diff --git a/asserts/ARCHITECTURE.md b/asserts/ARCHITECTURE.md
index eeffd90..f5f2579 100644
--- a/asserts/ARCHITECTURE.md
+++ b/asserts/ARCHITECTURE.md
@@ -216,6 +216,82 @@ classDiagram
 | `get_weather` | 天气查询 | 支持城市名查询 |
 | `process_data` | 数据处理 | JSON 转换、格式化等 |
 
+#### 工具开发规范
+
+所有工具必须遵循统一的开发规范，确保错误处理和返回格式一致。
+
+**核心原则：装饰器自动处理一切，工具函数只写业务逻辑**
+
+```python
+from luxx.tools.factory import tool
+
+@tool(
+    name="my_tool",
+    description="工具描述",
+    parameters={...},
+    required_params=["arg1"],  # 自动验证
+    category="my_category"
+)
+def my_tool(arguments: dict):
+    # 业务逻辑 - 只管返回数据
+    data = fetch_data(arguments["arg1"])
+    return {"items": data, "count": len(data)}
+    
+    # 或者直接抛出异常（装饰器自动捕获并转换）
+    if invalid:
+        raise ValueError("Invalid input")
+```
+
+**装饰器自动处理：**
+1. 必需参数验证（`required_params`）
+2. 所有异常捕获和转换
+3. 结果格式统一包装
+
+**返回格式转换**
+
+| 工具函数返回/抛出 | 装饰器转换为 |
+|-------------------|-------------|
+| `return {"result": "ok"}` | `{"success": true, "data": {...}, "error": null}` |
+| `raise ValueError("msg")` | `{"success": false, "data": null, "error": "ValueError: msg"}` |
+| `raise Exception()` | `{"success": false, "data": null, "error": "..."}` |
+
+**工具调用流程**
+
+```
+LLM 请求
+    ↓
+ToolRegistry.execute(name, args)
+    ↓
+@tool 装饰器
+    ├─ 验证 required_params
+    ├─ 执行工具函数 (try-except 包裹)
+    ├─ 捕获异常 → 转换为 error
+    ├─ 包装返回格式
+    └─ 返回 ToolResult
+    ↓
+前端 ProcessBlock 显示
+```
+
+| 工具函数返回 | 装饰器转换为 |
+|-------------|-------------|
+| `{"result": "ok"}` | `{"success": true, "data": {...}, "error": null}` |
+| `{"error": "msg"}` | `{"success": false, "data": null, "error": "msg"}` |
+| `raise Exception()` | `{"success": false, "data": null, "error": "..."}` |
+
+**工具调用流程**
+
+```
+LLM 请求 → ToolRegistry.execute() → @tool 装饰器包装
+    ↓
+工具函数执行
+    ↓
+返回 ToolResult 或 dict
+    ↓
+自动转换为标准格式 {"success": bool, "data": any, "error": str}
+    ↓
+前端 ProcessBlock 显示结果
+```
+
 ### 6. 服务层
 
 #### ChatService (`services/chat.py`)
diff --git a/config.yaml b/config.yaml
index b83a005..27d6136 100644
--- a/config.yaml
+++ b/config.yaml
@@ -1,7 +1,7 @@
 # 配置文件
 app:
   secret_key: ${APP_SECRET_KEY}
-  debug: false
+  debug: true
   host: 0.0.0.0
   port: 8000
 
diff --git a/dashboard/src/components/ProcessBlock.vue b/dashboard/src/components/ProcessBlock.vue
index 5303d6e..810a8ca 100644
--- a/dashboard/src/components/ProcessBlock.vue
+++ b/dashboard/src/components/ProcessBlock.vue
@@ -113,13 +113,20 @@ const allItems = computed(() => {
         if (match) {
           let resultContent = step.content || ''
           let displayContent = resultContent
+          let hasError = false
           
           // 尝试解析 JSON 并格式化显示
           try {
             const parsed = JSON.parse(resultContent)
+            // 检查标准 ToolResult 格式
             if (parsed.error) {
               displayContent = `错误: ${parsed.error}`
+              hasError = true
+            } else if (parsed.success !== undefined && parsed.data !== undefined) {
+              // 标准 ToolResult 格式: 只显示 data 部分
+              displayContent = JSON.stringify(parsed.data, null, 2)
             } else {
+              // 旧格式或其他 JSON
               displayContent = JSON.stringify(parsed, null, 2)
             }
           } catch (e) {
@@ -129,7 +136,7 @@ const allItems = computed(() => {
           match.resultSummary = displayContent.slice(0, 200)
           match.fullResult = displayContent
           match.displayResult = displayContent.length > 2048 ? displayContent.slice(0, 2048) + '...' : displayContent
-          match.isSuccess = step.success !== false
+          match.isSuccess = !hasError && step.success !== false
           match.loading = false
         } else {
           // 如果没有找到对应的 tool_call，创建一个占位符
diff --git a/dashboard/src/utils/api.js b/dashboard/src/utils/api.js
index 7046059..387f4af 100644
--- a/dashboard/src/utils/api.js
+++ b/dashboard/src/utils/api.js
@@ -71,9 +71,41 @@ export function createSSEStream(url, body, { onProcessStep, onDone, onError }) {
 
