diff --git a/astrbot/core/provider/sources/openai_source.py b/astrbot/core/provider/sources/openai_source.py
index 8aa2778f1b..044aad0203 100644
--- a/astrbot/core/provider/sources/openai_source.py
+++ b/astrbot/core/provider/sources/openai_source.py
@@ -594,12 +594,20 @@ def _is_empty(content: Any) -> bool:
             tool_calls = msg.get("tool_calls")
             reasoning_content = msg.get("reasoning_content")
 
-            if _is_empty(content) and not tool_calls and not reasoning_content:
-                logger.warning(f"过滤第 {idx} 条空 assistant 消息 (无工具调用)")
-                continue
-
-            if _is_empty(content) and tool_calls:
-                msg["content"] = None
+            if _is_empty(content) and not tool_calls:
+                if not reasoning_content:
+                    # 三者全空，真正的垃圾消息，丢弃
+                    logger.debug(f"过滤第 {idx} 条空 assistant 消息 (无 content | tool_calls | reasoning_content)")
+                    continue
+                else:
+                    # ⭐ 有 reasoning_content 但没有 content 和 tool_calls
+                    # 不能丢（推理模型需要 reasoning 历史）
+                    # 但 API 要求 content 或 tool_calls 至少有一个
+                    # → 设空字符串占位，满足校验
+                    msg["content"] = ""
+
+            elif _is_empty(content) and tool_calls:
+                msg["content"] = None   # 有 tool_calls，按 OpenAI 规范
 
             cleaned.append(msg)