diff --git a/backend/ai-core/internal/background/thinker.go b/backend/ai-core/internal/background/thinker.go
index 62df366..50d0e26 100644
--- a/backend/ai-core/internal/background/thinker.go
+++ b/backend/ai-core/internal/background/thinker.go
@@ -363,6 +363,7 @@ func (t *Thinker) SetEmotionTracker(et *persona.EmotionTracker) {
 // Called by the ai-core presence endpoint when gateway detects connect/disconnect.
 func (t *Thinker) UpdatePresence(online bool, sessionID string) {
 	t.muLock()
+	defer t.muUnlock()
 	wasOffline := !t.isUserOnline()
 	t.setUserOnline(online)
 	t.lastOnlineChange = time.Now()
@@ -370,7 +371,7 @@ func (t *Thinker) UpdatePresence(online bool, sessionID string) {
 		t.userSessionID = sessionID
 		t.activeSessionID = sessionID
 	}
-	t.muUnlock()
+
 
 	if online && wasOffline {
 		log.Printf("[后台思考] 用户上线 (session=%s)，触发重连思考", sessionID)
@@ -390,6 +391,7 @@ func (t *Thinker) UpdatePresence(online bool, sessionID string) {
 // Called by the internal reminder-trigger endpoint when a reminder fires.
 func (t *Thinker) TriggerReminderMessage(userID, sessionID, message string) {
 	t.muLock()
+	defer t.muUnlock()
 	pusher := t.messagePusher
 	pushSessionID := sessionID
 	if pushSessionID == "" {
@@ -398,7 +400,7 @@ func (t *Thinker) TriggerReminderMessage(userID, sessionID, message string) {
 	if pushSessionID == "" {
 		pushSessionID = t.adminSessionID
 	}
-	t.muUnlock()
+
 
 	if pusher != nil && message != "" {
 		log.Printf("[提醒推送] 推送LLM提醒: user=%s session=%s msg=%s", userID, pushSessionID, message)
@@ -409,8 +411,9 @@ func (t *Thinker) TriggerReminderMessage(userID, sessionID, message string) {
 // PushPlatformMessage pushes a message to a platform channel via the platform pusher.
 func (t *Thinker) PushPlatformMessage(target ProactiveTarget, message string) {
 	t.muLock()
+	defer t.muUnlock()
 	pusher := t.platformMessagePusher
-	t.muUnlock()
+
 	if pusher != nil {
 		log.Printf("[平台推送] target=%s/%s group=%s msg=%s", target.Platform, target.ChatType, target.GroupID, message)
 		pusher(target, message)
@@ -555,9 +558,10 @@ func (t *Thinker) restoreContext() {
 	}
 	if !latest.IsZero() && time.Since(latest) < 24*time.Hour {
 		t.muLock()
+		defer t.muUnlock()
 		t.lastUserMessage = latest
 		t.setLastUser(latest)
-		t.muUnlock()
+
 		log.Printf("[后台思考] 上下文已恢复: 最近活动 %v 前", time.Since(latest).Round(time.Second))
 	} else if !latest.IsZero() {
 		log.Printf("[后台思考] 上下文恢复跳过: 最近消息 %v 前(>24h)，使用默认值", time.Since(latest).Round(time.Second))
@@ -669,8 +673,9 @@ func (t *Thinker) TriggerPostChatThink() {
 	}
 
 	t.muLock()
+	defer t.muUnlock()
 	canThink := time.Since(t.lastThinkTimeAtomic()) >= t.minThinkGap
-	t.muUnlock()
+
 
 	if !canThink {
 		log.Printf("[后台思考] 距上次思考仅 %v，跳过 (最小间隔=%v)", time.Since(t.lastThinkTimeAtomic()), t.minThinkGap)
@@ -738,9 +743,10 @@ func (t *Thinker) resetSilenceTimer() {
 		case <-t.silenceTimer.C:
 			// 再次检查：用户是否真的沉默了足够久
 			t.muLock()
+			defer t.muUnlock()
 			silenceDuration := time.Since(t.lastUserTime())
 			canThink := time.Since(t.lastThinkTimeAtomic()) >= t.minThinkGap
-			t.muUnlock()
+
 
 			if silenceDuration < t.silenceTimeout {
 				log.Printf("[后台思考] 静默检测触发但用户已活动，跳过 (实际静默=%v)", silenceDuration)
@@ -855,6 +861,7 @@ func (t *Thinker) performPlatformObservation() {
 
