fix: assistant with last used and fix metadata (#5955)

* fix: assistant with last used and fix metadata

* chore: revert instruction and desc

* chore: fix current assistant state

* chore: updae metadata message assistant

* chore: update test case

web-app/src/constants/localStorage.ts

@@ -18,4 +18,5 @@ export const localStorageKey = {
   toolAvailability: 'tool-availability',
   mcpGlobalPermissions: 'mcp-global-permissions',
   lastUsedModel: 'last-used-model',
+  lastUsedAssistant: 'last-used-assistant',
 }

web-app/src/hooks/__tests__/useAppState.test.ts

@@ -11,7 +11,8 @@ vi.mock('../useAssistant', () => ({
     })),
     {
       getState: vi.fn(() => ({
-        currentAssistant: { id: 'test-assistant', name: 'Test Assistant' }
+        currentAssistant: { id: 'test-assistant', name: 'Test Assistant' },
+        assistants: [{ id: 'test-assistant', name: 'Test Assistant' }]
       }))
     }
   )

web-app/src/hooks/__tests__/useChat.test.ts

@@ -11,7 +11,8 @@ vi.mock('../usePrompt', () => ({
 }))
 
 vi.mock('../useAppState', () => ({
-  useAppState: vi.fn(() => ({
+  useAppState: Object.assign(
+    vi.fn(() => ({
       tools: [],
       updateTokenSpeed: vi.fn(),
       resetTokenSpeed: vi.fn(),
@@ -20,10 +21,21 @@ vi.mock('../useAppState', () => ({
       updateLoadingModel: vi.fn(),
       setAbortController: vi.fn(),
     })),
+    {
+      getState: vi.fn(() => ({
+        tokenSpeed: { tokensPerSecond: 10 },
+      }))
+    }
+  ),
 }))
 
 vi.mock('../useAssistant', () => ({
   useAssistant: vi.fn(() => ({
+    assistants: [{
+      id: 'test-assistant',
+      instructions: 'test instructions',
+      parameters: { stream: true },
+    }],
     currentAssistant: {
       id: 'test-assistant',
       instructions: 'test instructions',
@@ -88,6 +100,12 @@ vi.mock('../useModelContextApproval', () => ({
   })),
 }))
 
+vi.mock('../useModelLoad', () => ({
+  useModelLoad: vi.fn(() => ({
+    setModelLoadError: vi.fn(),
+  })),
+}))
+
 vi.mock('@tanstack/react-router', () => ({
   useRouter: vi.fn(() => ({
     navigate: vi.fn(),
@@ -96,6 +114,7 @@ vi.mock('@tanstack/react-router', () => ({
 
 vi.mock('@/lib/completion', () => ({
   emptyThreadContent: { thread_id: 'test-thread', content: '' },
+  extractToolCall: vi.fn(),
   newUserThreadContent: vi.fn(() => ({ thread_id: 'test-thread', content: 'user message' })),
   newAssistantThreadContent: vi.fn(() => ({ thread_id: 'test-thread', content: 'assistant message' })),
   sendCompletion: vi.fn(),

web-app/src/hooks/useAppState.ts

@@ -35,6 +35,12 @@ export const useAppState = create<AppState>()((set) => ({
   tokenSpeed: undefined,
   currentToolCall: undefined,
   updateStreamingContent: (content: ThreadMessage | undefined) => {
+    const assistants = useAssistant.getState().assistants
+    const currentAssistant = useAssistant.getState().currentAssistant
+
+    const selectedAssistant =
+      assistants.find((a) => a.id === currentAssistant.id) || assistants[0]
+
     set(() => ({
       streamingContent: content
         ? {
@@ -42,7 +48,7 @@ export const useAppState = create<AppState>()((set) => ({
             created_at: content.created_at || Date.now(),
             metadata: {
               ...content.metadata,
-              assistant: useAssistant.getState().currentAssistant,
+              assistant: selectedAssistant,
             },
           }
         : undefined,

web-app/src/hooks/useAssistant.ts

@@ -1,6 +1,7 @@
 import { createAssistant, deleteAssistant } from '@/services/assistants'
 import { Assistant as CoreAssistant } from '@janhq/core'
 import { create } from 'zustand'
+import { localStorageKey } from '@/constants/localStorage'
 
 interface AssistantState {
   assistants: Assistant[]
@@ -8,8 +9,29 @@ interface AssistantState {
   addAssistant: (assistant: Assistant) => void
   updateAssistant: (assistant: Assistant) => void
   deleteAssistant: (id: string) => void
-  setCurrentAssistant: (assistant: Assistant) => void
+  setCurrentAssistant: (assistant: Assistant, saveToStorage?: boolean) => void
   setAssistants: (assistants: Assistant[]) => void
+  getLastUsedAssistant: () => string | null
+  setLastUsedAssistant: (assistantId: string) => void
+  initializeWithLastUsed: () => void
+}
+
+// Helper functions for localStorage
+const getLastUsedAssistantId = (): string | null => {
+  try {
+    return localStorage.getItem(localStorageKey.lastUsedAssistant)
+  } catch (error) {
+    console.debug('Failed to get last used assistant from localStorage:', error)
+    return null
+  }
+}
+
+const setLastUsedAssistantId = (assistantId: string) => {
+  try {
+    localStorage.setItem(localStorageKey.lastUsedAssistant, assistantId)
+  } catch (error) {
+    console.debug('Failed to set last used assistant in localStorage:', error)
+  }
 }
 
