diff --git a/mateclaw-ui/src/utils/chatRouteHydration.ts b/mateclaw-ui/src/utils/chatRouteHydration.ts
new file mode 100644
index 00000000..78c17eee
--- /dev/null
+++ b/mateclaw-ui/src/utils/chatRouteHydration.ts
@@ -0,0 +1,25 @@
+type IdLike = string | number
+
+interface RouteHydrationAgent {
+  id: IdLike
+}
+
+interface RouteHydrationConversation {
+  conversationId: string
+}
+
+export function resolveRouteHydrationQuery(options: {
+  routeAgentId?: string
+  routeConversationId?: string
+  agents: RouteHydrationAgent[]
+  conversations: RouteHydrationConversation[]
+}): { agentId: string; conversationId: string } {
+  let agentId = options.routeAgentId || ''
+  const conversationId = options.routeConversationId || ''
+
+  if (agentId && options.agents.length > 0 && !options.agents.some(a => String(a.id) === agentId)) {
+    agentId = ''
+  }
+
+  return { agentId, conversationId }
+}
diff --git a/mateclaw-ui/src/views/ChatConsole.vue b/mateclaw-ui/src/views/ChatConsole.vue
index 5166d99d..5c2ad122 100644
--- a/mateclaw-ui/src/views/ChatConsole.vue
+++ b/mateclaw-ui/src/views/ChatConsole.vue
@@ -291,6 +291,7 @@ import { useChat } from '@/composables/chat/useChat'
 import RunOverviewPanel from '@/components/chat/RunOverviewPanel.vue'
 import { reconstructErrorInfo } from '@/types/chatError'
 import { reconcileMessages, extractMessages } from '@/utils/messageReconcile'
+import { resolveRouteHydrationQuery } from '@/utils/chatRouteHydration'
 import type { Conversation, Agent, ModelConfig, ProviderInfo, ActiveModelsInfo, ChatAttachment, MessageContentPart, Message, ToolCallMeta } from '@/types'
 
 // 导入组件化组件
@@ -1617,24 +1618,12 @@ async function refreshCurrentConversationMessages(conversationId: string) {
 }
 
 async function hydrateStateFromRoute() {
-  let agentId = route.query.agentId ? String(route.query.agentId) : ''
-  let conversationId = String(route.query.conversationId || '')
-
-  // The URL can outlive its workspace: switching workspaces remounts this view
-  // (via the router-view key) but keeps the query string, so agentId /
-  // conversationId may still point at entities of the previous workspace. An
-  // agentId missing from the workspace-scoped agent list is such a leftover —
-  // drop it so the default-select below picks a real employee instead of the
-  // picker rendering the unresolvable raw id.
-  if (agentId && agents.value.length > 0 && !agents.value.some(a => String(a.id) === agentId)) {
-    agentId = ''
-    // Only follow the paired conversationId when it resolves locally (e.g. a
-    // Sessions-page jump within this workspace); otherwise it is equally stale
-    // and would attach the fallback agent to a foreign conversation.
-    if (!conversations.value.some(conv => conv.conversationId === conversationId)) {
-      conversationId = ''
-    }
-  }
+  const { agentId, conversationId } = resolveRouteHydrationQuery({
+    routeAgentId: route.query.agentId ? String(route.query.agentId) : '',
+    routeConversationId: String(route.query.conversationId || ''),
+    agents: agents.value,
+    conversations: conversations.value,
+  })
 
   if (agentId && agentId !== String(selectedAgentId.value)) {
     selectedAgentId.value = agentId
diff --git a/mateclaw-ui/src/views/__tests__/chatConsoleRouteHydration.test.ts b/mateclaw-ui/src/views/__tests__/chatConsoleRouteHydration.test.ts
new file mode 100644
index 00000000..2ef202bb
--- /dev/null
+++ b/mateclaw-ui/src/views/__tests__/chatConsoleRouteHydration.test.ts
@@ -0,0 +1,36 @@
+// @vitest-environment happy-dom
+import { describe, expect, it } from 'vitest'
+import { resolveRouteHydrationQuery } from '@/utils/chatRouteHydration'
+
+const agents = [{ id: 'agent-visible' }]
+const conversations = [{ conversationId: 'conv-listed' }]
+
+describe('resolveRouteHydrationQuery', () => {
+  it('keeps a deep-linked child conversation even when it is not in the sidebar list', () => {
+    const result = resolveRouteHydrationQuery({
+      routeAgentId: 'agent-deleted-or-hidden',
+      routeConversationId: 'team-task-finished',
+      agents,
+      conversations,
+    })
+
+    expect(result).toEqual({
+      agentId: '',
+      conversationId: 'team-task-finished',
+    })
+  })
+
+  it('keeps valid route agent and conversation ids unchanged', () => {
+    const result = resolveRouteHydrationQuery({
+      routeAgentId: 'agent-visible',
+      routeConversationId: 'conv-listed',
+      agents,
+      conversations,
+    })
+
+    expect(result).toEqual({
+      agentId: 'agent-visible',
+      conversationId: 'conv-listed',
+    })
+  })
+})