 	observationContent := fmt.Sprintf("[平台观察 %s]\n%s", time.Now().In(t.timeLocation).Format("15:04"), result.Summary)
 	t.muLock()
+	defer t.muUnlock()
 	t.pendingThoughts = append(t.pendingThoughts, &PendingThought{
 		Content:   observationContent,
 		CreatedAt: time.Now(),
@@ -863,7 +870,7 @@ func (t *Thinker) performPlatformObservation() {
 	if len(t.pendingThoughts) > 10 {
 		t.pendingThoughts = t.pendingThoughts[len(t.pendingThoughts)-10:]
 	}
-	t.muUnlock()
+
 
 	log.Printf("[后台思考] 平台观察摘要已生成 (长度=%d, 需要关注=%v)", len(result.Summary), result.NeedsAttention)
 }
@@ -887,9 +894,10 @@ func (t *Thinker) lightThinkLoop() {
 			return
 		case <-time.After(t.lightThinkInterval):
 			t.muLock()
+			defer t.muUnlock()
 			sinceLastUser := time.Since(t.lastUserTime())
 			sinceLastThink := time.Since(t.lastThinkTimeAtomic())
-			t.muUnlock()
+
 
 			// Skip if user was active recently (last 30s).
 			if sinceLastUser < 30*time.Second {
@@ -948,8 +956,9 @@ func (t *Thinker) performLightThink() {
 	if strings.Contains(content, "【需要深思】") {
 		log.Println("[轻量思考] 检测到【需要深思】，唤醒深度思考...")
 		t.muLock()
+		defer t.muUnlock()
 		canDeep := time.Since(t.lastThinkTimeAtomic()) >= t.minThinkGap
-		t.muUnlock()
+
 		if canDeep {
 			t.performThink("light_wake")
 		} else {
@@ -963,13 +972,14 @@ func (t *Thinker) performLightThink() {
 		if topic != "" {
 			log.Printf("[轻量思考] 话题发起: %s", topic)
 			t.muLock()
+			defer t.muUnlock()
 			pusher := t.messagePusher
 			sessionID := t.activeSessionID
 			if sessionID == "" {
 				sessionID = t.adminSessionID
 			}
 			canPush := time.Since(t.lastProactiveTime()) >= t.proactiveMsgMinGap
-			t.muUnlock()
+
 			if pusher != nil && canPush {
 				go pusher(t.adminUserID, sessionID, topic)
 				if t.convStore != nil && sessionID != "" {
@@ -1070,13 +1080,14 @@ func (t *Thinker) HasPendingThoughts() bool {
 // 强制执行最小间隔，防止并发调用或 bug 导致 LLM 配额被快速消耗。
 func (t *Thinker) performThink(triggerReason string) {
 	t.muLock()
+	defer t.muUnlock()
 	gapSinceLast := time.Since(t.lastThinkTimeAtomic())
 	minGap := t.minThinkGap
 	if minGap <= 0 {
 		minGap = 5 * time.Second // 默认最小间隔 5 秒
 	}
 	if gapSinceLast < minGap {
-		t.muUnlock()
+
 		log.Printf("[后台思考] 距上次思考仅 %v，跳过 (最小间隔=%v, 触发原因=%s)", gapSinceLast.Round(time.Second), minGap, triggerReason)
 		return
 	}
@@ -1090,14 +1101,16 @@ func (t *Thinker) performThink(triggerReason string) {
 	ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
 	defer cancel()
 	t.muLock()
+	defer t.muUnlock()
 	t.thinkCancel = cancel
-	t.muUnlock()
+
 
