diff --git a/src-tauri/src/core/threads.rs b/src-tauri/src/core/threads.rs
index e4b8f2e52..34b0bbd77 100644
--- a/src-tauri/src/core/threads.rs
+++ b/src-tauri/src/core/threads.rs
@@ -278,8 +278,10 @@ pub async fn create_message<R: Runtime>(
     ensure_thread_dir_exists(app_handle.clone(), &thread_id)?;
     let path = get_messages_path(app_handle.clone(), &thread_id);
 
-    let uuid = Uuid::new_v4().to_string();
-    message["id"] = serde_json::Value::String(uuid);
+    if message.get("id").is_none() {
+        let uuid = Uuid::new_v4().to_string();
+        message["id"] = serde_json::Value::String(uuid);
+    }
 
     // Acquire per-thread lock before writing
     {
@@ -292,7 +294,7 @@ pub async fn create_message<R: Runtime>(
 
         let _guard = lock.lock().await;
 
-        let mut file = fs::OpenOptions::new()
+        let mut file: File = fs::OpenOptions::new()
             .create(true)
             .append(true)
             .open(path)
@@ -354,21 +356,34 @@ pub async fn modify_message<R: Runtime>(
 
 /// Deletes a message from a thread's messages.jsonl file by message ID.
 /// Rewrites the entire messages.jsonl file for the thread.
+/// Uses a per-thread async lock to prevent race conditions and ensure file consistency.
 #[command]
 pub async fn delete_message<R: Runtime>(
     app_handle: tauri::AppHandle<R>,
     thread_id: String,
     message_id: String,
 ) -> Result<(), String> {
-    let mut messages = list_messages(app_handle.clone(), thread_id.clone()).await?;
-    messages.retain(|m| m.get("id").and_then(|v| v.as_str()) != Some(message_id.as_str()));
+    // Acquire per-thread lock before modifying
+    {
+        let mut locks = MESSAGE_LOCKS.lock().await;
+        let lock = locks
+            .entry(thread_id.to_string())
+            .or_insert_with(|| Arc::new(Mutex::new(())))
+            .clone();
+        drop(locks); // Release the map lock before awaiting the file lock
 
-    // Rewrite remaining messages
-    let path = get_messages_path(app_handle.clone(), &thread_id);
-    let mut file = File::create(path).map_err(|e| e.to_string())?;
-    for msg in messages {
-        let data = serde_json::to_string(&msg).map_err(|e| e.to_string())?;
-        writeln!(file, "{}", data).map_err(|e| e.to_string())?;
+        let _guard = lock.lock().await;
+
+        let mut messages = list_messages(app_handle.clone(), thread_id.clone()).await?;
+        messages.retain(|m| m.get("id").and_then(|v| v.as_str()) != Some(message_id.as_str()));
+
+        // Rewrite remaining messages
+        let path = get_messages_path(app_handle.clone(), &thread_id);
+        let mut file = File::create(path).map_err(|e| e.to_string())?;
+        for msg in messages {
+            let data = serde_json::to_string(&msg).map_err(|e| e.to_string())?;
+            writeln!(file, "{}", data).map_err(|e| e.to_string())?;
+        }
     }
 
     Ok(())
@@ -441,7 +456,7 @@ pub async fn modify_thread_assistant<R: Runtime>(
         serde_json::from_str(&data).map_err(|e| e.to_string())?
     };
     let assistant_id = assistant
-        .get("id")
+        .get("assistant_id")
         .and_then(|v| v.as_str())
         .ok_or("Missing assistant_id")?;
     if let Some(assistants) = thread
diff --git a/web/containers/Providers/ModelHandler.tsx b/web/containers/Providers/ModelHandler.tsx
index a1fffa011..9590e5048 100644
--- a/web/containers/Providers/ModelHandler.tsx
+++ b/web/containers/Providers/ModelHandler.tsx
@@ -216,76 +216,66 @@ export default function ModelHandler() {
             model: activeModelRef.current?.name,
           }
         })
-        return
-      } else if (
-        message.status === MessageStatus.Error &&
-        activeModelRef.current?.engine &&
-        engines &&
-        isLocalEngine(engines, activeModelRef.current.engine)
-      ) {
-        extensionManager
-          .get<ModelExtension>(ExtensionTypeEnum.Model)
-          ?.isModelLoaded(activeModelRef.current?.id as string)
-          .then((isLoaded) => {
-            if (!isLoaded) {
-              setActiveModel(undefined)
-              setStateModel({
-                state: 'start',
-                loading: false,
-                model: undefined,
-              })
-            }
-          })
-      }
-      // Mark the thread as not waiting for response
-      updateThreadWaiting(message.thread_id, false)
+      } else {
+        // Mark the thread as not waiting for response
+        updateThreadWaiting(message.thread_id, false)
 
