vercel/ai · info · DOMException

AbortError

AbortError

Error message

Stream aborted

What it means

While piping the streamed response into the accumulated-text parser, the write handler checks abortController.signal.aborted and throws a DOMException('Stream aborted', 'AbortError') to stop processing. This is the deliberate stop mechanism: calling stop() on the structured object aborts the in-flight stream.

Source

Thrown at packages/svelte/src/structured-object.svelte.ts:188

      if (!response.ok) {
        throw new Error(
          (await response.text()) ?? 'Failed to fetch the response.',
        );
      }

      if (response.body == null) {
        throw new Error('The response body is empty.');
      }

      let accumulatedText = '';
      let latestObject: DeepPartial<RESULT> | undefined = undefined;

      await response.body.pipeThrough(new TextDecoderStream()).pipeTo(
        new WritableStream<string>({
          write: async chunk => {
            if (abortController?.signal.aborted) {
              throw new DOMException('Stream aborted', 'AbortError');
            }
            accumulatedText += chunk;

            const { value } = await parsePartialJson(accumulatedText);
            const currentObject = value as DeepPartial<RESULT>;

            if (!isDeepEqualData(latestObject, currentObject)) {
              latestObject = currentObject;

              this.#store.object = currentObject;
            }
          },

          close: async () => {
            this.#store.loading = false;
            this.#abortController = undefined;

            if (this.#options.onFinish != null) {

View on GitHub (pinned to 69428b1f8b)

Solutions

1. Treat AbortError as an intentional stop — catch and ignore it in your error handling.
2. If it fires unexpectedly, check for early unmount or premature stop() calls.
3. Use an AbortSignal timeout that is long enough for generation to complete.
4. Handle the latestObject already accumulated if partial results are useful.

Example fix

// before
startGeneration();
// after
try {
  startGeneration();
} catch (error) {
  if ((error as DOMException)?.name !== 'AbortError') throw error;
}

null

function isAbortError(e) {
  return e instanceof DOMException && e.name === 'AbortError';
}

try {
  await consumeStream();
} catch (error) {
  if (!isAbortError(error)) throw error; // ignore intentional stops
}

When it happens

Trigger: Calling the stop() function returned by useStructuredObject while the response stream is still being consumed; the internal AbortController is aborted and the next write chunk raises this AbortError.

Common situations: User navigates away or cancels generation; component unmount cleanup calls stop(); a timeout aborts the controller mid-stream. Usually expected behavior, not a bug.

Related errors

• Stream aborted
• Transcription request was aborted
• AbortError
• MCP client initialization was aborted
• Failed to fetch the response.

AI-assisted analysis of vercel/ai@69428b1f8b (2026-08-30). Data as JSON: /api/errors/545a220faed41ed4. Report an issue: GitHub.