       while (true) {
         const { done, value } = await reader.read()
-        if (done) break
+        
+        // 处理数据
+        if (value) {
+          buffer += decoder.decode(value, { stream: true })
+        }
+        
+        // 流结束时，先处理 buffer 中的剩余数据，再 break
+        if (done) {
+          // 处理 buffer 中剩余的数据
+          const lines = buffer.split('\n')
+          buffer = ''
+          
+          let currentEvent = ''
+          for (const line of lines) {
+            if (line.startsWith('event: ')) {
+              currentEvent = line.slice(7).trim()
+            } else if (line.startsWith('data: ')) {
+              try {
+                const data = JSON.parse(line.slice(6))
+                if (currentEvent === 'process_step' && onProcessStep) {
+                  onProcessStep(data.step)
+                } else if (currentEvent === 'done' && onDone) {
+                  completed = true
+                  onDone(data)
+                } else if (currentEvent === 'error' && onError) {
+                  onError(data.content)
+                }
+              } catch (e) {
+                // 忽略解析错误
+              }
+            }
+          }
+          break
+        }
 
-        buffer += decoder.decode(value, { stream: true })
         const lines = buffer.split('\n')
         buffer = lines.pop() || ''
 
@@ -82,19 +114,24 @@ export function createSSEStream(url, body, { onProcessStep, onDone, onError }) {
           if (line.startsWith('event: ')) {
             currentEvent = line.slice(7).trim()
           } else if (line.startsWith('data: ')) {
-            const data = JSON.parse(line.slice(6))
-            if (currentEvent === 'process_step' && onProcessStep) {
-              onProcessStep(data.step)
-            } else if (currentEvent === 'done' && onDone) {
-              completed = true
-              onDone(data)
-            } else if (currentEvent === 'error' && onError) {
-              onError(data.content)
+            try {
+              const data = JSON.parse(line.slice(6))
+              if (currentEvent === 'process_step' && onProcessStep) {
+                onProcessStep(data.step)
+              } else if (currentEvent === 'done' && onDone) {
+                completed = true
+                onDone(data)
+              } else if (currentEvent === 'error' && onError) {
+                onError(data.content)
+              }
+            } catch (e) {
+              // 忽略解析错误
             }
           }
         }
       }
 
+      // 流结束但没有收到 done 事件，才报错
       if (!completed && onError) {
         onError('stream ended unexpectedly')
       }
@@ -139,7 +176,8 @@ export const messagesAPI = {
     return createSSEStream('/messages/stream', {
       conversation_id: data.conversation_id,
       content: data.content,
-      thinking_enabled: data.thinking_enabled || false
+      thinking_enabled: data.thinking_enabled || false,
+      enabled_tools: data.enabled_tools || []
     }, callbacks)
   },
   
diff --git a/dashboard/src/views/ConversationDetailView.vue b/dashboard/src/views/ConversationDetailView.vue
index e962a9a..e012994 100644
--- a/dashboard/src/views/ConversationDetailView.vue
+++ b/dashboard/src/views/ConversationDetailView.vue
@@ -165,18 +165,8 @@ const loadEnabledTools = async () => {
   try {
     const res = await toolsAPI.list()
     if (res.success) {
-      const data = res.data?.categorized || {}
-      const enabled = []
-      Object.values(data).forEach(arr => {
-        if (Array.isArray(arr)) {
-          arr.forEach(t => {
-            if (t.enabled !== false) {
-              enabled.push(t.function?.name || t.name)
-            }
-          })
-        }
-      })
-      enabledTools.value = enabled
+      const tools = res.data?.tools || []
+      enabledTools.value = tools.map(t => t.function?.name || t.name)
     }
   } catch (e) {
     console.error('Failed to load tools:', e)
@@ -317,6 +307,15 @@ const formatTime = (time) => {
   return new Date(time).toLocaleTimeString('zh-CN', { hour: '2-digit', minute: '2-digit' })
 }
 
+// 监听对话 ID 变化，重新加载消息
+watch(() => route.params.id, (newId) => {
+  if (newId) {
+    conversationId.value = newId
+    loadMessages()
+    loadEnabledTools()
+  }
+})
+
 onMounted(() => {
   loadMessages()
   loadEnabledTools()
diff --git a/dashboard/src/views/ConversationsView.vue b/dashboard/src/views/ConversationsView.vue
index f7e9325..aa0b89a 100644
--- a/dashboard/src/views/ConversationsView.vue
+++ b/dashboard/src/views/ConversationsView.vue
@@ -139,7 +139,7 @@
 <script setup>
 import { ref, computed, onMounted, watch, nextTick } from 'vue'
 import { useRouter } from 'vue-router'
-import { conversationsAPI, providersAPI, messagesAPI } from '../utils/api.js'
+import { conversationsAPI, providersAPI, messagesAPI, toolsAPI } from '../utils/api.js'
 import { renderMarkdown } from '../utils/markdown.js'
 import ProcessBlock from '../components/ProcessBlock.vue'
 
@@ -158,9 +158,23 @@ const selectedId = ref(null)
 const selectedConv = ref(null)
 const convMessages = ref([])
 const loadingMessages = ref(false)
+const enabledTools = ref([])  // 启用的工具名称列表
 
 const totalPages = computed(() => Math.ceil(total.value / pageSize))
 
+// 加载启用的工具列表
+const loadEnabledTools = async () => {
+  try {
+    const res = await toolsAPI.list()
+    if (res.success) {
+      const tools = res.data?.tools || []
+      enabledTools.value = tools.map(t => t.function?.name || t.name)
+    }
+  } catch (e) {
+    console.error('Failed to load tools:', e)
+  }
+}
+
 const onProviderChange = () => {
   const p = providers.value.find(p => p.id === form.value.provider_id)
   if (p) form.value.model = p.default_model || ''
@@ -267,7 +281,8 @@ const sendMessage = async () => {
     await new Promise((resolve, reject) => {
       messagesAPI.sendStream({
         conversation_id: selectedConv.value.id,
-        content: content
+        content: content,
+        enabled_tools: enabledTools.value  // 传递启用的工具名称列表
       }, {
         onProcessStep: (step) => {
           if (!streamingMessage.value) return
@@ -356,7 +371,10 @@ const formatDate = (dateStr) => {
   return new Date(dateStr).toLocaleDateString('zh-CN', { month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' })
 }
 
-onMounted(fetchData)
+onMounted(() => {
+  fetchData()
+  loadEnabledTools()
+})
 </script>
 
 <style scoped>
diff --git a/luxx/__init__.py b/luxx/__init__.py
index 496d937..b09caac 100644
--- a/luxx/__init__.py
+++ b/luxx/__init__.py
@@ -35,6 +35,7 @@ async def lifespan(app: FastAPI):
     finally:
         db.close()
     
+    # Import and register tools
     from luxx.tools.builtin import crawler, code, data
     yield
 
diff --git a/luxx/routes/messages.py b/luxx/routes/messages.py
index 44ed900..abd6e3e 100644
--- a/luxx/routes/messages.py
+++ b/luxx/routes/messages.py
@@ -22,6 +22,7 @@ class MessageCreate(BaseModel):
     conversation_id: str
     content: str
     thinking_enabled: bool = False
+    enabled_tools: List[str] = []  # 启用的工具名称列表
 
 
 class MessageResponse(BaseModel):
@@ -142,7 +143,8 @@ async def stream_message(
         async for sse_str in chat_service.stream_response(
             conversation=conversation,
             user_message=data.content,
-            thinking_enabled=data.thinking_enabled
+            thinking_enabled=data.thinking_enabled,
+            enabled_tools=data.enabled_tools
         ):
             # Chat service returns raw SSE strings (including done event)
             yield sse_str
diff --git a/luxx/routes/tools.py b/luxx/routes/tools.py
index 0456fc1..7f8e27f 100644
--- a/luxx/routes/tools.py
+++ b/luxx/routes/tools.py
@@ -19,17 +19,24 @@ def list_tools(
     current_user: User = Depends(get_current_user)
 ):
     """Get available tools list"""
+    # Get tool definitions directly from registry to access category
+    from luxx.tools.core import ToolDefinition
+    
     if category:
-        tools = registry.list_by_category(category)
+        all_tools = [t for t in registry._tools.values() if t.category == category]
+        tools = [t.to_openai_format() for t in all_tools]
+        categorized_tools = [t for t in registry._tools.values() if t.category == category]
     else:
+        all_tools = list(registry._tools.values())
         tools = registry.list_all()
+        categorized_tools = all_tools
     
     categorized = {}
-    for tool in tools:
-        cat = tool.get("category", "other")
+    for tool in categorized_tools:
+        cat = tool.category
         if cat not in categorized:
             categorized[cat] = []
-        categorized[cat].append(tool)
+        categorized[cat].append(tool.to_openai_format())
     
     return success_response(data={
         "tools": tools,
diff --git a/luxx/services/chat.py b/luxx/services/chat.py
index cf304d2..c53ab9b 100644
--- a/luxx/services/chat.py
+++ b/luxx/services/chat.py
@@ -97,7 +97,8 @@ class ChatService:
         self,
         conversation: Conversation,
         user_message: str,
-        thinking_enabled: bool = False
+        thinking_enabled: bool = False,
+        enabled_tools: list = None
     ) -> AsyncGenerator[Dict[str, str], None]:
         """
         Streaming response generator
@@ -112,8 +113,11 @@ class ChatService:
                 "content": json.dumps({"text": user_message, "attachments": []})
             })
             
-            # Get all available tools
-            tools = registry.list_all()
+            # Get tools based on enabled_tools filter
+            if enabled_tools:
+                tools = [t for t in registry.list_all() if t.get("function", {}).get("name") in enabled_tools]
+            else:
+                tools = []
             
             llm, provider_max_tokens = get_llm_client(conversation)
             model = conversation.model or llm.default_model or "gpt-4"
@@ -133,8 +137,6 @@ class ChatService:
             text_step_idx = None
             
             for iteration in range(MAX_ITERATIONS):
-                print(f"[CHAT] Starting iteration {iteration + 1}, messages: {len(messages)}")
-                
                 # Stream from LLM
                 full_content = ""
                 full_thinking = ""
@@ -193,19 +195,25 @@ class ChatService:
                     # Get delta
                     choices = chunk.get("choices", [])
                     if not choices:
-                        # Check if there's any content in the response
+                        # Check if there's any content in the response (for non-standard LLM responses)
                         if chunk.get("content") or chunk.get("message"):
                             content = chunk.get("content") or chunk.get("message", {}).get("content", "")
                             if content:
+                                # BUG FIX: Update full_content so it gets saved to database
+                                prev_content_len = len(full_content)
+                                full_content += content
+                                if prev_content_len == 0:  # New text stream started
+                                    text_step_idx = step_index
+                                    text_step_id = f"step-{step_index}"
+                                    step_index += 1
                                 yield _sse_event("process_step", {
                                     "step": {
-                                        "id": f"step-{step_index}",
-                                        "index": step_index,
+                                        "id": text_step_id if prev_content_len == 0 else f"step-{step_index - 1}",
+                                        "index": text_step_idx if prev_content_len == 0 else step_index - 1,
                                         "type": "text",
-                                        "content": content
+                                        "content": full_content  # Always send accumulated content
                                     }
                                 })
-                                step_index += 1
                         continue
                     
