refactor(sse): simplify error handling and remove __debug__ security issue

- Remove __debug__ conditional that exposed tracebacks in production
- Simplify error response structure to {"error": str(e)}
- Remove redundant exception handling in init_agent()
- Remove unnecessary traceback logging
- Reduce code from ~30 lines to ~10 lines

Fixes security vulnerability where __debug__ is always True
unless Python runs with -O flag, causing full tracebacks
to be sent to clients in production.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

agent/deep_assistant.py

@@ -102,11 +102,8 @@ async def get_tools_from_mcp(mcp):
         logger.info(f"get_tools_from_mcp: loaded {len(mcp_tools)} tools, elapsed: {time.time() - start_time:.3f}s")
         return mcp_tools
     except Exception as e:
-        import traceback
-        error_details = traceback.format_exc()
         # 发生异常时返回空列表，避免上层调用报错
-        logger.error(f"get_tools_from_mcp: error {str(e)}, elapsed: {time.time() - start_time:.3f}s")
+        logger.error(f"get_tools_from_mcp: error {e}, elapsed: {time.time() - start_time:.3f}s")
-        logger.error(f"Full traceback: {error_details}")
         return []
 
 async def init_agent(config: AgentConfig):
@@ -142,12 +139,8 @@ async def init_agent(config: AgentConfig):
     config.mcp_settings = system_prompt
 
     # 获取 mcp_tools（缓存逻辑已内置到 get_tools_from_mcp 中）
-    try:
+    mcp_tools = await get_tools_from_mcp(mcp_settings)
-        mcp_tools = await get_tools_from_mcp(mcp_settings)
+    logger.info(f"Loaded {len(mcp_tools)} MCP tools")
-        logger.info(f"Successfully loaded {len(mcp_tools)} MCP tools")
-    except Exception as e:
-        logger.error(f"Failed to load MCP tools: {str(e)}, using empty tool list")
-        mcp_tools = []
 
     # 检测或使用指定的提供商
     model_provider, base_url = detect_provider(config.model_name, config.model_server)

routes/chat.py

@@ -114,21 +114,9 @@ async def enhanced_generate_stream_response(
                 await output_queue.put(("agent_done", None))
 
             except Exception as e:
-                import traceback
+                logger.error(f"Error in agent task: {e}")
-                error_details = traceback.format_exc()
-                logger.error(f"Error in agent task: {str(e)}")
-                logger.error(f"Full traceback: {error_details}")
-
                 # 发送错误信息给客户端
-                error_data = {
+                await output_queue.put(("agent", f'data: {{"error": "{str(e)}"}}\n\n'))
-                    "error": {
-                        "message": f"Agent execution failed: {str(e)}",
-                        "type": "agent_error",
-                        "details": error_details if __debug__ else str(e)
-                    }
-                }
-                error_chunk = create_stream_chunk(f"chatcmpl-error", config.model_name, json.dumps(error_data, ensure_ascii=False))
-                await output_queue.put(("agent", f"data: {json.dumps(error_chunk, ensure_ascii=False)}\n\n"))
                 # 发送完成信号，确保输出控制器能正常结束
                 await output_queue.put(("agent_done", None))
 
@@ -189,18 +177,8 @@ async def enhanced_generate_stream_response(
         logger.info(f"Enhanced stream response completed")
 
     except Exception as e:
-        import traceback
+        logger.error(f"Error in enhanced_generate_stream_response: {e}")
-        error_details = traceback.format_exc()
+        yield f'data: {{"error": "{str(e)}"}}\n\n'
-        logger.error(f"Error in enhanced_generate_stream_response: {str(e)}")
-        logger.error(f"Full traceback: {error_details}")
-
-        error_data = {
-            "error": {
-                "message": f"Stream error: {str(e)}",
-                "type": "internal_error"
-            }
-        }
-        yield f"data: {json.dumps(error_data, ensure_ascii=False)}\n\n"
         yield "data: [DONE]\n\n"