diff --git a/docutranslate/agents/agent.py b/docutranslate/agents/agent.py
index 9b2ceb5..a009315 100644
--- a/docutranslate/agents/agent.py
+++ b/docutranslate/agents/agent.py
@@ -570,10 +570,13 @@ class Agent:
         if thinking_mode_result is None:
             return
         field_thinking, val_enable, val_disable = thinking_mode_result
-        if self.thinking == "enable":
-            data[field_thinking] = val_enable
-        elif self.thinking == "disable":
-            data[field_thinking] = val_disable
+        value = val_enable if self.thinking == "enable" else val_disable
+        # extra_body 是 OpenAI SDK 约定；本项目用 httpx 直接发请求，
+        # 必须把里面的字段提到顶层，DashScope / GLM 等才会识别。
+        if field_thinking == "extra_body" and isinstance(value, dict):
+            data.update(value)
+        else:
+            data[field_thinking] = value
 
     def _normalize_mt_lang(self, lang: str | None) -> str | None:
         if lang is None: