diff --git a/.env.example b/.env.example
index 1328b838..a7c0259f 100644
--- a/.env.example
+++ b/.env.example
@@ -1,3 +1,4 @@
+# Default provider is `codex_oauth` and does not require OPENAI_API_KEY.
 # LLM Providers (set the one you use)
 OPENAI_API_KEY=
 GOOGLE_API_KEY=