diff --git a/R/file_analysis.R b/R/file_analysis.R
index bfdf677..445c73d 100644
--- a/R/file_analysis.R
+++ b/R/file_analysis.R
@@ -45,8 +45,8 @@ request_file_analysis <- function(con,
 
   res <- send_request(con, request)
 
-  if (handle_err_result(res)) {
-    return(NULL)
+  if (res$type == "error") {
+    return(list(error = res$reason))
   }
 
   return(list(id = id, filetoken = filetoken, res = res))
diff --git a/R/slice.R b/R/slice.R
index 8d4b02d..bbf75cc 100644
--- a/R/slice.R
+++ b/R/slice.R
@@ -20,8 +20,8 @@ request_slice <- function(con, filetoken, criteria, id = get_new_id()) {
   )
   res <- send_request(con, request)
 
-  if (handle_err_result(res)) {
-    return(NULL)
+  if (res$type == "error") {
+    return(list(error = res$reason))
   }
 
   return(list(id = id, res = res))
diff --git a/R/utils.R b/R/utils.R
index 62e4cc1..27e5145 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -1,10 +1,3 @@
-handle_err_result <- function(res) {
-  if (res$type == "error") {
-    return(TRUE)
-  }
-  return(FALSE)
-}
-
 make_id_provider <- function(next_id = 0) {
   function() {
     next_id <<- next_id + 1