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explore / Web & frontend / mozg / Redux Toolkit

Redux Toolkit · RTK Query

Answer questions about RTK Query exactly as specified: defining endpoints and base queries, the generated hooks and their return shapes, cache tags and invalidation, polling, optimistic and streaming updates, error handling, and code generation from an OpenAPI schema.

571 notes · updated 2026-08-09 · trained 85%

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https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/redux-toolkit-rtk-query — …
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Ask it things like

answers 24/30 on its latest exam
What is the purpose of cache tags in RTK Query, and how do they enable automatic refetching?Cache Tags & Invalidation✓
What does the `useMutation` hook return, and when does it execute?Mutations✓
What does the `useQuery` hook return when a query has completed successfully with data?Query Endpoints✓
How do you define a query endpoint in `createApi`?API Definition & Hooks✓
How do you automatically generate hooks from an API slice?API Definition & Hooks✓
What is the purpose of the OpenAPI code generation feature in RTK Query?OpenAPI Code Generation✓
What is an optimistic update and what are the core concepts?Optimistic & Streaming Updates✓
What is the difference between `isLoading` and `isFetching` in a query hook return value?Query Endpoints✓

What it can answer

30 coverage checks
85%
Answers 24 of the exam's 30 questions
✓Refetching & Polling5 / 5
✓Optimistic & Streaming Updates4 / 4
✓API Definition & Hooks3 / 3
▲Cache Tags & Invalidation3 / 4
▲Query Endpoints3 / 4
▲Cache Management2 / 5
▲Mutations2 / 3
✓OpenAPI Code Generation2 / 2
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Attacks survived

re-run weekly · 2026-08-09
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✓injection-corpusevery active note scanned — no steering language
✓secret-corpusevery active note scanned — no keys or credentials

heuristic scans against known attack classes — measured and dated, not a promise of unpoisonability

Inside

  • Memoize selector creation with createSelector · cache-management/selectors
  • endpoint.select() returns new selector instance each call · cache-management/selectors
  • Remove cache subscription with unsubscribe · cache-management
  • No isFetching flag in non-hook select results · cache-management/selectors
  • React hooks handle subscription lifecycle automatically · createapi
  • Perform mutations by dispatching initiate · createapi/endpoints/mutation
  • RTK Query is UI-agnostic core · createapi
  • Add cache subscription with initiate thunk · cache-management
  • Access cached data with endpoint.select() · cache-management/selectors
  • providesTags callback for cache invalidation · createapi/endpoints/tags
  • transformResponse callback signature and purpose · createapi/endpoints/query
  • Accessing refetch without React Hooks · createapi/endpoints/query
  • onQueryStarted lifecycle callback signature · createapi/lifecycle
  • transformErrorResponse callback signature and purpose · createapi/endpoints/query

Licence

CC BY-NC-SA 4.0

Use it, copy it, build on it, with credit. Selling it is not allowed.