diff --git a/server/routes/agent-chat.js b/server/routes/agent-chat.js
index 5e44023..9b24480 100644
--- a/server/routes/agent-chat.js
+++ b/server/routes/agent-chat.js
@@ -493,28 +493,10 @@ function saveMeta(agentId, convId, meta) {
 function loadHistory(agentId, convId) {
   try {
     const historyPath = path.join(getAgentDir(agentId), 'conversations', convId, 'history.json');
-    const logPath = path.join(getAgentDir(agentId), 'conversations', convId, 'messages.log');
-    
-    let history = [];
     if (fs.existsSync(historyPath)) {
-      history = JSON.parse(fs.readFileSync(historyPath, 'utf-8'));
-    }
-    
-    // 如果 messages.log 存在且比 history.json 更丰富, 从 log 里解析完整消息
-    if (fs.existsSync(logPath)) {
-      const logContent = fs.readFileSync(logPath, 'utf-8');
-      const parsed = parseMessagesLog(logContent);
-      // 只有当 log 解析出的消息更丰富时才使用 (例如包含更多内容)
-      if (parsed.length > 0) {
-        const historyTotalLen = history.reduce((sum, m) => sum + (m.content || '').length, 0);
-        const logTotalLen = parsed.reduce((sum, m) => sum + (m.content || '').length, 0);
-        if (logTotalLen > historyTotalLen * 1.5) {
-          return parsed;
-        }
-      }
+      return JSON.parse(fs.readFileSync(historyPath, 'utf-8'));
     }
-    
-    return history;
+    return [];
   } catch { return []; }
 }
 
@@ -552,10 +534,43 @@ function appendHistory(agentId, convId, msg) {
   fs.writeFileSync(path.join(dir, 'history.json'), JSON.stringify(history, null, 2));
 }
 
-/** 写日志（流式或单次） */
+/** 写日志（流式，带缓冲） */
+const _logBuffers = new Map();
+const LOG_BUFFER_SIZE = 4096; // 4KB
+const LOG_FLUSH_INTERVAL = 1000; // 1s
+
 function logMessageChunk(agentId, convId, content) {
-  const dir = getConvDir(agentId, convId);
-  fs.appendFileSync(path.join(dir, 'messages.log'), content, 'utf-8');
+  const key = `${agentId}::${convId}`;
+  if (!_logBuffers.has(key)) {
+    _logBuffers.set(key, { buf: '', timer: null, agentId, convId });
+  }
+  const entry = _logBuffers.get(key);
+  entry.buf += content;
+  if (entry.buf.length >= LOG_BUFFER_SIZE) {
+    _flushLogBuffer(key);
+  } else if (!entry.timer) {
+    entry.timer = setTimeout(() => _flushLogBuffer(key), LOG_FLUSH_INTERVAL);
+  }
+}
+
+function _flushLogBuffer(key) {
+  const entry = _logBuffers.get(key);
+  if (!entry || !entry.buf) return;
+  try {
+    const dir = getConvDir(entry.agentId, entry.convId);
+    fs.appendFileSync(path.join(dir, 'messages.log'), entry.buf, 'utf-8');
+  } catch (err) {
+    console.error(`[LogBuffer] ⚠️ flush 失败: ${key}`, err.message);
+  }
+  entry.buf = '';
+  if (entry.timer) { clearTimeout(entry.timer); entry.timer = null; }
+}
+
+/** 强制刷出指定对话的日志缓冲 */
+function flushLogBufferForConv(agentId, convId) {
+  const key = `${agentId}::${convId}`;
+  _flushLogBuffer(key);
+  _logBuffers.delete(key);
 }
 
 /** 传统单次写日志 (为了兼容) */
@@ -818,8 +833,18 @@ router.get('/quota', (req, res) => {
   }
 });
 
+// ── Agent List 缓存 (5秒 TTL，避免每次请求全量扫描磁盘) ──
+let _agentListCache = null;
+let _agentListCacheTime = 0;
+const AGENT_LIST_CACHE_TTL = 5000; // 5 秒
+
 router.get('/list', (req, res) => {
   try {
+    // 缓存命中：5秒内直接返回
+    if (_agentListCache && Date.now() - _agentListCacheTime < AGENT_LIST_CACHE_TTL) {
+      return res.json(_agentListCache);
+    }
+
     const allAgents = []
     const DATA_ROOT = path.resolve(__dirname, '../../data')
 
@@ -927,6 +952,10 @@ router.get('/list', (req, res) => {
       return tb - ta
     })
 
+    // 更新缓存
+    _agentListCache = allAgents;
+    _agentListCacheTime = Date.now();
+
     res.json(allAgents)
   } catch (err) { res.status(500).json({ error: err.message }) }
 });
@@ -2361,6 +2390,7 @@ ${resultsText.join('\n\n')}
     }
 
     meta.status = 'completed';
+    flushLogBufferForConv(agentId, convId); // 刷出日志缓冲
     saveMeta(agentId, convId, meta);
 
     // ── Phase 1 MVP: 自动保存 Session 摘要到记忆 ──
@@ -2382,6 +2412,7 @@ ${resultsText.join('\n\n')}
   } catch (err) {
     console.error('[AgentChat] Error:', err.message);
     logMessageChunk(agentId, convId, `\n\n[ERROR]\n${err.message}\n\n`);
+    flushLogBufferForConv(agentId, convId); // 刷出日志缓冲
     meta.status = 'failed';
     meta.error = err.message;
     saveMeta(agentId, convId, meta);