feat(agent-chat): 修复智能体会话归属与历史路由恢复：侧边栏按当前agent过滤会话并携带agent上下文跳转，补充旧线程路径回溯到智能体工作区，防止误入通用问答，并完善输入框记忆按钮显隐与侧边栏展开入口，提升体验一致性。

frontend-web/src/components/workspace/agents/agent-chat-sidebar.tsx

@@ -64,7 +64,7 @@ import {
 import {
   useDeleteThread,
   useRenameThread,
-  useThreads,
+  useThreadsPage,
   useToggleThreadFavorite,
   useToggleThreadPin,
 } from "@/core/threads/hooks";
@@ -351,8 +351,8 @@ export function AgentChatSidebar({ activeAgentId }: { activeAgentId?: string })
 }
 
 /**
- * 「最近的对话」面板（参考首页 GeneralQaSidebar 的「最近的对话」区块）。
+ * 当前智能体的「最近对话」面板（参考首页 GeneralQaSidebar 的「最近的对话」区块）。
- * 跨智能体的近期会话，点击打开；支持重命名/置顶/收藏/分享/导出/删除。
+ * 按 agent_id 在服务端过滤；支持重命名/置顶/收藏/分享/导出/删除。
  */
 function RecentChatsPane({ activeAgentId }: { activeAgentId?: string }) {
   const { t } = useI18n();
@@ -361,7 +361,12 @@ function RecentChatsPane({ activeAgentId }: { activeAgentId?: string }) {
   const pathOf = usePathOfThread();
 
   const { thread_id: threadIdFromPath } = useParams<{ thread_id: string }>();
-  const { data: threads = [] } = useThreads();
+  const { data: threadPage } = useThreadsPage({
+    page: 1,
+    pageSize: 50,
+    metadata: { agent_id: activeAgentId ?? "" },
+  });
+  const threads = threadPage?.threads ?? [];
   const { mutate: deleteThread } = useDeleteThread();
   const { mutate: renameThread } = useRenameThread();
   const { toggle: togglePin } = useToggleThreadPin();
@@ -373,8 +378,8 @@ function RecentChatsPane({ activeAgentId }: { activeAgentId?: string }) {
   const [renameValue, setRenameValue] = useState("");
   const [shareThreadId, setShareThreadId] = useState<string | null>(null);
 
-  // 排除调度/会商/报告结构&写作配置向导等系统会话，与首页一致；
+  // 服务端先按当前智能体过滤；客户端再排除调度/会商/报告结构&写作配置向导等
-  // 智能体创建（bootstrap）会话保留展示（带机器人图标、点击回创建页）；置顶优先。
+  // 系统会话。智能体创建（bootstrap）会话保留展示（带机器人图标、点击回创建页）；置顶优先。
   const visibleThreads = useMemo(
     () => sortThreadsPinnedFirst(threads.filter((thread) => !isHiddenFromRecentChats(thread))),
     [threads],
@@ -479,7 +484,11 @@ function RecentChatsPane({ activeAgentId }: { activeAgentId?: string }) {
         ) : (
           filteredThreads.map((thread) => {
             const isBoot = isBootstrapThread(thread);
-            const href = isBoot ? bootstrapResumePath(thread.thread_id) : pathOf(thread);
+            // 正常记录依据自身保存的 agent_id 跳转；早期记录可能尚未写入
+            // agent_id，此时保留当前智能体上下文，避免从智能体页误落到通用问答。
+            const href = isBoot
+              ? bootstrapResumePath(thread.thread_id)
+              : pathOf(thread, { agent_id: activeAgentId });
             const isActive = href === pathname;
             const pinned = isThreadPinned(thread);
             const favorited = isThreadFavorite(thread);

frontend-web/src/components/workspace/input-box.tsx

@@ -758,7 +758,7 @@ export function InputBox({
                 )}
               />
             )}
-            {!frontendRagActive && !hideContextTools && !hideMemoryTool && <Tooltip
+            {!frontendRagActive && !hideContextTools && <Tooltip
               content={
                 context.writing_mode
                   ? "写作模式已开启：报告由深度研究管线按「通用分析结构」撰写，优先使用对话中已检索的资料"
@@ -813,7 +813,7 @@ export function InputBox({
                 <span className="text-xs font-normal">文件</span>
               </PromptInputButton>
             </Tooltip>}
-            {!frontendRagActive && !hideContextTools && <Tooltip
+            {!frontendRagActive && !hideContextTools && !hideMemoryTool && <Tooltip
               content={
                 memoryInjectionEnabled
                   ? "记忆注入已开启：对话前会注入历史记忆"

