diff --git a/backend/internal/session/redis.go b/backend/internal/session/redis.go
index c497dd5..c698502 100644
--- a/backend/internal/session/redis.go
+++ b/backend/internal/session/redis.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/hhs/camtalk/internal/logger"
 	"github.com/hhs/camtalk/internal/models"
+	"github.com/hhs/camtalk/internal/util"
 )
 
 // RedisManager 基于 Redis 的 SessionManager 实现。
@@ -285,7 +286,10 @@ func (m *RedisManager) GetHistory(ctx context.Context, sessionID string, limit i
 		}
 		var msg models.Message
 		if err := json.Unmarshal([]byte(raw), &msg); err != nil {
-			logger.Log.Warnw("invalid history entry", "session", sessionID, "raw", raw)
+			logger.Log.Warnw("invalid history entry",
+				"session", sessionID,
+				"raw_len", len(raw),
+				"raw_preview", util.Truncate(raw, 100))
 			continue
 		}
 		msgs = append(msgs, msg)