 	// 0. 让步于前台——如果用户最近有活动（非post_chat），跳过本次思考。
 	if triggerReason != "post_chat" {
 		t.muLock()
+		defer t.muUnlock()
 		sinceLastUser := time.Since(t.lastUserTime())
-		t.muUnlock()
+
 		if sinceLastUser < 10*time.Second {
 			log.Printf("[后台思考] 用户 %v 前有活动，让步于前台回复，跳过思考", sinceLastUser.Round(time.Second))
 			return
@@ -1109,8 +1122,9 @@ func (t *Thinker) performThink(triggerReason string) {
 	// 0. 让步于前台——如果用户最近有活动（非post_chat），跳过本次思考。
 	if triggerReason != "post_chat" {
 		t.muLock()
+		defer t.muUnlock()
 		sinceLastUser := time.Since(t.lastUserTime())
-		t.muUnlock()
+
 		if sinceLastUser < 10*time.Second {
 			log.Printf("[后台思考] 用户 %v 前有活动，让步于前台回复，跳过思考", sinceLastUser.Round(time.Second))
 			return
@@ -1128,11 +1142,12 @@ func (t *Thinker) performThink(triggerReason string) {
 	var convHistory []model.LLMMessage
 	if t.convStore != nil {
 		t.muLock()
+		defer t.muUnlock()
 		sessionID := t.activeSessionID
 		if sessionID == "" {
 			sessionID = t.adminSessionID
 		}
-		t.muUnlock()
+
 		if sessionID != "" {
 			convHistory = t.convStore.GetHistory(sessionID, 30)
 			if len(convHistory) > 0 {
@@ -1245,13 +1260,14 @@ func (t *Thinker) performThink(triggerReason string) {
 	var platformObservation string
 	if triggerReason == "periodic" || triggerReason == "post_chat" {
 		t.muLock()
+		defer t.muUnlock()
 		for i := len(t.pendingThoughts) - 1; i >= 0; i-- {
 			if strings.HasPrefix(t.pendingThoughts[i].Content, "[平台观察") {
 				platformObservation = t.pendingThoughts[i].Content
 				break
 			}
 		}
-		t.muUnlock()
+
 	}
 
 	// 5. 构建思考提示词（根据触发原因调整）
@@ -1395,6 +1411,7 @@ func (t *Thinker) performThink(triggerReason string) {
 					adapterName, groupID := parts[0], parts[1]
 					// Find the channel to get the correct platform type.
 					t.muLock()
+					defer t.muUnlock()
 					var platform string
 					for _, ch := range t.platformChannels {
 						if ch.AdapterName == adapterName && ch.ChannelID == groupID && ch.ChannelType == "group" {
@@ -1402,7 +1419,7 @@ func (t *Thinker) performThink(triggerReason string) {
 							break
 						}
 					}
-					t.muUnlock()
+
 					if platform == "" {
 						platform = "obv11" // fallback
 					}
@@ -1648,8 +1665,9 @@ func (t *Thinker) buildThinkingUserPrompt(
 		sb.WriteString("刚有人和你聊完天。你想自然地在心里回味一下刚才的对话……\n")
 	case "silence":
 		t.muLock()
+		defer t.muUnlock()
 		silenceDuration := time.Since(t.lastUserTime())
-		t.muUnlock()
+
 		sb.WriteString(fmt.Sprintf("已经大约 %s 没有说话了。你有点想知道大家在做什么……\n",
 			formatDurationHuman(silenceDuration)))
 	default:
@@ -1747,11 +1765,12 @@ func (t *Thinker) buildThinkingUserPrompt(
 
 		// OBv11 platform identity and available channels for proactive messaging.
 		t.muLock()
+		defer t.muUnlock()
 		qqChannels := t.platformChannels
 		botUIDs := t.botUIDs
 		activeSID := t.activeSessionID
 		lastMsgTime := t.lastUserTime()
-		t.muUnlock()
+
 		if len(qqChannels) > 0 {
 			sb.WriteString("\n\n【你的平台身份与可用频道】\n")
 
@@ -2066,6 +2085,7 @@ func (t *Thinker) extractProactiveMessage(content string) (string, *ProactiveTar
 					}
 					adapterName := platform // fallback to format key
 					t.muLock()
+					defer t.muUnlock()
 					for _, ch := range t.platformChannels {
 						if ch.Platform == platform && ch.ChannelType == chatType && ch.ChannelID == channelID {
 							if ch.AdapterName != "" {
@@ -2074,7 +2094,7 @@ func (t *Thinker) extractProactiveMessage(content string) (string, *ProactiveTar
 							break
 						}
 					}
-					t.muUnlock()
+
 
 					target = &ProactiveTarget{
 						Platform: adapterName,
@@ -2657,7 +2677,8 @@ func (t *Thinker) DeadlockDetected(timeout time.Duration) bool {
 	done := make(chan struct{})
 	go func() {
 		t.muLock()
-		t.muUnlock()
+		defer t.muUnlock()
+
 		close(done)
 	}()
 	select {
@@ -2682,7 +2703,8 @@ func (t *Thinker) StartDeadlockMonitor() {
 			done := make(chan struct{})
 			go func() {
 				t.muLock()
-				t.muUnlock()
+				defer t.muUnlock()
+
 				close(done)
 			}()
 			select {