                     delta = choices[0].get("delta", {})
@@ -313,13 +321,25 @@ class ChatService:
                         result_step_idx = step_index
                         result_step_id = f"step-{step_index}"
                         step_index += 1
+                        
+                        # 解析 content 中的 success 状态
+                        content = tr.get("content", "")
+                        success = True
+                        try:
+                            content_obj = json.loads(content)
+                            if isinstance(content_obj, dict):
+                                success = content_obj.get("success", True)
+                        except:
+                            pass
+                        
                         result_step = {
                             "id": result_step_id,
                             "index": result_step_idx,
                             "type": "tool_result",
                             "id_ref": tool_call_step_id,  # Reference to the tool_call step
                             "name": tr.get("name", ""),
-                            "content": tr.get("content", "")
+                            "content": content,
+                            "success": success
                         }
                         all_steps.append(result_step)
                         yield _sse_event("process_step", {"step": result_step})
@@ -357,11 +377,20 @@ class ChatService:
                 })
                 return
             
-            # Max iterations exceeded
+            # Max iterations exceeded - save message before error
+            if full_content or all_tool_calls:
+                msg_id = str(uuid.uuid4())
+                self._save_message(
+                    conversation.id,
+                    msg_id,
+                    full_content,
+                    all_tool_calls,
+                    all_tool_results,
+                    all_steps
+                )
             yield _sse_event("error", {"content": "Exceeded maximum tool call iterations"})
             
         except Exception as e:
-            print(f"[CHAT] Exception: {type(e).__name__}: {str(e)}")
             yield _sse_event("error", {"content": str(e)})
     
     def _save_message(
@@ -396,8 +425,8 @@ class ChatService:
             db.add(msg)
             db.commit()
         except Exception as e:
-            print(f"[CHAT] Failed to save message: {e}")
             db.rollback()
+            raise
         finally:
             db.close()
 
diff --git a/luxx/tools/builtin/code.py b/luxx/tools/builtin/code.py
index d883581..fac0077 100644
--- a/luxx/tools/builtin/code.py
+++ b/luxx/tools/builtin/code.py
@@ -1,6 +1,6 @@
-"""Code execution tools"""
-import json
-import traceback
+"""Code execution tools - exception handling in decorator"""
+import io
+from contextlib import redirect_stdout
 from typing import Dict, Any
 
 from luxx.tools.factory import tool
@@ -24,53 +24,45 @@ from luxx.tools.factory import tool
         },
         "required": ["code"]
     },
+    required_params=["code"],
     category="code"
 )
-def python_execute(arguments: Dict[str, Any]) -> Dict[str, Any]:
+def python_execute(arguments: Dict[str, Any]):
     """
     Execute Python code
     
     Note: This is a simplified executor, production environments should use safer isolated environments
     such as: Docker containers, Pyodide, etc.
+    
+    Returns:
+        {"output": str, "variables": dict}
     """
     code = arguments.get("code", "")
-    timeout = arguments.get("timeout", 30)
-    
-    if not code:
-        return {"error": "Code is required"}
     
     # Create execution environment
     namespace = {
         "__builtins__": __builtins__
     }
     
-    try:
-        # Compile and execute code
-        compiled = compile(code, "<string>", "exec")
-        
-        # Capture output
-        import io
-        from contextlib import redirect_stdout
-        
-        output = io.StringIO()
-        
-        with redirect_stdout(output):
-            exec(compiled, namespace)
-        
-        result = output.getvalue()
-        
-        # Try to extract variables
-        result_vars = {k: v for k, v in namespace.items() 
-                      if not k.startswith("_") and k != "__builtins__"}
-        
-        return {
-            "output": result,
-            "variables": {k: repr(v) for k, v in result_vars.items()}
-        }
-    except SyntaxError as e:
-        return {"error": f"Syntax error: {e}"}
-    except Exception as e:
-        return {"error": f"Runtime error: {type(e).__name__}: {str(e)}"}
+    # Compile and execute code
+    compiled = compile(code, "<string>", "exec")
+    
+    # Capture output
+    output = io.StringIO()
+    
+    with redirect_stdout(output):
+        exec(compiled, namespace)
+    
+    result = output.getvalue()
+    
+    # Extract variables
+    result_vars = {k: v for k, v in namespace.items() 
+                  if not k.startswith("_") and k != "__builtins__"}
+    
+    return {
+        "output": result,
+        "variables": {k: repr(v) for k, v in result_vars.items()}
+    }
 
 
 @tool(
@@ -86,20 +78,20 @@ def python_execute(arguments: Dict[str, Any]) -> Dict[str, Any]:
         },
         "required": ["expression"]
     },
+    required_params=["expression"],
     category="code"
 )
-def python_eval(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """Evaluate Python expression"""
+def python_eval(arguments: Dict[str, Any]):
+    """
+    Evaluate Python expression
+    
+    Returns:
+        {"result": str, "type": str}
+    """
     expression = arguments.get("expression", "")
     
