diff --git a/scripts/gateway-watchdog.sh b/scripts/gateway-watchdog.sh
index 1427d45..30200c7 100755
--- a/scripts/gateway-watchdog.sh
+++ b/scripts/gateway-watchdog.sh
@@ -4,7 +4,7 @@
 # 机制：
 #   1. 检查最近 CHECK_WINDOW 秒内的 session jsonl 日志
 #   2. 统计 429 错误次数（errorCode=1305 或 errorMessage 含 "429"）
-#   3. 连续 THRESHOLD 次检测都发现新 429 → 重启 Gateway
+#   3. CHECK_WINDOW 内 429 总数 >= THRESHOLD → 重启 Gateway
 #
 # 部署：cron 每分钟执行一次
 #   * * * * * /Users/chufeng/.openclaw/sanguo_projects/sanguo_moziplus_v2/scripts/gateway-watchdog.sh >> /tmp/gateway-watchdog.log 2>&1
@@ -14,9 +14,17 @@ set -euo pipefail
 # crontab 环境下 PATH 不完整，补上
 export PATH="/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:$PATH"
 
+# === flock 防并发 ===
+LOCK_FILE="/tmp/gateway-watchdog.lock"
+exec 9>"$LOCK_FILE"
+if ! flock -n 9; then
+    exit 0
+fi
+
 # === 配置 ===
 CHECK_WINDOW=120          # 检查最近多少秒的日志
-THRESHOLD=3               # 连续检测到多少次 429 才重启
+THRESHOLD=3               # CHECK_WINDOW 内发现多少个 429 就重启
+MTIME_BUFFER=180          # 文件 mtime 阈值（CHECK_WINDOW + buffer，防漏检）
 STATE_FILE="/tmp/gateway-watchdog-429-count"
 LOG_DIR="/Users/chufeng/.openclaw/agents"
 RESTART_CMD="openclaw gateway restart"
@@ -33,20 +41,22 @@ count_recent_429() {
     local cutoff=$(date -u -v-${CHECK_WINDOW}S '+%Y-%m-%dT%H:%M:%S' 2>/dev/null || date -u -d "${CHECK_WINDOW} seconds ago" '+%Y-%m-%dT%H:%M:%S')
     local count=0
 
-    # 只看 session jsonl（排除 trajectory）
     for jsonl in "$LOG_DIR"/*/sessions/*.jsonl; do
+        # 排除 trajectory 和 checkpoint 文件
         [[ "$jsonl" == *"trajectory"* ]] && continue
+        [[ "$jsonl" == *"checkpoint"* ]] && continue
         [ -f "$jsonl" ] || continue
-        # 只看最近修改的文件（性能优化）
+
+        # mtime 过滤（加 buffer 防漏检）
         local mtime
         mtime=$(stat -f '%m' "$jsonl" 2>/dev/null | tr -d ' \n' || stat -c '%Y' "$jsonl" 2>/dev/null | tr -d ' \n')
         [ -z "$mtime" ] && continue
         local now
         now=$(date +%s)
         local age=$(( now - mtime ))
-        # 文件超过 CHECK_WINDOW 秒没修改就跳过
-        [ "$age" -gt "$CHECK_WINDOW" ] && continue
-        # 文件小于 100 字节就跳过（空/刚创建）
+        [ "$age" -gt "$MTIME_BUFFER" ] && continue
+
+        # 跳过空文件
         local fsize
         fsize=$(wc -c < "$jsonl" | tr -d ' ')
         [ "$fsize" -lt 100 ] && continue
@@ -55,7 +65,6 @@ count_recent_429() {
         local found=0
         found=$(grep -c '"errorCode".*"1305"\|"errorMessage".*"429"' "$jsonl" 2>/dev/null || true)
         [ -z "$found" ] && found=0
-        # 进一步过滤：只统计时间窗口内的
         if [ "$found" -gt 0 ]; then
             local recent
             recent=$(python3 -c "
@@ -72,7 +81,7 @@ with open('${jsonl}') as f:
             msg = d.get('message', {})
             if msg.get('stopReason') == 'error':
                 err = str(msg.get('errorMessage', ''))
-                code = str(msg.get('errorCode', ''))
+                code = msg.get('errorCode') or ''
                 if '429' in err or '1305' in code:
                     count += 1
         except:
@@ -98,29 +107,19 @@ fi
 # 2. 统计最近 429 错误
 four29_count=$(count_recent_429)
 
-# 3. 读取连续计数
-consecutive=0
-if [ -f "$STATE_FILE" ]; then
-    consecutive=$(cat "$STATE_FILE")
-fi
-
-# 4. 判断
-if [ "$four29_count" -gt 0 ]; then
-    consecutive=$(( consecutive + 1 ))
-    log "429 detected: ${four29_count} recent errors, consecutive=${consecutive}/${THRESHOLD}"
-else
-    if [ "$consecutive" -gt 0 ]; then
-        log "429 cleared (was ${consecutive} consecutive, now 0)"
-    fi
-    consecutive=0
-fi
-
-echo "$consecutive" > "$STATE_FILE"
-
-# 5. 达到阈值 → 重启
-if [ "$consecutive" -ge "$THRESHOLD" ]; then
-    log "ALERT: ${consecutive} consecutive 429 detections, restarting Gateway"
+# 3. 判断：CHECK_WINDOW 内 429 总数 >= THRESHOLD → 重启
+if [ "$four29_count" -ge "$THRESHOLD" ]; then
+    log "ALERT: ${four29_count} 429 errors in last ${CHECK_WINDOW}s (threshold=${THRESHOLD}), restarting Gateway"
     $RESTART_CMD 2>&1
     log "Gateway restart completed"
+    echo "$four29_count" > "$STATE_FILE"
+elif [ "$four29_count" -gt 0 ]; then
+    log "429 detected: ${four29_count} errors in last ${CHECK_WINDOW}s (threshold=${THRESHOLD}, no restart)"
+    echo "$four29_count" > "$STATE_FILE"
+else
+    # 只在有前次记录时打印 clear
+    if [ -f "$STATE_FILE" ] && [ "$(cat "$STATE_FILE")" != "0" ]; then
+        log "429 cleared"
+    fi
     echo 0 > "$STATE_FILE"
 fi