新会话默认连接agent列表里面的第一个agent，不再固定使用codex

src/components/conversations/conversation-detail-panel.tsx

@@ -694,6 +694,12 @@ const ConversationTabView = memo(function ConversationTabView({
       setDraftAgentType(nextAgentType)
       setModeId(null)
       setAgentConnectError(null)
+
+      // If not yet connected, just update state — auto-connect will use the
+      // new agentType once canAutoConnect is satisfied.
+      const s = connStatusRef.current
+      if (!s || s === "disconnected" || s === "error") return
+
       connDisconnect()
         .catch((e) =>
           console.error("[ConversationTabView] disconnect old agent:", e)
@@ -1090,7 +1096,7 @@ export function ConversationDetailPanel() {
 
   const handleNewConversation = useCallback(() => {
     if (!folder) return
-    openNewConversationTab("codex", folder.path)
+    openNewConversationTab(folder.path)
   }, [folder, openNewConversationTab])
 
   const handleCloseActiveTab = useCallback(() => {
@@ -1103,18 +1109,9 @@ export function ConversationDetailPanel() {
     if (!folder) return
 
     if (hasNoTabs) {
-      openNewConversationTab(
-        newConversation?.agentType ?? "codex",
-        newConversation?.workingDir ?? folder.path
-      )
+      openNewConversationTab(newConversation?.workingDir ?? folder.path)
     }
-  }, [
-    folder,
-    hasNoTabs,
-    newConversation?.agentType,
-    newConversation?.workingDir,
-    openNewConversationTab,
-  ])
+  }, [folder, hasNoTabs, newConversation?.workingDir, openNewConversationTab])
 
   const canTile = isTileMode && tabs.length > 1
 

src/components/conversations/sidebar-conversation-list.tsx

@@ -373,7 +373,7 @@ export function SidebarConversationList({
 
   const handleNewConversation = useCallback(() => {
     if (!folder) return
-    openNewConversationTab("codex", folder.path)
+    openNewConversationTab(folder.path)
   }, [folder, openNewConversationTab])
 
   const handleImport = useCallback(async () => {

src/components/layout/folder-title-bar.tsx

@@ -151,7 +151,7 @@ export function FolderTitleBar() {
       if (matchShortcutEvent(e, shortcuts.new_conversation)) {
         if (!folderPath) return
         e.preventDefault()
-        openNewConversationTab("codex", folderPath)
+        openNewConversationTab(folderPath)
         return
       }
       if (matchShortcutEvent(e, shortcuts.open_folder)) {

src/components/layout/sidebar.tsx

@@ -21,7 +21,7 @@ export function Sidebar() {
 
   const handleNewConversation = useCallback(() => {
     if (!folder) return
-    openNewConversationTab("codex", folder.path)
+    openNewConversationTab(folder.path)
   }, [folder, openNewConversationTab])
 
   if (!isOpen) return null

src/contexts/tab-context.tsx

@@ -19,6 +19,7 @@ import type {
   ConversationStatus,
   OpenedConversation,
 } from "@/lib/types"
+import { AGENT_DISPLAY_ORDER } from "@/lib/types"
 
 interface TabItemInternal {
   id: string
@@ -54,7 +55,7 @@ interface TabContextValue {
   switchTab: (tabId: string) => void
   pinTab: (tabId: string) => void
   toggleTileMode: () => void
-  openNewConversationTab: (agentType: AgentType, workingDir: string) => void
+  openNewConversationTab: (workingDir: string) => void
   bindConversationTab: (
     tabId: string,
     conversationId: number,
@@ -419,7 +420,7 @@ export function TabProvider({ children }: TabProviderProps) {
       id: makeNewConversationTabId(),
       kind: "conversation",
       conversationId: null,
-      agentType: preferred?.agentType ?? "codex",
+      agentType: AGENT_DISPLAY_ORDER[0],
       title: t("newConversation"),
       isPinned: true,
       workingDir: preferred?.workingDir ?? folder?.path,
@@ -553,18 +554,27 @@ export function TabProvider({ children }: TabProviderProps) {
   )
 
   const openNewConversationTab = useCallback(
-    (agentType: AgentType, workingDir: string) => {
+    (workingDir: string) => {
       const existingTab = rawTabsRef.current.find(
-        (t) => t.conversationId == null && t.agentType === agentType
+        (t) => t.conversationId == null
       )
 
       if (existingTab) {
+        // Update workingDir if it differs from the request
+        if (existingTab.workingDir !== workingDir) {
+          setTabs((prev) =>
+            prev.map((t) =>
+              t.id === existingTab.id ? { ...t, workingDir } : t
+            )
+          )
+        }
         setActiveTabId(existingTab.id)
         syncFolderContext(existingTab)
         activateConversationPane()
         return
       }
 
+      const agentType = AGENT_DISPLAY_ORDER[0]
       const tabId = makeNewConversationTabId()
       const newTab: TabItemInternal = {
         id: tabId,