-    if not expression:
-        return {"error": "Expression is required"}
-    
-    try:
-        result = eval(expression)
-        return {
-            "result": repr(result),
-            "type": type(result).__name__
-        }
-    except Exception as e:
-        return {"error": f"Evaluation error: {str(e)}"}
+    result = eval(expression)
+    return {
+        "result": repr(result),
+        "type": type(result).__name__
+    }
diff --git a/luxx/tools/builtin/crawler.py b/luxx/tools/builtin/crawler.py
index bc12b7f..4eb548f 100644
--- a/luxx/tools/builtin/crawler.py
+++ b/luxx/tools/builtin/crawler.py
@@ -1,7 +1,10 @@
-"""Crawler tools"""
+"""Crawler tools - all exception handling in decorator"""
 from luxx.tools.factory import tool
 from luxx.tools.services import SearchService, FetchService
 
+# 服务实例（SearchService.search() 是静态方法风格，不需要实例化）
+_fetch_service = FetchService()
+
 
 @tool(name="web_search", description="Search the internet. Use when you need to find latest news or answer questions.", parameters={
     "type": "object",
@@ -10,42 +13,63 @@ from luxx.tools.services import SearchService, FetchService
         "max_results": {"type": "integer", "description": "Number of results, default 5", "default": 5}
     },
     "required": ["query"]
-}, category="crawler")
-def web_search(arguments: dict) -> dict:
-    results = SearchService().search(arguments["query"], arguments.get("max_results", 5))
-    return {"results": results or []}
+}, required_params=["query"], category="crawler")
+def web_search(arguments: dict):
+    """
+    Search the web using DuckDuckGo
+    
+    Returns:
+        {"query": str, "count": int, "results": list}
+    """
+    query = arguments["query"]
+    max_results = arguments.get("max_results", 5)
+    
+    results = SearchService().search(query, max_results)
+    return {
+        "query": query,
+        "count": len(results),
+        "results": results
+    }
 
 
 @tool(name="web_fetch", description="Fetch content from a webpage.", parameters={
     "type": "object",
     "properties": {
-        "url": {"type": "string", "description": "URL to fetch"},
-        "extract_type": {"type": "string", "enum": ["text", "links", "structured"], "default": "text"}
+        "url": {"type": "string", "description": "URL to fetch"}
     },
     "required": ["url"]
-}, category="crawler")
-def web_fetch(arguments: dict) -> dict:
-    if not arguments.get("url"):
-        return {"error": "URL is required"}
-    result = FetchService().fetch(arguments["url"], arguments.get("extract_type", "text"))
-    if "error" in result:
-        return {"error": result["error"]}
-    return result
+}, required_params=["url"], category="crawler")
+def web_fetch(arguments: dict):
+    """
+    Fetch webpage content
+    
+    Returns:
+        {"url": str, "title": str, "text": str}
+    """
+    url = arguments["url"]
+    
+    return _fetch_service.fetch(url)
 
 
 @tool(name="batch_fetch", description="Batch fetch multiple webpages.", parameters={
     "type": "object",
     "properties": {
-        "urls": {"type": "array", "items": {"type": "string"}, "description": "URLs to fetch"},
-        "extract_type": {"type": "string", "enum": ["text", "links", "structured"], "default": "text"}
+        "urls": {"type": "array", "items": {"type": "string"}, "description": "URLs to fetch"}
     },
     "required": ["urls"]
-}, category="crawler")
-def batch_fetch(arguments: dict) -> dict:
+}, required_params=["urls"], category="crawler")
+def batch_fetch(arguments: dict):
+    """
+    Batch fetch multiple webpages
+    
+    Returns:
+        {"count": int, "results": list}
+    """
     urls = arguments.get("urls", [])
-    if not urls:
-        return {"error": "URLs list is required"}
-    if len(urls) > 10:
-        return {"error": "Maximum 10 pages allowed"}
-    results = FetchService().fetch_batch(urls, arguments.get("extract_type", "text"))
-    return {"results": results, "total": len(results)}
+    
+    results = _fetch_service.fetch_batch(urls)
+    
+    return {
+        "count": len(results),
+        "results": results
+    }
diff --git a/luxx/tools/builtin/data.py b/luxx/tools/builtin/data.py
index 540ea4d..6d1ffe9 100644
--- a/luxx/tools/builtin/data.py
+++ b/luxx/tools/builtin/data.py
@@ -1,7 +1,8 @@
-"""Data processing tools"""
+"""Data processing tools - exception handling in decorator"""
 import re
 import json
 import base64
+import hashlib
 from typing import Dict, Any
 from urllib.parse import quote, unquote
 
@@ -21,40 +22,39 @@ from luxx.tools.factory import tool
         },
         "required": ["expression"]
     },
+    required_params=["expression"],
     category="data"
 )
-def calculate(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """Execute mathematical calculation"""
+def calculate(arguments: Dict[str, Any]):
+    """
+    Execute mathematical calculation
+    
+    Returns:
+        {"result": float, "expression": str}
+    """
     expression = arguments.get("expression", "")
     