 export const defaultAssistant: Assistant = {
@@ -51,17 +73,52 @@ export const useAssistant = create<AssistantState>()((set, get) => ({
     })
   },
   deleteAssistant: (id) => {
+    const state = get()
     deleteAssistant(
-      get().assistants.find((e) => e.id === id) as unknown as CoreAssistant
+      state.assistants.find((e) => e.id === id) as unknown as CoreAssistant
     ).catch((error) => {
       console.error('Failed to delete assistant:', error)
     })
-    set({ assistants: get().assistants.filter((a) => a.id !== id) })
+
+    // Check if we're deleting the current assistant
+    const wasCurrentAssistant = state.currentAssistant.id === id
+
+    set({ assistants: state.assistants.filter((a) => a.id !== id) })
+
+    // If the deleted assistant was current, fallback to default and update localStorage
+    if (wasCurrentAssistant) {
+      set({ currentAssistant: defaultAssistant })
+      setLastUsedAssistantId(defaultAssistant.id)
+    }
   },
-  setCurrentAssistant: (assistant) => {
+  setCurrentAssistant: (assistant, saveToStorage = true) => {
     set({ currentAssistant: assistant })
+    if (saveToStorage) {
+      setLastUsedAssistantId(assistant.id)
+    }
   },
   setAssistants: (assistants) => {
     set({ assistants })
   },
+  getLastUsedAssistant: () => {
+    return getLastUsedAssistantId()
+  },
+  setLastUsedAssistant: (assistantId) => {
+    setLastUsedAssistantId(assistantId)
+  },
+  initializeWithLastUsed: () => {
+    const lastUsedId = getLastUsedAssistantId()
+    if (lastUsedId) {
+      const lastUsedAssistant = get().assistants.find(
+        (a) => a.id === lastUsedId
+      )
+      if (lastUsedAssistant) {
+        set({ currentAssistant: lastUsedAssistant })
+      } else {
+        // Fallback to default if last used assistant was deleted
+        set({ currentAssistant: defaultAssistant })
+        setLastUsedAssistantId(defaultAssistant.id)
+      }
+    }
+  },
 }))

web-app/src/hooks/useChat.ts

@@ -45,7 +45,7 @@ export const useChat = () => {
     updateLoadingModel,
     setAbortController,
   } = useAppState()
-  const { currentAssistant } = useAssistant()
+  const { assistants, currentAssistant } = useAssistant()
   const { updateProvider } = useModelProvider()
 
   const { approvedTools, showApprovalModal, allowAllMCPPermissions } =
@@ -74,6 +74,9 @@ export const useChat = () => {
     return provider?.provider || selectedProvider
   }, [provider, selectedProvider])
 
+  const selectedAssistant =
+    assistants.find((a) => a.id === currentAssistant.id) || assistants[0]
+
   useEffect(() => {
     function setTools() {
       getTools().then((data: MCPTool[]) => {
@@ -92,6 +95,7 @@ export const useChat = () => {
 
   const getCurrentThread = useCallback(async () => {
     let currentThread = retrieveThread()
+
     if (!currentThread) {
       currentThread = await createThread(
         {
@@ -99,7 +103,7 @@ export const useChat = () => {
           provider: selectedProvider,
         },
         prompt,
-        currentAssistant
+        selectedAssistant
       )
       router.navigate({
         to: route.threadsDetail,
@@ -114,7 +118,7 @@ export const useChat = () => {
     router,
     selectedModel?.id,
     selectedProvider,
-    currentAssistant,
+    selectedAssistant,
   ])
 
   const restartModel = useCallback(
@@ -402,6 +406,7 @@ export const useChat = () => {
             accumulatedText,
             {
               tokenSpeed: useAppState.getState().tokenSpeed,
+              assistant: currentAssistant,
             }
           )
 

web-app/src/hooks/useMessages.ts

@@ -28,19 +28,18 @@ export const useMessages = create<MessageState>()((set, get) => ({
     }))
   },
   addMessage: (message) => {
+    const assistants = useAssistant.getState().assistants
     const currentAssistant = useAssistant.getState().currentAssistant
+
+    const selectedAssistant =
+      assistants.find((a) => a.id === currentAssistant.id) || assistants[0]
+
     const newMessage = {
       ...message,
       created_at: message.created_at || Date.now(),
       metadata: {
         ...message.metadata,
-        assistant: {
+        assistant: selectedAssistant,
-          id: currentAssistant?.id || '',
-          name: currentAssistant?.name || '',
-          avatar: currentAssistant?.avatar || '',
-          instructions: currentAssistant?.instructions || '',
-          parameters: currentAssistant?.parameters || '',
-        },
       },
     }
     createMessage(newMessage).then((createdMessage) => {

web-app/src/providers/DataProvider.tsx

@@ -24,7 +24,7 @@ export function DataProvider() {
   const { setMessages } = useMessages()
   const { checkForUpdate } = useAppUpdater()
   const { setServers } = useMCPServers()
-  const { setAssistants } = useAssistant()
+  const { setAssistants, initializeWithLastUsed } = useAssistant()
   const { setThreads } = useThreads()
   const navigate = useNavigate()
 
@@ -37,6 +37,7 @@ export function DataProvider() {
         // Only update assistants if we have valid data
         if (data && Array.isArray(data) && data.length > 0) {
           setAssistants(data as unknown as Assistant[])
+          initializeWithLastUsed()
         }
       })
       .catch((error) => {