diff --git a/src/topic_description.rs b/src/topic_description.rs
index 6d15666..ea04462 100644
--- a/src/topic_description.rs
+++ b/src/topic_description.rs
@@ -4,15 +4,17 @@ pub async fn generate_topic_description(
     provider: &dyn LLMProvider,
     first_user_message: &str,
 ) -> Result<String, Box<dyn std::error::Error + Send + Sync>> {
-    let prompt = format!(
-        "请根据用户的第一句话，用简短的词语（不超过15字）描述这个对话的主题或意图。只输出描述内容，不要其他解释。\n\n用户消息：{}",
-        first_user_message
-    );
+    let system_prompt = "你是一个话题摘要助手。请根据用户的第一句话，用简短的词语（不超过15字）描述这个对话的主题或意图。只输出描述内容，不要任何解释、标点或前缀。";
+
+    let user_prompt = format!("用户消息：{}", first_user_message);
 
     let request = ChatCompletionRequest {
-        messages: vec![Message::user(prompt)],
-        temperature: Some(0.3),
-        max_tokens: Some(50),
+        messages: vec![
+            Message::system(system_prompt),
+            Message::user(user_prompt),
+        ],
+        temperature: Some(0.0),
+        max_tokens: Some(1024), // 给 reasoning 模型留足思考空间
         tools: None,
     };
 
@@ -20,6 +22,24 @@ pub async fn generate_topic_description(
     let description = response.content.trim().to_string();
 
     if description.is_empty() {
+        // 回退：reasoning 模型有时把所有 token 都消耗在推理上，content 为空
+        // 此时尝试从 reasoning_content 中提取最后一行有意义的内容作为描述
+        if let Some(ref reasoning) = response.reasoning_content {
+            let fallback: String = reasoning
+                .lines()
+                .rev()
+                .find(|line| {
+                    let trimmed = line.trim();
+                    !trimmed.is_empty() && trimmed.len() <= 50
+                })
+                .unwrap_or("")
+                .trim()
+                .to_string();
+            if !fallback.is_empty() {
+                let truncated: String = fallback.chars().take(50).collect();
+                return Ok(truncated);
+            }
+        }
         return Err("LLM returned empty description".into());
     }
 
diff --git a/web/src/App.tsx b/web/src/App.tsx
index e58a531..c4e0795 100644
--- a/web/src/App.tsx
+++ b/web/src/App.tsx
@@ -202,7 +202,7 @@ function App() {
         let cmd: Command
         switch (command) {
           case 'new':
-            cmd = { type: 'create_session', title: args.join(' ') || undefined }
+            cmd = createTopic(args.join(' ') || undefined)
             break
           case 'list':
             cmd = { type: 'list_sessions', include_archived: args[0] === 'all' }
diff --git a/web/src/hooks/useChat.ts b/web/src/hooks/useChat.ts
index 93b0b6e..ce3d834 100644
--- a/web/src/hooks/useChat.ts
+++ b/web/src/hooks/useChat.ts
@@ -158,6 +158,7 @@ export function useChat(): UseChatReturn {
   const schedulerViewRef = useRef<SchedulerJobView | null>(null)
   const topicsRef = useRef<Topic[]>([])
   const selectedTopicRef = useRef<string | null>(null)
+  const pendingNewTopicRef = useRef(false)
 
   const isConnected = useMemo(() => connectionId !== null, [connectionId])
   const selectedSession = useMemo(
@@ -402,7 +403,15 @@ export function useChat(): UseChatReturn {
         }))
         setTopics(newTopics)
 
-        // 默认选中第一个 Topic（如果没有选中）
+        // 新建话题后自动聚焦到新话题（列表按 last_active_at DESC 排序，第一个即最新）
+        if (pendingNewTopicRef.current) {
+          pendingNewTopicRef.current = false
+          if (newTopics.length > 0) {
+            setSelectedTopic(newTopics[0].id)
+            setMessages([])
+          }
+        }
+
         setIsLoading(false)
         break
       }
@@ -592,6 +601,7 @@ export function useChat(): UseChatReturn {
   }, [])
 
   const createTopic = useCallback((title?: string): Command => {
+    pendingNewTopicRef.current = true
     return {
       type: 'create_session',
       title: title || `话题 ${new Date().toLocaleString('zh-CN', { month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' })}`,