new·The score now tells you which way it movedA brain's exam only ever grows: its own material writes questions, and so does every question a real caller asked and did not get answered. The score is a percentage over that growing set, so a brain that learned more could post a smaller number — and this week three did. One of them answered two MORE questions than the week before and showed eighteen points less. Printed as a single percentage, that reads as decline to a reader and as punishment to anyone who contributes material.all news →
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TanStack Query

Answer questions about TanStack Query v5 for React as documented today: queries, mutations and their exact option names, query keys and invalidation, caching with staleTime and gcTime, suspense and streaming, infinite and paginated queries, optimistic updates, SSR and hydration — including which v4 names were removed and what replaced them.

991 notes across 3 brains · updated 2026-08-09 · trained 96%

since last sitting: +3 newly passed — this brain is learning · the verified changelog →

use this brain
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$ claude mcp add --transport http mozg \
https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/tanstack-query — …
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Ask it things like

answers 36/37 on its latest exam · anti-bluff 1/2
What are the default staleTime and gcTime values?Caching and invalidation✓
What does invalidateQueries do exactly?Caching and invalidation✓
What is initialPageParam and why is it required in useInfiniteQuery?Infinite and paginated queries✓
What is the return type of useMutation?Mutations and state✓
How do I perform an optimistic update with onMutate?Optimistic updates✓
When should I use keepPreviousData in useQuery?Query hooks and options✓
What is the difference between useQuery and useSuspenseQuery return values?Query hooks and options✓
What is the correct pattern for using QueryClientProvider?Setup and configuration✓

What is inside

asking this brain searches all 2
TanStack Query · ReactAnswer questions about using TanStack Query in React: the guides for queries, mutations, invalidation, caching behaviour, suspense, infinite queries, optimistic updates, SSR and hydration, testing, and the migration from v4.833 notes89%TanStack Query · ReferenceAnswer questions about the TanStack Query API exactly as specified: every hook and its options with types and defaults, QueryClient methods, and the ESLint rules with what each catches.158 notes81%

What it can answer

37 coverage checks
96%
Answers 37 of the exam's 39 questionsIt answers 37 questions, 3 more than last time.
✓Caching and invalidation4 / 4
✓Mutations and state4 / 4
✓Query hooks and options4 / 4
✓SSR and hydration4 / 4
✓v5 migration from v44 / 4
✓Infinite and paginated queries3 / 3
✓Optimistic updates3 / 3
✓Suspense and streaming3 / 3
✓TypeScript integration3 / 3
▲Network modes and online detection2 / 3
✓Setup and configuration2 / 2
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Attacks survived

re-run weekly · 2026-08-10
✓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

    Licence

    CC BY-NC-SA 4.0

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