diff --git a/source/common/http/filter_manager.h b/source/common/http/filter_manager.h
index 24070f66956d..72e54caef6b1 100644
--- a/source/common/http/filter_manager.h
+++ b/source/common/http/filter_manager.h
@@ -901,11 +901,13 @@ class FilterManager : public ScopeTrackedObject,
     uint32_t filter_call_state_{0};
 
     // Set after decoder filter chain has completed iteration. Prevents further calls to decoder
-    // filters.
+    // filters. This flag is used to determine stream completion when the independent half-close is
+    // enabled.
     bool decoder_filter_chain_complete_ : 1;
 
     // Set after encoder filter chain has completed iteration. Prevents further calls to encoder
-    // filters.
+    // filters. This flag is used to determine stream completion when the independent half-close is
+    // enabled.
     bool encoder_filter_chain_complete_ : 1;
 
     // Set `true` when the filter manager observes end stream on the decoder path (from downstream