diff --git a/packages/server/src/agent/adapter.ts b/packages/server/src/agent/adapter.ts
index a8e171e..7910d5d 100644
--- a/packages/server/src/agent/adapter.ts
+++ b/packages/server/src/agent/adapter.ts
@@ -529,6 +529,7 @@ export async function processMessage(
         text: result.text,
         hasToolCalls,
         messageCount: result.messages.length,
+        agentName: options?.agentMode || 'build',
       },
     });
 
diff --git a/packages/ui/src/api/types.ts b/packages/ui/src/api/types.ts
index a0eeb01..b2280c0 100644
--- a/packages/ui/src/api/types.ts
+++ b/packages/ui/src/api/types.ts
@@ -95,6 +95,8 @@ export interface Message {
     model?: string;
     stepCount?: number;
     totalTokens?: number;
+    /** 生成此消息的 Agent 名称 */
+    agentName?: string;
   };
 }
 
diff --git a/packages/ui/src/components/ChatMessage.tsx b/packages/ui/src/components/ChatMessage.tsx
index 8760025..8e66269 100644
--- a/packages/ui/src/components/ChatMessage.tsx
+++ b/packages/ui/src/components/ChatMessage.tsx
@@ -19,6 +19,7 @@ import { motion, AnimatePresence } from 'framer-motion';
 import { useState, forwardRef } from 'react';
 import { cn } from '../utils/cn';
 import { fadeInUp, smoothTransition } from '../utils/animations';
+import { getAgentDisplayName } from '../utils/agent';
 import { Markdown } from './Markdown';
 import { FileMentionText } from './FileMentionTag';
 import type { Message, ToolCallInfo, ToolCallStatus, ToolMessagePart } from '../api/types.js';
@@ -137,7 +138,7 @@ export const ChatMessage = forwardRef<HTMLDivElement, ChatMessageProps>(
         <div className="flex-1 min-w-0 overflow-hidden">
           <div className="flex items-center justify-between mb-1">
             <span className="text-sm text-fg-muted">
-              {isUser ? 'You' : 'AI Assistant'}
+              {isUser ? 'You' : getAgentDisplayName(message.metadata?.agentName)}
             </span>
             <button
               onClick={handleCopy}
@@ -156,9 +157,11 @@ export const ChatMessage = forwardRef<HTMLDivElement, ChatMessageProps>(
 
 interface StreamingMessageProps {
   content: string;
+  /** 当前 Agent 名称 */
+  agentName?: string;
 }
 
-export function StreamingMessage({ content }: StreamingMessageProps) {
+export function StreamingMessage({ content, agentName }: StreamingMessageProps) {
   return (
     <motion.div
       initial={{ opacity: 0, y: 10 }}
@@ -170,7 +173,7 @@ export function StreamingMessage({ content }: StreamingMessageProps) {
         <Bot size={18} />
       </div>
       <div className="flex-1 min-w-0 overflow-hidden">
-        <div className="text-sm text-fg-muted mb-1">AI Assistant</div>
+        <div className="text-sm text-fg-muted mb-1">{getAgentDisplayName(agentName)}</div>
         <div className="message-content text-fg-secondary">
           <Markdown content={content} />
           <motion.span
@@ -184,7 +187,12 @@ export function StreamingMessage({ content }: StreamingMessageProps) {
   );
 }
 
-export function TypingIndicator() {
+interface TypingIndicatorProps {
+  /** 当前 Agent 名称 */
+  agentName?: string;
+}
+
+export function TypingIndicator({ agentName }: TypingIndicatorProps) {
   return (
     <motion.div
       initial={{ opacity: 0, y: 10 }}
@@ -196,7 +204,7 @@ export function TypingIndicator() {
         <Bot size={18} />
       </div>
       <div className="flex-1">
-        <div className="text-sm text-fg-muted mb-1">AI Assistant</div>
+        <div className="text-sm text-fg-muted mb-1">{getAgentDisplayName(agentName)}</div>
         <div className="flex items-center gap-1 h-6">
           {[0, 1, 2].map((i) => (
             <motion.span
diff --git a/packages/ui/src/hooks/useChat.ts b/packages/ui/src/hooks/useChat.ts
index 1617636..e773e63 100644
--- a/packages/ui/src/hooks/useChat.ts
+++ b/packages/ui/src/hooks/useChat.ts
@@ -36,6 +36,8 @@ interface ChatState {
   agentMode: AgentModeType;
   /** 是否自动授权文件写入/编辑 (会话级别) */
   autoApprove: boolean;
+  /** 当前正在执行的 Agent 名称 */
+  currentAgent: string;
 }
 
 export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdated, onConfigError }: UseChatOptions) {
@@ -47,6 +49,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
     permissionRequest: null,
     agentMode: 'build',
     autoApprove: false,
+    currentAgent: 'build',
   });
 
   const wsRef = useRef<WebSocket | null>(null);
@@ -138,6 +141,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                 timestamp: new Date().toISOString(),
                 parts: [] as MessagePart[],
                 content: '',
+                metadata: { agentName: prev.currentAgent },
               };
 
