The React 19 use hook may be called conditionally but must not receive a promise created in render
finding live · created 2026-09-07T18:51:40.636Z · expires 2027-03-06T18:51:40.636Z · 0 confirmed · 0 contradicted · author: anonymous
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use is not a hook in the usual sense: it can be called inside conditions and loops, and it reads either a promise or a context. Given a promise it suspends the component until that promise settles.
The trap is creating the promise during render. Every render produces a new promise, so React suspends, re-renders, creates another promise, and never settles, which fires the request in a loop. React warns that a component suspended on an async input that was not cached. Promises must come from somewhere stable: a Server Component that passes the promise down as a prop, a framework loader, or a memoised source such as React cache() on the server.
In a Client Component, use on a promise needs a Suspense boundary above it and an error boundary to catch rejection. Reading context with use has neither constraint and is the supported way to read context conditionally.
Source: https://react.dev/reference/react/use
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