-    if not expression:
-        return {"error": "Expression is required"}
+    # Safe replacement for math functions
+    safe_dict = {
+        "abs": abs,
+        "round": round,
+        "min": min,
+        "max": max,
+        "pow": pow,
+        "sqrt": lambda x: x ** 0.5,
+        "sin": lambda x: __import__('math').sin(x),
+        "cos": lambda x: __import__('math').cos(x),
+        "tan": lambda x: __import__('math').tan(x),
+        "log": lambda x: __import__('math').log(x),
+        "pi": __import__('math').pi,
+        "e": __import__('math').e
+    }
     
-    try:
-        # Safe replacement for math functions
-        safe_dict = {
-            "abs": abs,
-            "round": round,
-            "min": min,
-            "max": max,
-            "pow": pow,
-            "sqrt": lambda x: x ** 0.5,
-            "sin": lambda x: __import__('math').sin(x),
-            "cos": lambda x: __import__('math').cos(x),
-            "tan": lambda x: __import__('math').tan(x),
-            "log": lambda x: __import__('math').log(x),
-            "pi": __import__('math').pi,
-            "e": __import__('math').e
-        }
-        
-        # Remove dangerous characters, only keep numbers and operators
-        safe_expr = re.sub(r"[^0-9+\-*/().%sqrtinsclogmaxminpowabsroundte, ]", "", expression)
-        
-        result = eval(safe_expr, {"__builtins__": {}, **safe_dict})
-        
-        return {"result": result}
-    except Exception as e:
-        return {"error": f"Calculation error: {str(e)}"}
+    # Remove dangerous characters, only keep numbers and operators
+    safe_expr = re.sub(r"[^0-9+\-*/().%sqrtinsclogmaxminpowabsroundte, ]", "", expression)
+    result = eval(safe_expr, {"__builtins__": {}, **safe_dict})
+    
+    return {"result": result, "expression": expression}
 
 
 @tool(
@@ -69,22 +69,25 @@ def calculate(arguments: Dict[str, Any]) -> Dict[str, Any]:
             },
             "operation": {
                 "type": "string",
-                "description": "Operation to perform: uppercase, lowercase, title, strip, reverse, word_count, char_count",
+                "description": "Operation to perform",
                 "enum": ["uppercase", "lowercase", "title", "strip", "reverse", "word_count", "char_count"]
             }
         },
         "required": ["text", "operation"]
     },
+    required_params=["text", "operation"],
     category="data"
 )
-def text_process(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """Text processing"""
+def text_process(arguments: Dict[str, Any]):
+    """
+    Text processing operations
+    
+    Returns:
+        {"operation": str, "result": str|int, "original_length": int}
+    """
     text = arguments.get("text", "")
     operation = arguments.get("operation", "")
     
-    if not text:
-        return {"error": "Text is required"}
-    
     operations = {
         "uppercase": text.upper(),
         "lowercase": text.lower(),
@@ -96,11 +99,14 @@ def text_process(arguments: Dict[str, Any]) -> Dict[str, Any]:
     }
     
     result = operations.get(operation)
-    
     if result is None:
-        return {"error": f"Unknown operation: {operation}"}
+        raise ValueError(f"Unknown operation: {operation}")
     
-    return {"result": result}
+    return {
+        "operation": operation,
+        "result": result,
+        "original_length": len(text)
+    }
 
 
 @tool(
@@ -121,31 +127,31 @@ def text_process(arguments: Dict[str, Any]) -> Dict[str, Any]:
         },
         "required": ["data", "operation"]
     },
+    required_params=["data", "operation"],
     category="data"
 )
-def json_process(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """JSON data processing"""
+def json_process(arguments: Dict[str, Any]):
+    """
+    JSON data processing
+    
+    Returns:
+        {"operation": str, "result": str}
+    """
     data = arguments.get("data", "")
     operation = arguments.get("operation", "")
     
-    if not data:
-        return {"error": "Data is required"}
+    parsed = json.loads(data)
     
-    try:
-        parsed = json.loads(data)
-        
-        if operation == "format":
-            result = json.dumps(parsed, indent=2, ensure_ascii=False)
-        elif operation == "minify":
-            result = json.dumps(parsed, ensure_ascii=False)
-        elif operation == "validate":
-            result = "Valid JSON"
-        else:
-            return {"error": f"Unknown operation: {operation}"}
-        
-        return {"result": result}
-    except json.JSONDecodeError as e:
-        return {"error": f"Invalid JSON: {str(e)}"}
+    if operation == "format":
+        result = json.dumps(parsed, indent=2, ensure_ascii=False)
+    elif operation == "minify":
+        result = json.dumps(parsed, ensure_ascii=False)
+    elif operation == "validate":
+        result = "Valid JSON"
+    else:
+        raise ValueError(f"Unknown operation: {operation}")
+    
+    return {"operation": operation, "result": result}
 
 
 @tool(
@@ -160,32 +166,35 @@ def json_process(arguments: Dict[str, Any]) -> Dict[str, Any]:
             },
             "algorithm": {
                 "type": "string",
-                "description": "Hash algorithm: md5, sha1, sha256, sha512",
+                "description": "Hash algorithm",
+                "enum": ["md5", "sha1", "sha256", "sha512"],
                 "default": "sha256"
             }
         },
         "required": ["text"]
     },
+    required_params=["text"],
     category="data"
 )
-def hash_text(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """Generate text hash"""
-    import hashlib
+def hash_text(arguments: Dict[str, Any]):
+    """
+    Generate text hash
     
+    Returns:
+        {"algorithm": str, "hash": str, "length": int}
+    """
     text = arguments.get("text", "")
     algorithm = arguments.get("algorithm", "sha256")
     
