diff --git a/.env.example b/.env.example
index 80b9a56..79403ec 100644
--- a/.env.example
+++ b/.env.example
@@ -7,7 +7,7 @@ SEARCH_API=tavily
 TAVILY_API_KEY=tvly-xxx
 # JINA_API_KEY=jina_xxx # Optional, default is None
 
-# Volcengine TTS
+# Optional, volcengine TTS for generating podcast
 VOLCENGINE_TTS_APPID=xxx
 VOLCENGINE_TTS_ACCESS_TOKEN=xxx
 # VOLCENGINE_TTS_CLUSTER=volcano_tts # Optional, default is volcano_tts