vercel/ai · error · InvalidArgumentError

Model '${this.modelId}' only supports streaming transcriptio

Error message

Model '${this.modelId}' only supports streaming transcription. Use experimental_streamTranscribe, or a unary model such as 'gemini-3.5-transcribe'.

What it means

Error "Model '${this.modelId}' only supports streaming transcription. Use experimental_streamTranscribe, or a unary model such as 'gemini-3.5-transcribe'." thrown in vercel/ai.

Source

Thrown at packages/google-vertex/src/gemini-transcription/google-vertex-gemini-transcription-model.ts:159

  ): Promise<GoogleVertexTranscriptionModelGeminiOptions | undefined> {
    // The Vertex provider exposes options under `googleVertex`/`vertex`;
    // accept `google` as a cross-namespace fallback (e.g. via the AI Gateway).
    for (const provider of ['googleVertex', 'vertex', 'google'] as const) {
      const parsed = await parseProviderOptions({
        provider,
        providerOptions,
        schema: googleVertexGeminiTranscriptionModelOptions,
      });
      if (parsed != null) return parsed;
    }
    return undefined;
  }

  async doGenerate(
    options: Parameters<TranscriptionModelV4['doGenerate']>[0],
  ): Promise<Awaited<ReturnType<TranscriptionModelV4['doGenerate']>>> {
    if (isLiveTranscriptionModelId(this.modelId)) {
      throw new InvalidArgumentError({
        argument: 'modelId',
        message:
          `Model '${this.modelId}' only supports streaming transcription. ` +
          `Use experimental_streamTranscribe, or a unary model such as 'gemini-3.5-transcribe'.`,
      });
    }

    const currentDate = this.config._internal?.currentDate?.() ?? new Date();
    const warnings: SharedV4Warning[] = [];
    const googleOptions = await this.parseOptions(options.providerOptions);
    const audioTranscriptionConfig =
      buildAudioTranscriptionConfig(googleOptions);

    const requestBody = {
      contents: [
        {
          role: 'user',
          parts: [

View on GitHub (pinned to 69428b1f8b)

When it happens

Trigger: Thrown at packages/google-vertex/src/gemini-transcription/google-vertex-gemini-transcription-model.ts:159 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of vercel/ai@69428b1f8b (2026-08-30). Data as JSON: /api/errors/a1bbaead83ab6be6. Report an issue: GitHub.