-    if not text:
-        return {"error": "Text is required"}
+    hash_obj = hashlib.new(algorithm)
+    hash_obj.update(text.encode('utf-8'))
+    hash_value = hash_obj.hexdigest()
     
-    try:
-        hash_obj = hashlib.new(algorithm)
-        hash_obj.update(text.encode('utf-8'))
-        hash_value = hash_obj.hexdigest()
-        
-        return {"hash": hash_value}
-    except Exception as e:
-        return {"error": f"Hash error: {str(e)}"}
+    return {
+        "algorithm": algorithm,
+        "hash": hash_value,
+        "length": len(hash_value)
+    }
 
 
 @tool(
@@ -200,33 +209,33 @@ def hash_text(arguments: Dict[str, Any]) -> Dict[str, Any]:
             },
             "operation": {
                 "type": "string",
-                "description": "Operation: encode, decode",
+                "description": "Operation",
                 "enum": ["encode", "decode"]
             }
         },
         "required": ["text", "operation"]
     },
+    required_params=["text", "operation"],
     category="data"
 )
-def url_encode_decode(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """URL encoding/decoding"""
+def url_encode_decode(arguments: Dict[str, Any]):
+    """
+    URL encoding/decoding
+    
+    Returns:
+        {"operation": str, "result": str}
+    """
     text = arguments.get("text", "")
     operation = arguments.get("operation", "")
     
-    if not text:
-        return {"error": "Text is required"}
+    if operation == "encode":
+        result = quote(text)
+    elif operation == "decode":
+        result = unquote(text)
+    else:
+        raise ValueError(f"Unknown operation: {operation}")
     
-    try:
-        if operation == "encode":
-            result = quote(text)
-        elif operation == "decode":
-            result = unquote(text)
-        else:
-            return {"error": f"Unknown operation: {operation}"}
-        
-        return {"result": result}
-    except Exception as e:
-        return {"error": f"URL error: {str(e)}"}
+    return {"operation": operation, "result": result}
 
 
 @tool(
@@ -241,30 +250,30 @@ def url_encode_decode(arguments: Dict[str, Any]) -> Dict[str, Any]:
             },
             "operation": {
                 "type": "string",
-                "description": "Operation: encode, decode",
+                "description": "Operation",
                 "enum": ["encode", "decode"]
             }
         },
         "required": ["text", "operation"]
     },
+    required_params=["text", "operation"],
     category="data"
 )
-def base64_encode_decode(arguments: Dict[str, Any]) -> Dict[str, Any]:
-    """Base64 encoding/decoding"""
+def base64_encode_decode(arguments: Dict[str, Any]):
+    """
+    Base64 encoding/decoding
+    
+    Returns:
+        {"operation": str, "result": str}
+    """
     text = arguments.get("text", "")
     operation = arguments.get("operation", "")
     
-    if not text:
-        return {"error": "Text is required"}
+    if operation == "encode":
+        result = base64.b64encode(text.encode()).decode()
+    elif operation == "decode":
+        result = base64.b64decode(text.encode()).decode()
+    else:
+        raise ValueError(f"Unknown operation: {operation}")
     
-    try:
-        if operation == "encode":
-            result = base64.b64encode(text.encode()).decode()
-        elif operation == "decode":
-            result = base64.b64decode(text.encode()).decode()
-        else:
-            return {"error": f"Unknown operation: {operation}"}
-        
-        return {"result": result}
-    except Exception as e:
-        return {"error": f"Base64 error: {str(e)}"}
+    return {"operation": operation, "result": result}
diff --git a/luxx/tools/factory.py b/luxx/tools/factory.py
index 15d7347..dd9bde0 100644
--- a/luxx/tools/factory.py
+++ b/luxx/tools/factory.py
@@ -1,16 +1,31 @@
-"""Tool decorator factory"""
-from typing import Callable, Any, Dict
-from luxx.tools.core import ToolDefinition, registry
+"""Tool decorator factory with unified result wrapping"""
+from typing import Callable, Any, Dict, Optional, List
+from luxx.tools.core import ToolDefinition, ToolResult, registry
+import traceback
+import logging
+
+logger = logging.getLogger(__name__)
 
 
 def tool(
     name: str,
     description: str,
     parameters: Dict[str, Any],
-    category: str = "general"
+    category: str = "general",
+    required_params: Optional[List[str]] = None
 ):
     """
-    Tool registration decorator
+    Tool registration decorator with UNIFED result wrapping
+    
+    The decorator automatically wraps all return values into ToolResult format.
+    Tool functions only need to return plain data - no need to use ToolResult manually.
+    
+    Args:
+        name: Tool name
+        description: Tool description
+        parameters: OpenAI format parameters schema
+        category: Tool category
+        required_params: List of required parameter names (auto-validated)
     
     Usage:
     ```python
@@ -23,21 +38,52 @@ def tool(
                 "arg1": {"type": "string"}
             },
             "required": ["arg1"]
-        }
+        },
+        required_params=["arg1"]  # Auto-validated
     )
-    def my_tool(arguments: dict) -> dict:
-        # Implementation...
-        return {"result": "success"}
+    def my_tool(arguments: dict):
+        # Just return plain data - decorator handles wrapping!
+        return {"result": "success", "count": 5}
     
