diff --git a/source/s3_request_messages.c b/source/s3_request_messages.c
index 44e2c457..eecaef30 100644
--- a/source/s3_request_messages.c
+++ b/source/s3_request_messages.c
@@ -471,6 +471,7 @@ struct aws_http_message *aws_s3_get_source_object_size_message_new(
         goto error_cleanup;
     }
     if (source_uri != NULL && source_uri->self_size > 0) {
+        /* Parse source host header and path from the provided URI */
         struct aws_byte_cursor host = *aws_uri_host_name(source_uri);
         struct aws_byte_cursor path = *aws_uri_path(source_uri);
         struct aws_http_header host_header = {
@@ -487,6 +488,7 @@ struct aws_http_message *aws_s3_get_source_object_size_message_new(
         return message;
     }
 
+    /* Parse the source host header and path from the x-amz-copy-source header and the destination URI */
     struct aws_byte_buf head_object_host_header;
     AWS_ZERO_STRUCT(head_object_host_header);