diff --git a/src/mir/loop_pattern_detection/mod.rs b/src/mir/loop_pattern_detection/mod.rs
index c353b4fb..ecd72a97 100644
--- a/src/mir/loop_pattern_detection/mod.rs
+++ b/src/mir/loop_pattern_detection/mod.rs
@@ -329,6 +329,12 @@ pub fn classify_with_diagnosis(features: &LoopFeatures) -> (LoopPatternKind, Str
 // ============================================================================
 // Legacy Detection Functions (Phase 188)
 // ============================================================================
+//
+// NOTE (Phase 179): These functions are still actively used by pattern lowerers.
+// The term "legacy" refers to Phase 188 implementation style (name-based detection),
+// not deprecation status. Do NOT move to legacy/ subdirectory - still production code.
+//
+// Future work: Gradually migrate to Phase 194+ structure-based detection (extract_features/classify).
 
 // ============================================================================
 // Pattern 1: Simple While Loop