diff --git a/src/library-authoring/add-content/AddContentContainer.test.tsx b/src/library-authoring/add-content/AddContentContainer.test.tsx
index 95e9e4ccb..9587576a9 100644
--- a/src/library-authoring/add-content/AddContentContainer.test.tsx
+++ b/src/library-authoring/add-content/AddContentContainer.test.tsx
@@ -164,52 +164,6 @@ describe('<AddContentContainer />', () => {
     expect(mockShowToast).toHaveBeenCalledWith('There was an error linking the content to this collection.');
   });
 
-  it('should handle failure to paste content', async () => {
-    const { axiosMock, mockShowToast } = initializeMocks();
-    // Simulate having an HTML block in the clipboard:
-    mockClipboardHtml.applyMock();
-
-    const pasteUrl = getLibraryPasteClipboardUrl(libraryId);
-    axiosMock.onPost(pasteUrl).reply(400);
-
-    render();
-
-    const pasteButton = await screen.findByRole('button', { name: /paste from clipboard/i });
-    fireEvent.click(pasteButton);
-
-    await waitFor(() => {
-      expect(axiosMock.history.post[0].url).toEqual(pasteUrl);
-      expect(mockShowToast).toHaveBeenCalledWith('There was an error pasting the content.');
-    });
-  });
-
-  it('should handle failure to paste content and show server error if available', async () => {
-    const { axiosMock, mockShowToast } = initializeMocks();
-    // Simulate having an HTML block in the clipboard:
-    mockClipboardHtml.applyMock();
-
-    const errMsg = 'Libraries do not support this type of content yet.';
-    const pasteUrl = getLibraryPasteClipboardUrl(libraryId);
-
-    // eslint-disable-next-line prefer-promise-reject-errors
-    axiosMock.onPost(pasteUrl).reply(() => Promise.reject({
-      customAttributes: {
-        httpErrorStatus: 400,
-        httpErrorResponseData: JSON.stringify({ block_type: errMsg }),
-      },
-    }));
-
-    render();
-
-    const pasteButton = await screen.findByRole('button', { name: /paste from clipboard/i });
-    fireEvent.click(pasteButton);
-
-    await waitFor(() => {
-      expect(axiosMock.history.post[0].url).toEqual(pasteUrl);
-      expect(mockShowToast).toHaveBeenCalledWith(errMsg);
-    });
-  });
-
   it('should stop user from pasting unsupported blocks and show toast', async () => {
     const { axiosMock, mockShowToast } = initializeMocks();
     // Simulate having an HTML block in the clipboard:
@@ -227,4 +181,53 @@ describe('<AddContentContainer />', () => {
       expect(mockShowToast).toHaveBeenCalledWith(errMsg);
     });
   });
+
+  test.each([
+    {
+      label: 'should handle failure to paste content',
+      mockUrl: getLibraryPasteClipboardUrl(libraryId),
+      mockResponse: undefined,
+      expectedError: 'There was an error pasting the content.',
+      buttonName: /paste from clipboard/i,
+    },
+    {
+      label: 'should show detailed error in toast on paste failure',
+      mockUrl: getLibraryPasteClipboardUrl(libraryId),
+      mockResponse: ['library cannot have more than 100000 components'],
+      expectedError: 'There was an error pasting the content: library cannot have more than 100000 components',
+      buttonName: /paste from clipboard/i,
+    },
+    {
+      label: 'should handle failure to create content',
+      mockUrl: getCreateLibraryBlockUrl(libraryId),
+      mockResponse: undefined,
+      expectedError: 'There was an error creating the content.',
+      buttonName: /text/i,
+    },
+    {
+      label: 'should show detailed error in toast on create failure',
+      mockUrl: getCreateLibraryBlockUrl(libraryId),
+      mockResponse: 'library cannot have more than 100000 components',
+      expectedError: 'There was an error creating the content: library cannot have more than 100000 components',
+      buttonName: /text/i,
+    },
+  ])('$label', async ({
+    mockUrl, mockResponse, buttonName, expectedError,
+  }) => {
+    const { axiosMock, mockShowToast } = initializeMocks();
+    axiosMock.onPost(mockUrl).reply(400, mockResponse);
+
+    // Simulate having an HTML block in the clipboard:
+    mockClipboardHtml.applyMock();
+
+    render();
+    const button = await screen.findByRole('button', { name: buttonName });
+    fireEvent.click(button);
+
+    await waitFor(() => {
+      expect(axiosMock.history.post.length).toEqual(1);
+      expect(axiosMock.history.post[0].url).toEqual(mockUrl);
+      expect(mockShowToast).toHaveBeenCalledWith(expectedError);
+    });
+  });
 });
diff --git a/src/library-authoring/add-content/AddContentContainer.tsx b/src/library-authoring/add-content/AddContentContainer.tsx
index 3ae948b8a..0dbb2da4c 100644
--- a/src/library-authoring/add-content/AddContentContainer.tsx
+++ b/src/library-authoring/add-content/AddContentContainer.tsx
@@ -1,4 +1,5 @@
 import React, { useContext } from 'react';
+import type { MessageDescriptor } from 'react-intl';
 import { useSelector } from 'react-redux';
 import {
   Stack,
@@ -80,15 +81,21 @@ const AddContentContainer = () => {
 
