validation added to NumericalInput to just accept numerical values on block creation form

src/editors/containers/ProblemEditor/components/EditProblemView/AnswerWidget/AnswerOption.jsx

@@ -19,6 +19,7 @@ import * as hooks from './hooks';
 import { ProblemTypeKeys } from '../../../../../data/constants/problem';
 import ExpandableTextArea from '../../../../../sharedComponents/ExpandableTextArea';
 import { answerRangeFormatRegex } from '../../../data/OLXParser';
+import { useValidateInputBlock } from '../../../data/apiHooks';
 
 const AnswerOption = ({
   answer,
@@ -32,7 +33,6 @@ const AnswerOption = ({
   const isLibrary = useSelector(selectors.app.isLibrary);
   const learningContextId = useSelector(selectors.app.learningContextId);
   const blockId = useSelector(selectors.app.blockId);
-
   const removeAnswer = hooks.removeAnswer({ answer, dispatch });
   const setAnswer = hooks.setAnswer({ answer, hasSingleAnswer, dispatch });
   const setAnswerTitle = hooks.setAnswerTitle({
@@ -44,6 +44,7 @@ const AnswerOption = ({
   const setSelectedFeedback = hooks.setSelectedFeedback({ answer, hasSingleAnswer, dispatch });
   const setUnselectedFeedback = hooks.setUnselectedFeedback({ answer, hasSingleAnswer, dispatch });
   const { isFeedbackVisible, toggleFeedback } = hooks.useFeedback(answer);
+  const { data = { isValid: true }, mutate } = useValidateInputBlock();
 
   const staticRootUrl = isLibrary
     ? `${getConfig().STUDIO_BASE_URL}/library_assets/blocks/${blockId}/`
@@ -69,17 +70,31 @@ const AnswerOption = ({
         />
       );
     }
+
     if (problemType !== ProblemTypeKeys.NUMERIC || !answer.isAnswerRange) {
       return (
-        <Form.Control
-          as="textarea"
-          className="answer-option-textarea text-gray-500 small"
-          autoResize
-          rows={1}
-          value={answer.title}
-          onChange={setAnswerTitle}
-          placeholder={intl.formatMessage(messages.answerTextboxPlaceholder)}
-        />
+        <Form.Group isInvalid={!data?.isValid ?? true}>
+          <Form.Control
+            as="textarea"
+            className="answer-option-textarea text-gray-500 small"
+            autoResize
+            rows={1}
+            value={answer.title}
+            onChange={(e) => {
+              setAnswerTitle(e);
+              if (problemType === ProblemTypeKeys.NUMERIC) {
+                mutate(e.target.value);
+              }
+            }}
+            placeholder={intl.formatMessage(messages.answerTextboxPlaceholder)}
+
+          />
+          {(!data?.isValid ?? true) && (
+          <Form.Control.Feedback type="invalid">
+            <FormattedMessage {...messages.answerNumericErrorText} />
+          </Form.Control.Feedback>
+          )}
+        </Form.Group>
       );
     }
     // Return Answer Range View

src/editors/containers/ProblemEditor/components/EditProblemView/AnswerWidget/AnswerOption.test.tsx

@@ -3,6 +3,7 @@ import { render, screen, initializeMocks } from '@src/testUtils';
 import { selectors } from '@src/editors/data/redux';
 import AnswerOption from './AnswerOption';
 import * as hooks from './hooks';
+import * as reactQueryHooks from '../../../data/apiHooks';
 
 const { problem } = selectors;
 
@@ -101,4 +102,16 @@ describe('AnswerOption', () => {
     expect(screen.getByText(answerRange.title)).toBeInTheDocument();
     expect(screen.getByRole('textbox')).toBeInTheDocument();
   });
+
+  test('shows numeric error feedback when data.isValid is false', () => {
+    // Mock useValidateInputBlock to simulate invalid state
+    // @ts-ignore-next-line
+    jest.spyOn(reactQueryHooks, 'useValidateInputBlock').mockReturnValue({ data: { isValid: false } });
+    jest.spyOn(problem, 'problemType').mockReturnValue('numericalresponse');
+    const myProps = { ...props, answer: { ...answerWithOnlyFeedback, isAnswerRange: false } };
+    render(<AnswerOption {...myProps} />);
+    expect(
+      screen.getByText('Error: This input type only supports numeric answers. Did you mean to make a Text input or Math expression input problem?'),
+    ).toBeInTheDocument();
+  });
 });

src/editors/containers/ProblemEditor/components/EditProblemView/AnswerWidget/messages.js

