This TypeScript compilation error occurs when upgrading RTK Query to version 2.4.0 or later, where internal type definitions for tag descriptions cause compatibility issues even when not using tags in your API definitions.
The error indicates a type mismatch in RTK Query's internal tag handling system. When you upgrade to RTK Query 2.4.0+, the TypeScript definitions for tag descriptions become stricter, and the internal code that processes tags may receive undefined or null values where it expects defined TagDescription objects. This happens even if you're not explicitly using tags in your API slice definition.
Ensure your createApi call explicitly defines tagTypes as an empty array with const assertion. This helps TypeScript infer the correct types:
import { createApi } from '@reduxjs/toolkit/query/react';
export const api = createApi({
reducerPath: 'api',
baseQuery: fetchBaseQuery({ baseUrl: '/api' }),
tagTypes: [] as const, // Explicit empty array with const assertion
endpoints: () => ({})
});If you have endpoints with providesTags or invalidatesTags, ensure they return proper tag descriptions and not undefined:
endpoints: (builder) => ({
getItems: builder.query({
query: () => '/items',
providesTags: (result) =>
result
? [...result.map(({ id }) => ({ type: 'Item' as const, id }))]
: [{ type: 'Item' as const, id: 'LIST' }]
})
})Make sure the providesTags function always returns an array of tag descriptions, never undefined.
If you need immediate compilation while investigating, you can temporarily revert to RTK Query 2.3.0:
npm install @reduxjs/[email protected]Note: RTK Query 2.3.0 is bundled with @reduxjs/toolkit 1.9.7. This is a temporary workaround while you update your code to be compatible with 2.4.0+.
Ensure your TypeScript configuration has appropriate strictness settings. The error might be more visible with strictNullChecks enabled:
{
"compilerOptions": {
"strict": true,
"strictNullChecks": true
}
}These settings help catch potential runtime errors at compile time.
Visit the RTK Query GitHub repository to check for reported issues and potential fixes:
- GitHub Issue: https://github.com/reduxjs/redux-toolkit/issues/4807
- Look for any patches or workarounds suggested by maintainers
- Consider updating to the latest version which may have fixes
The issue was reported and may be addressed in subsequent releases.
This error highlights the importance of proper TypeScript configuration when using libraries with complex type systems. RTK Query uses advanced TypeScript features for type safety, and version upgrades may expose previously hidden type inconsistencies. When working with tagged caching systems, ensure all code paths return consistent tag descriptions. The const assertion (as const) is particularly important for TypeScript to infer literal types correctly in RTK Query tag definitions.
React Hook useCallback has a missing dependency: 'variable'. Either include it or remove the dependency array react-hooks/exhaustive-deps
React Hook useCallback has a missing dependency
Cannot use private fields in class components without TS support
Cannot use private fields in class components without TS support
Cannot destructure property 'xxx' of 'undefined'
Cannot destructure property of undefined when accessing props
useNavigate() may be used only in the context of a <Router> component.
useNavigate() may be used only in the context of a Router component
Cannot find module or its corresponding type declarations
How to fix "Cannot find module or type declarations" in Vite