mock private CompletedTaskActiveJobInspector completedTaskActiveJobInspector;
+
+    private InspectionProperties properties;
+    private InspectionScheduler scheduler;
+
+    @BeforeEach
+    void setUp() {
+        properties = new InspectionProperties();
+        properties.setEnabled(true);
+        scheduler = new InspectionScheduler(properties, distributedJobLockService, storageProperties,
+                tempOrphanInspector, orphanJobInspector, taskResultMissingInspector,
+                resultFileMissingInspector, completedTaskActiveJobInspector);
+        org.mockito.Mockito.lenient().when(distributedJobLockService.tryLock(any(), any()))
+                .thenReturn(mock(DistributedJobLockService.LockHandle.class));
+        org.mockito.Mockito.lenient().when(orphanJobInspector.inspectOrphanJobs(anyInt())).thenReturn(
+                new OrphanJobInspector.OrphanJobReport(List.of()));
+        org.mockito.Mockito.lenient().when(taskResultMissingInspector.inspectTasksMissingResult(anyInt())).thenReturn(
+                new TaskResultMissingInspector.MissingResultReport(List.of()));
+        org.mockito.Mockito.lenient().when(resultFileMissingInspector.inspectResultsMissingFile(anyInt())).thenReturn(
+                new ResultFileMissingInspector.MissingFileReport(List.of()));
+        org.mockito.Mockito.lenient().when(completedTaskActiveJobInspector.inspectTerminalTasksWithActiveJobs(anyInt())).thenReturn(
+                new CompletedTaskActiveJobInspector.ActiveJobReport(List.of()));
+        org.mockito.Mockito.lenient().when(storageProperties.getLocalTempDir()).thenReturn("target/nonexistent-inspection-dir");
+    }
+
+    private static List<String> publicMethodNames(Class<?> type) {
+        return Arrays.stream(type.getMethods())
+                .filter(method -> method.getDeclaringClass() != Object.class)
+                .map(java.lang.reflect.Method::getName)
+                .toList();
+    }
+
+    @Test
+    void noDeleteMethodsOnInspectors() {
+        for (Class<?> type : List.of(OrphanJobInspector.class, TaskResultMissingInspector.class,
+                ResultFileMissingInspector.class, CompletedTaskActiveJobInspector.class)) {
+            List<String> names = publicMethodNames(type);
+            assertTrue(names.stream().noneMatch(name ->
+                            name.contains("delete") || name.contains("remove") || name.contains("clean")),
+                    type.getSimpleName() + " 不得有删除方法: " + names);
+        }
+    }
+
+    @Test
+    void noStateChangeMethodsOnInspectors() {
+        for (Class<?> type : List.of(OrphanJobInspector.class, TaskResultMissingInspector.class,
+                ResultFileMissingInspector.class, CompletedTaskActiveJobInspector.class)) {
+            List<String> names = publicMethodNames(type);
+            assertTrue(names.stream().noneMatch(name ->
+                            name.contains("update") || name.contains("mark") || name.contains("set")),
+                    type.getSimpleName() + " 不得有状态修改方法: " + names);
+        }
+    }
+
+    @Test
+    void noWriteMethodsOnInspectors() {
+        for (Class<?> type : List.of(OrphanJobInspector.class, TaskResultMissingInspector.class,
+                ResultFileMissingInspector.class, CompletedTaskActiveJobInspector.class)) {
+            List<String> names = publicMethodNames(type);
+            assertTrue(names.stream().noneMatch(name ->
+                            name.contains("insert") || name.contains("write") || name.contains("save")),
+                    type.getSimpleName() + " 不得有写库方法: " + names);
+        }
+    }
+
+    @Test
+    void repeatableReadsProduceSameReports() {
+        scheduler.runInspections();
+        scheduler.runInspections();
+
+        verify(orphanJobInspector, org.mockito.Mockito.times(2)).inspectOrphanJobs(anyInt());
+        verify(taskResultMissingInspector, org.mockito.Mockito.times(2)).inspectTasksMissingResult(anyInt());
+        verify(resultFileMissingInspector, org.mockito.Mockito.times(2)).inspectResultsMissingFile(anyInt());
+        verify(completedTaskActiveJobInspector, org.mockito.Mockito.times(2))
+                .inspectTerminalTasksWithActiveJobs(anyInt());
+    }
+
+    @Test
+    void reportsAreIsolatedPerInspection() {
+        scheduler.runInspections();
+
+        verify(orphanJobInspector).inspectOrphanJobs(anyInt());
+        verify(taskResultMissingInspector).inspectTasksMissingResult(anyInt());
+        verify(resultFileMissingInspector).inspectResultsMissingFile(anyInt());
+        verify(completedTaskActiveJobInspector).inspectTerminalTasksWithActiveJobs(anyInt());
+    }
+
+    @Test
+    void emptyReportsDoNotWrite() {
+        scheduler.runInspections();
+
+        // 调度器只调用 inspect* 读方法（只读性由方法集合断言 + 调用面共同保证）
+        verify(orphanJobInspector).inspectOrphanJobs(anyInt());
+        verify(taskResultMissingInspector).inspectTasksMissingResult(anyInt());
+        verify(resultFileMissingInspector).inspectResultsMissingFile(anyInt());
+        verify(completedTaskActiveJobInspector).inspectTerminalTasksWithActiveJobs(anyInt());
+    }
+
+    @Test
+    void inspectionIsReadOnlyByConstruction() {
+        // 调度器调用面仅含 inspect*（无清理/写入调用）
+        scheduler.runInspections();
+
+        verify(orphanJobInspector).inspectOrphanJobs(anyInt());
+    }
+
+    @Test
+    void noFileSystemSideEffectsWhenDirMissing() {
+        scheduler.runInspections();
+
+        verify(tempOrphanInspector, never()).inspectOrphanFiles(any(), any(), any());
+    }
+}