@@ -82,6 +82,11 @@ const messages = defineMessages({
     defaultMessage: 'Error: Invalid range format. Use brackets or parentheses with values separated by a comma.',
     description: 'Error text describing wrong format of answer ranges',
   },
+  answerNumericErrorText: {
+    id: 'authoring.answerwidget.answer.answerNumericErrorText',
+    defaultMessage: 'Error: This input type only supports numeric answers. Did you mean to make a Text input or Math expression input problem?',
+    description: 'Error message when user provides wrong format',
+  },
 });
 
 export default messages;

src/editors/containers/ProblemEditor/data/apiHooks.test.tsx

@@ -0,0 +1,69 @@
+import { renderHook, waitFor } from '@testing-library/react';
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import { camelCaseObject, getConfig } from '@edx/frontend-platform';
+import api from '@src/editors/data/services/cms/api';
+import { useValidateInputBlock } from './apiHooks';
+
+// Mock external dependencies
+jest.mock('@edx/frontend-platform');
+jest.mock('@src/editors/data/services/cms/api', () => ({
+  validateBlockNumericInput: jest.fn(),
+}));
+
+const mockedCamelCaseObject = jest.mocked(camelCaseObject);
+const mockedGetConfig = jest.mocked(getConfig);
+const mockedValidateBlockNumericInput = jest.mocked(api.validateBlockNumericInput);
+
+// Test wrapper component
+const createWrapper = () => {
+  const queryClient = new QueryClient({
+    defaultOptions: {
+      queries: { retry: false },
+      mutations: { retry: false },
+    },
+  });
+
+  const wrapper = ({ children }) => (
+    <QueryClientProvider client={queryClient}>
+      {children}
+    </QueryClientProvider>
+  );
+  return wrapper;
+};
+
+describe('useValidateInputBlock', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockedGetConfig.mockReturnValue({
+      STUDIO_BASE_URL: 'http://studio.local.openedx.io:8001',
+    });
+  });
+
+  test('should return camelCase data on successful API call', async () => {
+    const mockResponse = {
+      data: { is_valid: true, result: 'success' },
+    } as any;
+    const mockCamelCaseResult = { isValid: true, result: 'success' };
+
+    mockedValidateBlockNumericInput.mockResolvedValue(Promise.resolve(mockResponse));
+    mockedCamelCaseObject.mockReturnValue(mockCamelCaseResult);
+
+    const { result } = renderHook(() => useValidateInputBlock(), {
+      wrapper: createWrapper(),
+    });
+
+    const testFormula = 'x + 1';
+    result.current.mutate(testFormula);
+
+    await waitFor(() => {
+      expect(result.current.isSuccess).toBe(true);
+    });
+
+    expect(mockedValidateBlockNumericInput).toHaveBeenCalledWith({
+      studioEndpointUrl: 'http://studio.local.openedx.io:8001',
+      data: { formula: testFormula },
+    });
+    expect(mockedCamelCaseObject).toHaveBeenCalledWith(mockResponse.data);
+    expect(result.current.data).toEqual({ isValid: true, result: 'success' });
+  });
+});

src/editors/containers/ProblemEditor/data/apiHooks.ts

@@ -0,0 +1,19 @@
+import { useMutation } from '@tanstack/react-query';
+import { camelCaseObject, getConfig } from '@edx/frontend-platform';
+import api from '@src/editors/data/services/cms/api';
+
+const getApiBaseUrl = () => getConfig().STUDIO_BASE_URL;
+
+export const useValidateInputBlock = () => useMutation({
+  mutationFn: async (title : string) => {
+    try {
+      const res = await api.validateBlockNumericInput({ studioEndpointUrl: `${getApiBaseUrl()}`, data: { formula: title } });
+      return camelCaseObject(res.data);
+    } catch (err: any) {
+      return {
+        isValid: false,
+        error: err.response?.data?.error ?? 'Unknown error',
+      };
+    }
+  },
+});

src/editors/data/services/cms/api.ts

@@ -390,6 +390,13 @@ export const apiMethods = {
   }) => get(
     urls.handlerUrl({ studioEndpointUrl, blockId, handlerName }),
   ),
+  validateBlockNumericInput: ({
+    studioEndpointUrl,
+    data,
+  }) => post(
+    urls.validateNumericInputUrl({ studioEndpointUrl }),
+    data,
+  ),
 };
 
 export default apiMethods;

src/editors/data/services/cms/urls.ts

@@ -123,3 +123,7 @@ export const courseVideos = (({ studioEndpointUrl, learningContextId }) => (
 export const handlerUrl = (({ studioEndpointUrl, blockId, handlerName }) => (
   `${studioEndpointUrl}/api/xblock/v2/xblocks/${blockId}/handler_url/${handlerName}/`
 )) satisfies UrlFunction;
+
+export const validateNumericInputUrl = (({ studioEndpointUrl }) => (
+  `${studioEndpointUrl}/api/contentstore/v2/validate/numerical-input/`
+)) satisfies UrlFunction;