diff --git a/plugins/message_summary/config.toml b/plugins/message_summary/config.toml
index f584b39..8544a9b 100644
--- a/plugins/message_summary/config.toml
+++ b/plugins/message_summary/config.toml
@@ -18,3 +18,11 @@ image_format = "png"
 summary_image_mode = "template"
 # 总结卡片模板路径（相对项目根目录）
 summary_image_template_path = "plugins/message_summary/templates/gemini_summary_card.html"
+# 模板模式截图视口配置（仅 template 模式生效）
+# 说明：
+# 1. 这里可以覆盖 md2image 默认 780 宽；
+# 2. 模板卡片宽度约 420，截图建议 460~520 区间；
+# 3. scale 提高后字体与线条会更清晰。
+template_viewport_width = 500
+template_viewport_height = 960
+template_device_scale_factor = 2.0
diff --git a/plugins/message_summary/main.py b/plugins/message_summary/main.py
index df7b485..913ebf4 100644
--- a/plugins/message_summary/main.py
+++ b/plugins/message_summary/main.py
@@ -117,6 +117,13 @@ class MessageSummaryPlugin(MessagePluginInterface):
             self._template_viewport_width = int(output_config.get("template_viewport_width", 780))
             self._template_viewport_height = int(output_config.get("template_viewport_height", 960))
             self._template_device_scale_factor = float(output_config.get("template_device_scale_factor", 1.2))
+            # 启动时输出模板截图视口参数，便于排查“配置未生效仍是 780 宽”的问题。
+            self.LOG.info(
+                f"[{self.name}] 模板截图视口: "
+                f"width={self._template_viewport_width}, "
+                f"height={self._template_viewport_height}, "
+                f"scale={self._template_device_scale_factor}"
+            )
             self.llm_client = UnifiedLLMClient(api_config)
             self._api_mode = self.llm_client.mode or self._api_mode
             self._response_mode = self.llm_client.response_mode or self._response_mode