frontend-web/src/core/threads/utils.ts

@@ -27,6 +27,18 @@ function pickAgentRef(
   return undefined;
 }
 
+/**
+ * Return the agent that owns a thread when that ownership was persisted on
+ * either its run context or its metadata.  Keeping this in one place ensures
+ * sidebars and route recovery make the same decision for older deep links.
+ */
+export function agentRefOfThread(thread: {
+  context?: ThreadAgentRef | null;
+  metadata?: Record<string, unknown> | null;
+}): string | undefined {
+  return pickAgentRef(thread.context, thread.metadata);
+}
+
 export function pathOfThread(
   thread: ThreadRouteTarget,
   context?: ThreadAgentRef | null,
@@ -36,7 +48,7 @@ export function pathOfThread(
   const agentRef =
     typeof thread === "string"
       ? pickAgentRef(context, null)
-      : pickAgentRef(thread.context, thread.metadata);
+      : agentRefOfThread(thread) ?? pickAgentRef(context, null);
 
   return agentRef
     ? `${base}/agents/${encodeURIComponent(agentRef)}/chats/${threadId}`

frontend-web/src/pages/AgentChatPage.tsx

@@ -3,6 +3,7 @@
 import {
   BotIcon,
   Compass,
+  PanelLeftOpenIcon,
   PanelRightOpenIcon,
   PlusSquare,
 } from "lucide-react";
@@ -13,6 +14,7 @@ import { useCallback, useEffect, useMemo, useRef, useState, type ReactNode } fro
 
 import type { PromptInputMessage } from "@/components/ai-elements/prompt-input";
 import { Button } from "@/components/ui/button";
+import { useSidebarSafe } from "@/components/ui/sidebar";
 import { AgentChatSidebar } from "@/components/workspace/agents/agent-chat-sidebar";
 import { AgentDetailPanel } from "@/components/workspace/agents/agent-detail-panel";
 import { AgentQuestionChips } from "@/components/workspace/agents/agent-question-chips";
@@ -225,6 +227,7 @@ export default function AgentChatPage({
   const { t } = useI18n();
   const [showFollowups, setShowFollowups] = useState(false);
   const router = useRouter();
+  const workspaceSidebar = useSidebarSafe();
 
   const { agent_id: agentIdFromPath } = useParams<{
     agent_id: string;
@@ -806,6 +809,23 @@ export default function AgentChatPage({
             <main className="relative flex size-full min-h-0 min-w-0 flex-col">
               {/* Header in normal flow, fixed height. */}
               <header className="bg-card/90 border-border/70 flex h-12 shrink-0 items-center gap-2 border-b px-4 backdrop-blur-md">
+                {/* 工作区左栏收起后，在智能体聊天区左上角提供展开入口。 */}
+                {showAgentList &&
+                  !isEmbedded &&
+                  workspaceSidebar &&
+                  !workspaceSidebar.open && (
+                    <Button
+                      type="button"
+                      variant="ghost"
+                      size="icon-sm"
+                      onClick={workspaceSidebar.toggleSidebar}
+                      title="展开左侧栏"
+                      aria-label="展开左侧栏"
+                      className="shrink-0 text-muted-foreground hover:text-foreground"
+                    >
+                      <PanelLeftOpenIcon className="size-4" />
+                    </Button>
+                  )}
                 <div className="flex shrink-0 items-center gap-1.5 rounded-md border px-2 py-1">
                   <BotIcon className="text-primary h-3.5 w-3.5" />
                   <span
@@ -881,23 +901,6 @@ export default function AgentChatPage({
                       开始回答
                     </Button>
                   )}
-                  <Tooltip content={t.agents.newChat}>
-                    <Button
-                      size="sm"
-                      variant="secondary"
-                      onClick={() => {
-                        // 嵌入态：保持停留在通用问答右侧，开同一智能体的新对话；
-                        // 非嵌入态：走该智能体的独立新对话页（按当前路由 base）。
-                        router.push(
-                          isEmbedded
-                            ? `/page/workspace/chats/new?agent=${agent_id}`
-                            : `${agentChatsBase}/new`,
-                        );
-                      }}
-                    >
-                      <PlusSquare /> {t.agents.newChat}
-                    </Button>
-                  </Tooltip>
                   {/* 右侧智能体详情面板收起时的「展开」入口：仅收起态显示
                       （展开态的「收起」按钮在面板右上角）。桌面端专用（lg+），
                       窄屏面板走抽屉交互；嵌入态面板固定渲染，不显示该开关。 */}
@@ -919,6 +922,23 @@ export default function AgentChatPage({
                     enabled={tokenUsageEnabled}
                     messages={displayThread.messages}
                   />
+                  <Tooltip content={t.agents.newChat}>
+                    <Button
+                      size="sm"
+                      variant="secondary"
+                      onClick={() => {
+                        // 嵌入态：保持停留在通用问答右侧，开同一智能体的新对话；
+                        // 非嵌入态：走该智能体的独立新对话页（按当前路由 base）。
+                        router.push(
+                          isEmbedded
+                            ? `/page/workspace/chats/new?agent=${agent_id}`
+                            : `${agentChatsBase}/new`,
+                        );
+                      }}
+                    >
+                      <PlusSquare /> {t.agents.newChat}
+                    </Button>
+                  </Tooltip>
                   <ExportTrigger threadId={threadId} />
                   <ArtifactTrigger />
                 </div>
@@ -1101,7 +1121,6 @@ export default function AgentChatPage({
             onAskQuestion={(text) => handleSubmit({ text, files: [] })}
             collapsed={detailCollapsed}
             onCollapsedChange={setDetailCollapsed}
-            showRecentChats={!taskCtxOn}
             compactAppearanceActions={compactAppearanceActions}
           />
         </div>

frontend-web/src/pages/WorkspaceRoutes.tsx

@@ -1,7 +1,8 @@
-import type { CSSProperties, ReactNode } from 'react';
+import { useEffect, useState, type CSSProperties, type ReactNode } from 'react';
 import { Navigate, Route, Routes, useLocation, useParams } from 'react-router-dom';
 
 import { getStoredAuth } from '@/core/auth';
+import { getAPIClient } from '@/core/api';
 import { isSentimentAgentVisible } from '@/core/sentiment-agent/config';
 import {
   resolveChatsIframeEntryRedirect,
@@ -25,6 +26,7 @@ import { ArtifactsProvider } from '@/components/workspace/artifacts';
 import { DocumentRewritePresentationProvider } from '@/core/document-rewrite/context';
 
 import { RouteBaseProvider } from '@/core/route-base';
+import { agentRefOfThread } from '@/core/threads/utils';
 
 import ChatsPage from './ChatsPage';
 import ChatPage from './ChatPage';
@@ -341,12 +343,80 @@ function ChatThreadEntryRoute({
   return (
     <WorkspaceLayout {...layoutProps} defaultHistorySidebarOpen>
       <ChatRuntime>
-        <ChatPage />
+        <AgentAwareChatThreadContent />
       </ChatRuntime>
     </WorkspaceLayout>
   );
 }
 
+/**
+ * Older bookmarks and a few historic list entries use the generic
+ * ``/chats/:thread_id`` path even for an agent-owned conversation. Recover the
+ * owning agent from the persisted thread record before rendering so those
+ * links keep the agent workspace (agent list and detail panel) instead of
+ * falling back to the general Q&A page. Task workspace threads intentionally
+ * remain on their explicit task routes because their surrounding layout is
+ * part of the task context.
+ */
+function AgentAwareChatThreadContent() {
+  const { thread_id: threadId } = useParams<{ thread_id: string }>();
+  const location = useLocation();
+  const [agentId, setAgentId] = useState<string | null>(null);
+  const [resolved, setResolved] = useState(false);
+
+  useEffect(() => {
+    let cancelled = false;
+    setAgentId(null);
+    setResolved(false);
+
+    if (!threadId) {
+      setResolved(true);
+      return () => {
+        cancelled = true;
+      };
+    }
+
+    void getAPIClient()
+      .threads.get(threadId)
+      .then((thread) => {
+        if (cancelled) return;
+        const record = thread as {
+          context?: { agent_id?: string; agent_name?: string } | null;
+          metadata?: Record<string, unknown> | null;
+        };
+        // Task-bound threads need their task host to preserve the purpose gate,
+        // action partitioning, and other task-specific controls.
+        const isTaskThread = typeof record.metadata?.taskId === 'string';
+        setAgentId(isTaskThread ? null : agentRefOfThread(record) ?? null);
+      })
+      .catch(() => {
+        if (!cancelled) setAgentId(null);
+      })
+      .finally(() => {
+        if (!cancelled) setResolved(true);
+      });
+
+    return () => {
+      cancelled = true;
+    };
+  }, [threadId]);
+
+  if (!resolved) {
+    return <div className="size-full bg-background" aria-busy="true" />;
+  }
+
+  if (threadId && agentId) {
+    return (
+      <Navigate
+        replace
+        to={`/page/workspace/agents/${encodeURIComponent(agentId)}/chats/${threadId}${location.search}`}
+      />
+    );
+  }
+
+  return <ChatPage />;
+}
+
 /**
  * `chats_iframe` is reserved for the Brainy postMessage protocol. `from=iframe`
  * and `chatMode=iframe` opt into this page; ordinary iframe/Wujie embedding