-      setIsGeneratingResponse(false)
+        setIsGeneratingResponse(false)
 
-      const thread = threadsRef.current?.find((e) => e.id == message.thread_id)
-      if (!thread) return
+        const thread = threadsRef.current?.find(
+          (e) => e.id == message.thread_id
+        )
+        if (!thread) return
 
-      const messageContent = message.content[0]?.text?.value
+        const messageContent = message.content[0]?.text?.value
 
-      const metadata = {
-        ...thread.metadata,
-        ...(messageContent && { lastMessage: messageContent }),
-        updated_at: Date.now(),
-      }
+        const metadata = {
+          ...thread.metadata,
+          ...(messageContent && { lastMessage: messageContent }),
+          updated_at: Date.now(),
+        }
 
-      updateThread({
-        ...thread,
-        metadata,
-      })
-
-      extensionManager
-        .get<ConversationalExtension>(ExtensionTypeEnum.Conversational)
-        ?.modifyThread({
+        updateThread({
           ...thread,
           metadata,
         })
 
-      // Update message's metadata with token usage
-      message.metadata = {
-        ...message.metadata,
-        token_speed: tokenSpeedRef.current?.tokenSpeed,
-        model: activeModelRef.current?.name,
-      }
+        extensionManager
+          .get<ConversationalExtension>(ExtensionTypeEnum.Conversational)
+          ?.modifyThread({
+            ...thread,
+            metadata,
+          })
 
-      if (message.status === MessageStatus.Error) {
+        // Update message's metadata with token usage
         message.metadata = {
           ...message.metadata,
-          error: message.content[0]?.text?.value,
-          error_code: message.error_code,
+          token_speed: tokenSpeedRef.current?.tokenSpeed,
+          model: activeModelRef.current?.name,
         }
+
+        if (message.status === MessageStatus.Error) {
+          message.metadata = {
+            ...message.metadata,
+            error: message.content[0]?.text?.value,
+            error_code: message.error_code,
+          }
+          // Unassign active model if any
+          setActiveModel(undefined)
+          setStateModel({
+            state: 'start',
+            loading: false,
+            model: undefined,
+          })
+        }
+
+        extensionManager
+          .get<ConversationalExtension>(ExtensionTypeEnum.Conversational)
+          ?.createMessage(message)
+
+        // Attempt to generate the title of the Thread when needed
+        generateThreadTitle(message, thread)
       }
-
-      extensionManager
-        .get<ConversationalExtension>(ExtensionTypeEnum.Conversational)
-        ?.createMessage(message)
-
-      // Attempt to generate the title of the Thread when needed
-      generateThreadTitle(message, thread)
     },
     // eslint-disable-next-line react-hooks/exhaustive-deps
     [setIsGeneratingResponse, updateMessage, updateThread, updateThreadWaiting]
diff --git a/web/hooks/useDeleteThread.ts b/web/hooks/useDeleteThread.ts
index 59aa3a83b..d0c7cac1a 100644
--- a/web/hooks/useDeleteThread.ts
+++ b/web/hooks/useDeleteThread.ts
@@ -38,12 +38,13 @@ export default function useDeleteThread() {
         ?.listMessages(threadId)
         .catch(console.error)
       if (messages) {
-        messages.forEach((message) => {
-          extensionManager
+        for (const message of messages) {
+          await extensionManager
             .get<ConversationalExtension>(ExtensionTypeEnum.Conversational)
             ?.deleteMessage(threadId, message.id)
             .catch(console.error)
-        })
+        }
+       
         const thread = threads.find((e) => e.id === threadId)
         if (thread) {
           const updatedThread = {
diff --git a/web/hooks/useSendChatMessage.ts b/web/hooks/useSendChatMessage.ts
index bfe3a601f..49e0d3e5b 100644
--- a/web/hooks/useSendChatMessage.ts
+++ b/web/hooks/useSendChatMessage.ts
@@ -135,12 +135,16 @@ export default function useSendChatMessage() {
   ) => {
     if (!message || message.trim().length === 0) return
 
-    if (!activeThreadRef.current || !activeAssistantRef.current) {
+    const activeThread = activeThreadRef.current
+    const activeAssistant = activeAssistantRef.current
+    const activeModel = selectedModelRef.current
+
+    if (!activeThread || !activeAssistant) {
       console.error('No active thread or assistant')
       return
     }
 
-    if (selectedModelRef.current?.id === undefined) {
+    if (!activeModel?.id) {
       setModelDropdownState(true)
       return
     }
@@ -153,7 +157,7 @@ export default function useSendChatMessage() {
 
     const prompt = message.trim()
 
