diff --git a/backend-java/src/test/java/com/nanri/aiimage/metrics/TaskTerminalMetricsTest.java b/backend-java/src/test/java/com/nanri/aiimage/metrics/TaskTerminalMetricsTest.java
new file mode 100644
index 00000000..7ab7c5b2
--- /dev/null
+++ b/backend-java/src/test/java/com/nanri/aiimage/metrics/TaskTerminalMetricsTest.java
@@ -0,0 +1,86 @@
+package com.nanri.aiimage.metrics;
+
+import io.micrometer.core.instrument.Counter;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * task-182：task.success/failed/cancelled 终态计数契约（spec 11 §1）。
+ * 每个终态独立计数、分 moduleType；单次终态调用精确 +1，互不串扰。
+ */
+class TaskTerminalMetricsTest {
+
+    private final SimpleMeterRegistry registry = new SimpleMeterRegistry();
+    private final TaskObservabilityMetrics metrics = new TaskObservabilityMetrics("server-110", registry);
+
+    private Counter counter(String terminal, String moduleType) {
+        return registry.get("aiimage.task." + terminal).tag("moduleType", moduleType).counter();
+    }
+
+    @Test
+    void successCounted() {
+        metrics.taskTerminal("similarasin", "success");
+        assertEquals(1.0, counter("success", "similarasin").count());
+    }
+
+    @Test
+    void failedCounted() {
+        metrics.taskTerminal("similarasin", "failed");
+        assertEquals(1.0, counter("failed", "similarasin").count());
+    }
+
+    @Test
+    void cancelledCounted() {
+        metrics.taskTerminal("similarasin", "cancelled");
+        assertEquals(1.0, counter("cancelled", "similarasin").count());
+    }
+
+    @Test
+    void moduleSplitIndependent() {
+        metrics.taskTerminal("similarasin", "success");
+        metrics.taskTerminal("publish", "success");
+        assertEquals(1.0, counter("success", "similarasin").count());
+        assertEquals(1.0, counter("success", "publish").count());
+    }
+
+    @Test
+    void singleTerminalCallCountsOnce() {
+        metrics.taskTerminal("brand", "failed");
+        assertEquals(1.0, counter("failed", "brand").count(), "单次终态调用精确 +1");
+    }
+
+    @Test
+    void terminalTypesDoNotCrossCount() {
+        metrics.taskTerminal("similarasin", "success");
+        metrics.taskTerminal("similarasin", "failed");
+        assertEquals(1.0, counter("success", "similarasin").count());
+        assertEquals(1.0, counter("failed", "similarasin").count());
+        assertEquals(0.0, registry.find("aiimage.task.cancelled").tag("moduleType", "similarasin").counter() == null
+                ? 0.0
+                : registry.find("aiimage.task.cancelled").tag("moduleType", "similarasin").counter().count(),
+                "success/failed 不应污染 cancelled");
+    }
+
+    @Test
+    void terminalNamesFrozen() {
+        metrics.taskTerminal("similarasin", "success");
+        metrics.taskTerminal("similarasin", "failed");
+        metrics.taskTerminal("similarasin", "cancelled");
+        assertTrue(registry.getMeters().stream()
+                .anyMatch(m -> m.getId().getName().equals("aiimage.task.success")));
+        assertTrue(registry.getMeters().stream()
+                .anyMatch(m -> m.getId().getName().equals("aiimage.task.failed")));
+        assertTrue(registry.getMeters().stream()
+                .anyMatch(m -> m.getId().getName().equals("aiimage.task.cancelled")));
+    }
+
+    @Test
+    void countersCarryInstanceLabel() {
+        metrics.taskTerminal("similarasin", "success");
+        assertEquals("server-110",
+                registry.get("aiimage.task.success").counter().getId().getTag("instanceId"));
+    }
+}