sveltejs/kit · error · HandledHttpError

${prerendered.error}

Error message

${prerendered.error}

What it means

During prerendering, remote functions first look up a prerendered response cache entry. If that entry is of type 'error', the stored error is re-thrown as a HandledHttpError with the prerendered error's original message, reproducing the failure that was captured when the page was prerendered.

Source

Thrown at packages/kit/src/runtime/app/server/remote/prerender.js:116

				/** @type {RemoteFunctionResponse | undefined} */
				let prerendered;

				try {
					// TODO adapters can provide prerendered data more efficiently than
					// fetching from the public internet
					// `request.url` rather than `event.url`, which throws inside queries
					const response = await fetch(new URL(url, event.request.url).href);

					if (response.ok) {
						prerendered = /** @type {RemoteFunctionResponse} */ (await response.json());
					}
				} catch {
					// not available prerendered, fallback to normal function
				}

				if (prerendered) {
					if (prerendered.type === 'error') {
						throw new HandledHttpError(prerendered.error);
					}

					return parse(prerendered.data)._;
				}
			}

			// during a prerender run, the same function might be invoked while rendering
			// multiple pages — share the result across the entire run
			if (state.prerendering?.remote_responses.has(url)) {
				return /** @type {Promise<any>} */ (state.prerendering.remote_responses.get(url));
			}

			const promise = run_remote_function(
				event,
				{ ...state, is_in_remote_prerender: true },
				false,
				() => validate(arg),
				fn

View on GitHub (pinned to 03f1687fe6)

Solutions

1. Fix the root error the remote function threw during prerendering (check build logs for the original failure)
2. Delete the .svelte-kit/build output and re-prerender so the error entry is regenerated
3. Guard the remote call with a fallback so it does not fail during prerender
4. Ensure required env vars/secrets are available at build time

Example fix

// before: prerendered page captured a failing query
export const load = async () => ({ posts: await getPosts() }); // fails at build if API down
// after
import { prerender } from '$app/server';
export const load = async () => {
  try {
    return { posts: await getPosts() };
  } catch {
    return { posts: [] };
  }
};

null

null

try {
  return await myQuery(arg);
} catch (e) {
  return fallbackValue; // don't let prerendered error entries propagate
}

When it happens

Trigger: A remote function is invoked during runtime (or prerender fallback) and finds a prerendered cache entry whose type is 'error' — i.e. the remote call failed when the page was originally prerendered and that failure was serialized into the prerender manifest.

Common situations: Deploying prerendered pages whose remote query/command failed at build time (expired tokens, missing env vars at build); stale .svelte-kit output after an API change; a prerendered page snapshotting an intermittent backend failure.

Related errors

• Cannot call query '${__.name}' while prerendering, as preren
• Cannot call query.batch '${__.name}' while prerendering, as
• Cannot call '${__.name}.withOverride()' on the server
• Cannot access cloudflare:workers in a prerenderable route
• Could not get the request store.

AI-assisted analysis of sveltejs/kit@03f1687fe6 (2026-09-02). Data as JSON: /api/errors/16e779c4c0371ad2. Report an issue: GitHub.