               // 复制 parts 数组以进行修改
@@ -180,6 +184,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                 timestamp: new Date().toISOString(),
                 parts: [] as MessagePart[],
                 content: '',
+                metadata: { agentName: prev.currentAgent },
               };
 
               // 添加工具调用 part
@@ -192,11 +197,19 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                 arguments: payload.arguments,
               };
 
+              // 如果是 task 工具，切换到子 agent
+              const newAgent =
+                payload.toolName === 'task' && payload.arguments?.subagent_type
+                  ? (payload.arguments.subagent_type as string)
+                  : prev.currentAgent;
+
               return {
                 ...prev,
+                currentAgent: newAgent,
                 streamingMessage: {
                   ...streaming,
                   parts: [...streaming.parts, toolPart],
+                  metadata: { ...streaming.metadata, agentName: newAgent },
                 },
               };
             });
@@ -222,11 +235,20 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                 return part;
               });
 
+              // 查找完成的工具是否为 task，如果是则恢复主 agent
+              const completedTool = prev.streamingMessage.parts.find(
+                (part) => part.type === 'tool' && part.id === payload.id
+              );
+              const isTaskTool = completedTool?.type === 'tool' && completedTool.toolName === 'task';
+              const newAgent = isTaskTool ? prev.agentMode : prev.currentAgent;
+
               return {
                 ...prev,
+                currentAgent: newAgent,
                 streamingMessage: {
                   ...prev.streamingMessage,
                   parts,
+                  metadata: { ...prev.streamingMessage.metadata, agentName: newAgent },
                 },
               };
             });
@@ -238,6 +260,8 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
               // 使用流式消息或创建新消息
               const streaming = prev.streamingMessage;
               const content = message.payload?.content || streaming?.content || '';
+              // 从服务器 payload 获取 agentName，或使用当前 agentMode
+              const agentName = message.payload?.agentName || prev.agentMode;
 
               const newMessage: Message = streaming
                 ? {
@@ -245,6 +269,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                     id: message.payload?.id || streaming.id,
                     timestamp: message.payload?.timestamp || streaming.timestamp,
                     content,
+                    metadata: { ...streaming.metadata, agentName },
                   }
                 : {
                     id: message.payload?.id || `assistant-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`,
@@ -252,6 +277,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                     timestamp: message.payload?.timestamp || new Date().toISOString(),
                     parts: [{ type: 'text', id: `text-${Date.now()}`, text: content }],
                     content,
+                    metadata: { agentName },
                   };
 
               return {
@@ -259,6 +285,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
                 messages: [...prev.messages, newMessage],
                 streamingMessage: null,
                 isLoading: false,
+                currentAgent: prev.agentMode, // 恢复为主 agent
               };
             });
             break;
@@ -448,6 +475,7 @@ export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdate
       permissionRequest: null,
       agentMode: 'build',
       autoApprove: false,
+      currentAgent: 'build',
     });
     reconnectAttemptsRef.current = 0;
 
diff --git a/packages/ui/src/utils/agent.ts b/packages/ui/src/utils/agent.ts
new file mode 100644
index 0000000..f537ae4
--- /dev/null
+++ b/packages/ui/src/utils/agent.ts
@@ -0,0 +1,26 @@
+/**
+ * Agent 工具函数
+ */
+
+/**
+ * Agent 显示名称映射
+ */
+export const AGENT_DISPLAY_NAMES: Record<string, string> = {
+  build: 'Build Agent',
+  plan: 'Plan Agent',
+  general: 'General Agent',
+  explore: 'Explore Agent',
+  'code-reviewer': 'Code Reviewer',
+  vision: 'Vision Agent',
+  summary: 'Summary Agent',
+};
+
+/**
+ * 获取 Agent 显示名称
+ * @param agentName Agent 名称（如 build、plan、explore 等）
+ * @returns 显示名称
+ */
+export function getAgentDisplayName(agentName?: string): string {
+  if (!agentName) return 'AI Assistant';
+  return AGENT_DISPLAY_NAMES[agentName] || agentName;
+}
diff --git a/packages/web/src/pages/Chat.tsx b/packages/web/src/pages/Chat.tsx
index 7bd8346..3e1621d 100644
--- a/packages/web/src/pages/Chat.tsx
+++ b/packages/web/src/pages/Chat.tsx
@@ -62,6 +62,7 @@ export function ChatPage({
     autoApprove,
     setAgentMode,
     setAutoApprove,
+    currentAgent,
   } = useChat({
     sessionId,
     onError: (error) => {
@@ -297,7 +298,7 @@ export function ChatPage({
             <ChatMessage message={streamingMessage} isStreaming />
           )}
 
-          {isLoading && !streamingMessage && <TypingIndicator />}
+          {isLoading && !streamingMessage && <TypingIndicator agentName={currentAgent} />}
 
           <div ref={messagesEndRef} />
         </div>