-    # The tool will be automatically registered
+    # For errors, return a dict with "error" key:
+    def my_tool2(arguments: dict):
+        return {"error": "Something went wrong"}
+    
+    # Or raise an exception:
+    def my_tool3(arguments: dict):
+        raise ValueError("Invalid input")
     ```
+    
+    The decorator will convert:
+    - Plain dict → {"success": true, "data": dict, "error": null}
+    - {"error": "msg"} → {"success": false, "data": null, "error": "msg"}
+    - Exception → {"success": false, "data": null, "error": "..."}
     """
     def decorator(func: Callable) -> Callable:
+        def wrapped_handler(arguments: Dict[str, Any]) -> ToolResult:
+            try:
+                # 1. Validate required params
+                if required_params:
+                    for param in required_params:
+                        if param not in arguments or arguments[param] is None:
+                            return ToolResult.fail(f"Missing required parameter: {param}")
+                
+                # 2. Execute handler
+                result = func(arguments)
+                
+                # 3. Auto-wrap result
+                return _auto_wrap(result)
+                
+            except Exception as e:
+                logger.error(f"[{name}] Unexpected error: {type(e).__name__}: {str(e)}")
+                logger.debug(traceback.format_exc())
+                return ToolResult.fail(f"Execution failed: {type(e).__name__}: {str(e)}")
+        
         tool_def = ToolDefinition(
             name=name,
             description=description,
             parameters=parameters,
-            handler=func,
+            handler=wrapped_handler,
             category=category
         )
         registry.register(tool_def)
@@ -45,13 +91,44 @@ def tool(
     return decorator
 
 
+def _auto_wrap(result: Any) -> ToolResult:
+    """
+    Auto-wrap any return value into ToolResult format
+    
+    Rules:
+    - ToolResult → use directly
+    - dict with "error" key → ToolResult.fail()
+    - dict without "error" → ToolResult.ok()
+    - other values → ToolResult.ok()
+    """
+    # Already a ToolResult
+    if isinstance(result, ToolResult):
+        return result
+    
+    # Dict with error
+    if isinstance(result, dict) and "error" in result:
+        return ToolResult.fail(str(result["error"]))
+    
+    # Plain dict or other value
+    return ToolResult.ok(result)
+
+
 def tool_function(
     name: str = None,
     description: str = None,
     parameters: Dict[str, Any] = None,
-    category: str = "general"
+    category: str = "general",
+    required_params: Optional[List[str]] = None
 ):
     """
     Alias for tool decorator, providing a more semantic naming
+    
+    All parameters are the same as tool()
     """
-    return tool(name=name, description=description, parameters=parameters, category=category)
+    return tool(
+        name=name, 
+        description=description, 
+        parameters=parameters, 
+        category=category,
+        required_params=required_params
+    )
diff --git a/luxx/tools/services.py b/luxx/tools/services.py
index 42b49f2..3877896 100644
--- a/luxx/tools/services.py
+++ b/luxx/tools/services.py
@@ -13,15 +13,13 @@ class SearchService:
 
     def search(self, query: str, max_results: int = 5) -> List[dict]:
         results = []
-        try:
-            for result in DDGS().text(query, max_results=max_results):
+        with DDGS() as client:
+            for result in client.text(query, max_results=max_results):
                 results.append({
                     "title": result.get("title", ""),
                     "url": result.get("href", ""),
                     "snippet": result.get("body", "")
                 })
-        except Exception:
-            pass
         return results
 
 
@@ -35,32 +33,27 @@ class FetchService:
         if not url.startswith(("http://", "https://")):
             url = "https://" + url
 
-        try:
-            headers = {
-                "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
+        headers = {
+            "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
+        }
+        with httpx.Client(timeout=self.timeout, follow_redirects=True) as client:
+            response = client.get(url, headers=headers)
+            response.raise_for_status()
+            
+            soup = BeautifulSoup(response.text, "html.parser")
+            
+            # Remove script and style elements
+            for script in soup(["script", "style"]):
+                script.decompose()
+            
+            title = soup.title.string if soup.title else ""
+            text = soup.get_text(separator="\n", strip=True)
+            
+            return {
+                "url": url,
+                "title": title[:500] if title else "",
+                "text": text[:15000]
             }
-            with httpx.Client(timeout=self.timeout, follow_redirects=True) as client:
-                response = client.get(url, headers=headers)
-                response.raise_for_status()
-                
-                soup = BeautifulSoup(response.text, "html.parser")
-                
-                # Remove script and style elements
-                for script in soup(["script", "style"]):
-                    script.decompose()
-                
-                title = soup.title.string if soup.title else ""
-                text = soup.get_text(separator="\n", strip=True)
-                
-                return {
-                    "url": url,
-                    "title": title[:500] if title else "",
-                    "text": text[:15000]
-                }
-        except Exception as e:
-            return {"error": str(e)}
-
-        return {"url": url, "title": "", "text": ""}
 
     def fetch_batch(self, urls: List[str], extract_type: str = "text", max_concurrent: int = 5) -> List[dict]:
         if len(urls) <= 1:
@@ -72,9 +65,6 @@ class FetchService:
         with ThreadPoolExecutor(max_workers=max_concurrent) as pool:
             futures = {pool.submit(self.fetch, url, extract_type): i for i, url in enumerate(urls)}
             for future in as_completed(futures):
-                try:
-                    results[futures[future]] = future.result()
-                except Exception as e:
-                    results[futures[future]] = {"error": str(e)}
+                results[futures[future]] = future.result()
 
         return results