diff --git a/MdePkg/Include/Library/BaseLib.h b/MdePkg/Include/Library/BaseLib.h
index 59cf4ed9f1..7e10804082 100644
--- a/MdePkg/Include/Library/BaseLib.h
+++ b/MdePkg/Include/Library/BaseLib.h
@@ -211,6 +211,7 @@ StrnLenS (
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -242,6 +243,7 @@ StrCpyS (
 
   If Length > 0 and Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Length > 0 and Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -275,6 +277,7 @@ StrnCpyS (
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -309,7 +312,8 @@ StrCatS (
   set to null.
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
-  If and Source is not aligned on a 16-bit boundary, then ASSERT().
+  If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -362,6 +366,8 @@ AsciiStrnLenS (
   Copies the string pointed to by Source (including the terminating null char)
   to the array pointed to by Destination.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -390,6 +396,8 @@ AsciiStrCpyS (
   Source to the array pointed to by Destination. If no null char is copied from
   Source, then Destination[Length] is always set to null.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -420,6 +428,8 @@ AsciiStrnCpyS (
   Appends a copy of the string pointed to by Source (including the terminating
   null char) to the end of the string pointed to by Destination.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -452,6 +462,8 @@ AsciiStrCatS (
   copied from Source, then Destination[StrLen(Destination) + Length] is always
   set to null.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
diff --git a/MdePkg/Library/BaseLib/SafeString.c b/MdePkg/Library/BaseLib/SafeString.c
index 7d7765bc01..7c1b0758f3 100644
--- a/MdePkg/Library/BaseLib/SafeString.c
+++ b/MdePkg/Library/BaseLib/SafeString.c
@@ -153,6 +153,7 @@ StrnLenS (
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -230,6 +231,7 @@ StrCpyS (
 
   If Length > 0 and Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Length > 0 and Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -318,6 +320,7 @@ StrnCpyS (
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
   If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -413,7 +416,8 @@ StrCatS (
   set to null.
 
   If Destination is not aligned on a 16-bit boundary, then ASSERT().
-  If and Source is not aligned on a 16-bit boundary, then ASSERT().
+  If Source is not aligned on a 16-bit boundary, then ASSERT().
+  If an error would be returned, then the function will also ASSERT().
 
   @param  Destination              A pointer to a Null-terminated Unicode string.
   @param  DestMax                  The maximum number of Destination Unicode
@@ -557,6 +561,8 @@ AsciiStrnLenS (
   Copies the string pointed to by Source (including the terminating null char)
   to the array pointed to by Destination.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -628,6 +634,8 @@ AsciiStrCpyS (
   Source to the array pointed to by Destination. If no null char is copied from
   Source, then Destination[Length] is always set to null.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -710,6 +718,8 @@ AsciiStrnCpyS (
   Appends a copy of the string pointed to by Source (including the terminating
   null char) to the end of the string pointed to by Destination.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.
@@ -800,6 +810,8 @@ AsciiStrCatS (
   copied from Source, then Destination[StrLen(Destination) + Length] is always
   set to null.
 
+  If an error would be returned, then the function will also ASSERT().
+
   @param  Destination              A pointer to a Null-terminated Ascii string.
   @param  DestMax                  The maximum number of Destination Ascii
                                    char, including terminating null char.