diff --git a/src/main/resources/static/js/APITester.js b/src/main/resources/static/js/APITester.js
index c9aaead..fbdeafa 100644
--- a/src/main/resources/static/js/APITester.js
+++ b/src/main/resources/static/js/APITester.js
@@ -776,6 +776,8 @@ class APITester {
                 },
                 error: function (response, textStatus, errorThrown) {
                     me.hideLoadingOverlay();
+                    $('.toast-body').text(response.responseJSON.error);
+                    $('.toast').toast('show');
                 },
                 complete: function () {
                     let endTime = new Date().getTime();
@@ -804,6 +806,8 @@ class APITester {
             },
             error: function (response, textStatus, errorThrown) {
                 me.hideLoadingOverlay();
+                $('.toast-body').text(response.responseJSON.error);
+                $('.toast').toast('show');
             },
             complete: function () {
                 me.renderCollections();
@@ -826,6 +830,8 @@ class APITester {
             },
             error: function (response, textStatus, errorThrown) {
                 me.hideLoadingOverlay();
+                $('.toast-body').text(response.responseJSON.error);
+                $('.toast').toast('show');
             },
             complete: function () {
                 me.loadCollections();
@@ -845,6 +851,8 @@ class APITester {
             data: JSON.stringify({id: id, name: name}),
             error: function (response, textStatus, errorThrown) {
                 me.hideLoadingOverlay();
+                $('.toast-body').text(response.responseJSON.error);
+                $('.toast').toast('show');
             },
             complete: function () {
                 me.loadCollections();
@@ -866,9 +874,9 @@ class APITester {
             success: function () {
             },
             error: function (response, textStatus, errorThrown) {
-                let error = response.responseJSON;
                 me.hideLoadingOverlay();
-                alert(error.error);
+                $('.toast-body').text(response.responseJSON.error);
+                $('.toast').toast('show');
             },
             complete: function () {
                 me.loadCollections();
@@ -1054,6 +1062,7 @@ class APITester {
             success: function (data) {
             },
             error: function (response, textStatus, errorThrown) {
+                $('.toast-body').text(response.responseJSON.error);
                 me.hideLoadingOverlay();
             },
             complete: function () {