-    updateThreadWaiting(activeThreadRef.current.id, true)
+    updateThreadWaiting(activeThread.id, true)
     setCurrentPrompt('')
     setEditPrompt('')
 
@@ -164,15 +168,14 @@ export default function useSendChatMessage() {
       base64Blob = await compressImage(base64Blob, 512)
     }
 
-    const modelRequest =
-      selectedModelRef?.current ?? activeAssistantRef.current?.model
+    const modelRequest = selectedModel ?? activeAssistant.model
 
     // Fallback support for previous broken threads
-    if (activeAssistantRef.current?.model?.id === '*') {
-      activeAssistantRef.current.model = {
-        id: modelRequest.id,
-        settings: modelRequest.settings,
-        parameters: modelRequest.parameters,
+    if (activeAssistant.model?.id === '*') {
+      activeAssistant.model = {
+        id: activeModel.id,
+        settings: activeModel.settings,
+        parameters: activeModel.parameters,
       }
     }
     if (runtimeParams.stream == null) {
@@ -187,7 +190,7 @@ export default function useSendChatMessage() {
         settings: settingParams,
         parameters: runtimeParams,
       },
-      activeThreadRef.current,
+      activeThread,
       messages ?? currentMessages,
       (await window.core.api.getTools())?.map((tool: ModelTool) => ({
         type: 'function' as const,
@@ -198,7 +201,7 @@ export default function useSendChatMessage() {
           strict: false,
         },
       }))
-    ).addSystemMessage(activeAssistantRef.current?.instructions)
+    ).addSystemMessage(activeAssistant.instructions)
 
     requestBuilder.pushMessage(prompt, base64Blob, fileUpload)
 
@@ -211,10 +214,10 @@ export default function useSendChatMessage() {
 
     // Update thread state
     const updatedThread: Thread = {
-      ...activeThreadRef.current,
+      ...activeThread,
       updated: newMessage.created_at,
       metadata: {
-        ...activeThreadRef.current.metadata,
+        ...activeThread.metadata,
         lastMessage: prompt,
       },
     }
@@ -237,17 +240,16 @@ export default function useSendChatMessage() {
     }
 
     // Start Model if not started
-    const modelId =
-      selectedModelRef.current?.id ?? activeAssistantRef.current?.model.id
+    const modelId = selectedModel?.id ?? activeAssistantRef.current?.model.id
 
     if (base64Blob) {
       setFileUpload(undefined)
     }
 
-    if (modelRef.current?.id !== modelId && modelId) {
+    if (activeModel?.id !== modelId && modelId) {
       const error = await startModel(modelId).catch((error: Error) => error)
       if (error) {
-        updateThreadWaiting(activeThreadRef.current.id, false)
+        updateThreadWaiting(activeThread.id, false)
         return
       }
     }
@@ -271,8 +273,8 @@ export default function useSendChatMessage() {
         const message: ThreadMessage = {
           id: messageId,
           object: 'message',
-          thread_id: activeThreadRef.current.id,
-          assistant_id: activeAssistantRef.current.assistant_id,
+          thread_id: activeThread.id,
+          assistant_id: activeAssistant.assistant_id,
           role: ChatCompletionRole.Assistant,
           content: [],
           metadata: {
@@ -317,6 +319,8 @@ export default function useSendChatMessage() {
             message
           )
         }
+        message.status = MessageStatus.Ready
+        events.emit(MessageEvent.OnMessageUpdate, message)
       }
     } else {
       // Request for inference
@@ -504,8 +508,6 @@ export default function useSendChatMessage() {
         events.emit(MessageEvent.OnMessageUpdate, message)
       }
     }
-    message.status = MessageStatus.Ready
-    events.emit(MessageEvent.OnMessageUpdate, message)
   }
 
   return {
diff --git a/web/screens/Thread/ThreadCenterPanel/TextMessage/ToolCallBlock.tsx b/web/screens/Thread/ThreadCenterPanel/TextMessage/ToolCallBlock.tsx
index 3ebfba7d3..818af5b4d 100644
--- a/web/screens/Thread/ThreadCenterPanel/TextMessage/ToolCallBlock.tsx
+++ b/web/screens/Thread/ThreadCenterPanel/TextMessage/ToolCallBlock.tsx
@@ -46,7 +46,7 @@ const ToolCallBlock = ({ id, name, result, loading }: Props) => {
 
         {isExpanded && (
           <div className="mt-2 overflow-x-hidden pl-6 text-[hsla(var(--text-secondary))]">
-            <span>{result.trim()} </span>
+            <span>{result ?? ''} </span>
           </div>
         )}
       </div>