apify/crawlee · error · Error

The `response` property is not available. This might mean th

Error message

The `response` property is not available. This might mean that you're trying to access it before navigation or that navigation resulted in `null` (this should only happen with `about:` URLs)

What it means

In the pre-navigation phase of the crawling context, the `response` property has no value yet. Accessing it before navigation completes (or when navigation yields null, e.g. for `about:` URLs) throws this error rather than returning undefined, to surface lifecycle mistakes clearly.

Source

Thrown at packages/browser-crawler/src/internals/browser-crawler.ts:606

            id: crawlingContext.id,
            session: crawlingContext.session,
        });
        tryCancel();

        const addRequests = crawlingContext.addRequests;

        const extractLinks = async (options?: ExtractLinksOptions): Promise<string[]> => {
            return extractUrlsFromPage(
                page as any,
                options?.selector ?? 'a',
                options?.baseUrl ?? crawlingContext.request.loadedUrl ?? crawlingContext.request.url,
            );
        };

        return {
            page,
            get response(): Response {
                throw new Error(
                    "The `response` property is not available. This might mean that you're trying to access it before navigation or that navigation resulted in `null` (this should only happen with `about:` URLs)",
                );
            },
            get gotoOptions(): Dictionary {
                throw new Error('The `gotoOptions` property is not available until `prepareNavigation` runs.');
            },
            extractLinks,
            enqueueLinks: async (options: EnqueueLinksOptions = {}) => {
                const baseUrl = resolveBaseUrlForEnqueueLinksFiltering({
                    enqueueStrategy: options.strategy,
                    finalRequestUrl: crawlingContext.request.loadedUrl,
                    originalRequestUrl: crawlingContext.request.url,
                    userProvidedBaseUrl: options.baseUrl,
                });

                const urls = await extractLinks(options);

                return addRequests(urls, {

View on GitHub (pinned to dbe57fb09c)

Solutions

1. Access context.response only in the request handler after navigation has run
2. Add a guard: check that response exists before using it
3. For about:/null responses, use the page directly instead of the response object

Example fix

// before
async requestHandler(ctx) { ... } // but middleware before navigation does: ctx.response.status
// after
// in post-navigation code only:
if (ctx.response) { const status = ctx.response.status; }

const status = ctx.response ? ctx.response.status : undefined;

function hasResponse<T extends { response?: Response | undefined }>(ctx: T): ctx is T & { response: Response } {
    try { void ctx.response; return true; } catch { return false; }
}

let response: Response | undefined;
try { response = ctx.response; } catch { /* accessed before navigation or about: URL */ }

When it happens

Trigger: Reading context.response inside a hook/middleware that runs before navigation (e.g. context preparation, pre-navigation hooks), or after navigation to an `about:` URL where response is null.

Common situations: Custom middlewares added before the navigation middleware reading response; request handlers relying on response for about:blank navigation; accessing response in prepareRequest-like callbacks.

Related errors

• The `gotoOptions` property is not available until `prepareNa
• Navigation timed out after ${this.#navigationTimeoutMillis /
• The `request.loadedUrl` property is not available - `skipNav
• The `response` property is not available - `skipNavigation`
• This crawler instance is already running, you can add more r

AI-assisted analysis of apify/crawlee@dbe57fb09c (2026-08-30). Data as JSON: /api/errors/f0543d0367d0ea79. Report an issue: GitHub.