diff --git a/frontend/src/views/__tests__/CloudFolderRenderedFlow.test.js b/frontend/src/views/__tests__/CloudFolderRenderedFlow.test.js
index d81981e..70851c3 100644
--- a/frontend/src/views/__tests__/CloudFolderRenderedFlow.test.js
+++ b/frontend/src/views/__tests__/CloudFolderRenderedFlow.test.js
@@ -39,19 +39,42 @@ const mockSetBrowseState = vi.fn()
 const mockSelectConnection = vi.fn()
 const mockFetchConnections = vi.fn().mockResolvedValue(undefined)
 
+/**
+ * Reactive mock store state — must use Vue refs so that CloudFolderView's
+ * template reactivity (`:folder-freshness="cloudStore.folderFreshness"`) picks
+ * up changes when setBrowseState is called during the browse cycle (D-12/D-13).
+ */
+import { ref } from 'vue'
+
+const _mockFolderFreshness = ref(null)
+const _mockLastRefreshedAt = ref(null)
+const _mockCapabilities = ref(null)
+const _mockByteAvailability = ref(null)
+
 vi.mock('../../stores/cloudConnections.js', () => ({
   useCloudConnectionsStore: () => ({
     connections: [
       { id: 'conn-rendered-1', provider: 'webdav', display_name: 'Test WebDAV' },
     ],
     loading: false,
-    capabilities: null,
-    folderFreshness: null,
-    lastRefreshedAt: null,
-    byteAvailability: null,
+    get capabilities() { return _mockCapabilities.value },
+    get folderFreshness() { return _mockFolderFreshness.value },
+    get lastRefreshedAt() { return _mockLastRefreshedAt.value },
+    get byteAvailability() { return _mockByteAvailability.value },
     fetchConnections: mockFetchConnections,
     selectConnection: mockSelectConnection,
-    setBrowseState: mockSetBrowseState,
+    /**
+     * D-12: setBrowseState must update reactive folderFreshness so CloudFolderView
+     * propagates it to StorageBrowser as a prop. Without reactivity, the health
+     * banner never appears (T-13-30 mitigated here in GREEN).
+     */
+    setBrowseState(payload) {
+      mockSetBrowseState(payload)
+      if (payload.freshness !== undefined) _mockFolderFreshness.value = payload.freshness
+      if (payload.refreshedAt !== undefined) _mockLastRefreshedAt.value = payload.refreshedAt
+      if (payload.caps !== undefined) _mockCapabilities.value = payload.caps
+      if (payload.byteAvail !== undefined) _mockByteAvailability.value = payload.byteAvail
+    },
     defaultDisplayName: (c) => c.provider,
   }),
   saveLastFolder: vi.fn(),
@@ -63,10 +86,16 @@ vi.mock('../../stores/toast.js', () => ({
 }))
 
 // Network boundary: stub only the API layer
+// D-13: testCloudConnection must be defined in mock so no-probe-on-navigation
+// tests can assert it was NOT called during ordinary folder browse (T-13-30).
 vi.mock('../../api/client.js', () => ({
   getCloudFoldersByConnectionId: vi.fn().mockResolvedValue({ items: [], capabilities: null }),
   uploadToCloud: vi.fn(),
   listCloudConnections: vi.fn().mockResolvedValue({ items: [] }),
+  testCloudConnection: vi.fn(),
+  openCloudFile: vi.fn(),
+  downloadCloudFile: vi.fn(),
+  uploadCloudFile: vi.fn(),
 }))
 
 import CloudFolderView from '../CloudFolderView.vue'
@@ -161,6 +190,11 @@ beforeEach(() => {
   setActivePinia(createPinia())
   vi.clearAllMocks()
   sessionStorage.clear()
+  // Reset reactive mock store state between tests (D-12 health state isolation)
+  _mockFolderFreshness.value = null
+  _mockLastRefreshedAt.value = null
+  _mockCapabilities.value = null
+  _mockByteAvailability.value = null
 })
 
 afterEach(() => {