   const [isAddLibraryContentModalOpen, showAddLibraryContentModal, closeAddLibraryContentModal] = useToggle();
 
-  const parsePasteErrorMsg = (error: any) => {
-    let errMsg: string;
+  const parseErrorMsg = (
+    error: any,
+    detailedMessage: MessageDescriptor,
+    defaultMessage: MessageDescriptor,
+  ) => {
     try {
-      const { customAttributes: { httpErrorResponseData } } = error;
-      errMsg = JSON.parse(httpErrorResponseData).block_type;
+      const { response: { data } } = error;
+      const detail = data && (Array.isArray(data) ? data.join() : String(data));
+      if (detail) {
+        return intl.formatMessage(detailedMessage, { detail });
+      }
     } catch (_err) {
-      errMsg = intl.formatMessage(messages.errorPasteClipboardMessage);
+      // ignore
     }
-    return errMsg;
+    return intl.formatMessage(defaultMessage);
   };
 
   const isBlockTypeEnabled = (blockType: string) => getConfig().LIBRARY_SUPPORTED_BLOCKS.includes(blockType);
@@ -178,7 +185,11 @@ const AddContentContainer = () => {
       linkComponent(data.id);
       showToast(intl.formatMessage(messages.successPasteClipboardMessage));
     }).catch((error) => {
-      showToast(parsePasteErrorMsg(error));
+      showToast(parseErrorMsg(
+        error,
+        messages.errorPasteClipboardMessageWithDetail,
+        messages.errorPasteClipboardMessage,
+      ));
     });
   };
 
@@ -196,8 +207,12 @@ const AddContentContainer = () => {
         // We can't start editing this right away so just show a toast message:
         showToast(intl.formatMessage(messages.successCreateMessage));
       }
-    }).catch(() => {
-      showToast(intl.formatMessage(messages.errorCreateMessage));
+    }).catch((error) => {
+      showToast(parseErrorMsg(
+        error,
+        messages.errorCreateMessageWithDetail,
+        messages.errorCreateMessage,
+      ));
     });
   };
 
diff --git a/src/library-authoring/add-content/messages.ts b/src/library-authoring/add-content/messages.ts
index b1be04e89..a720c12ce 100644
--- a/src/library-authoring/add-content/messages.ts
+++ b/src/library-authoring/add-content/messages.ts
@@ -64,7 +64,15 @@ const messages = defineMessages({
   errorCreateMessage: {
     id: 'course-authoring.library-authoring.add-content.error.text',
     defaultMessage: 'There was an error creating the content.',
-    description: 'Message when creation of content in library is on error',
+    description: 'Message when creation of content in library is on error.',
+  },
+  errorCreateMessageWithDetail: {
+    id: 'course-authoring.library-authoring.add-content.error.text-detail',
+    defaultMessage: 'There was an error creating the content: {detail}',
+    description: (
+      'Message when creation of content in library is on error.'
+      + ' The {detail} text provides more information about the error.'
+    ),
   },
   linkingComponentMessage: {
     id: 'course-authoring.library-authoring.linking-collection-content.progress.text',
@@ -96,6 +104,14 @@ const messages = defineMessages({
     defaultMessage: 'There was an error pasting the content.',
     description: 'Message when pasting clipboard in library errors',
   },
+  errorPasteClipboardMessageWithDetail: {
+    id: 'course-authoring.library-authoring.paste-clipboard.error.text-detail',
+    defaultMessage: 'There was an error pasting the content: {detail}',
+    description: (
+      'Message when pasting clipboard in library errors.'
+      + ' The {detail} text provides more information about the error.'
+    ),
+  },
   pastingClipboardMessage: {
     id: 'course-authoring.library-authoring.paste-clipboard.loading.text',
     defaultMessage: 'Pasting content from clipboard...',