diff --git a/tests/error_display.rs b/tests/error_display.rs
index b79b3149..7db8a9b8 100644
--- a/tests/error_display.rs
+++ b/tests/error_display.rs
@@ -2,6 +2,8 @@
 //!
 //! Verifies that error types provide human-readable messages via Display
 //! and correctly expose underlying error sources via `Error::source`.
+//! Implementing these traits keeps logs clear for operators,
+//! and surfaces causal chains so developers can diagnose issues.
 
 use std::error::Error;