The Gateway Provider model function cannot be called with th

Error message

The Gateway Provider model function cannot be called with the new keyword.

What it means

Error "The Gateway Provider model function cannot be called with the new keyword." thrown in vercel/ai.

Source

Thrown at packages/gateway/src/gateway-provider.ts:502

  const getGenerationInfo = async (params: GatewayGenerationInfoParams) => {
    return new GatewayGenerationInfoFetcher({
      baseURL,
      headers: getHeaders,
      fetch: options.fetch,
    })
      .getGenerationInfo(params)
      .catch(async (error: unknown) => {
        throw await asGatewayError(
          error,
          await parseAuthMethod(await getHeaders()),
        );
      });
  };

  const provider = function (modelId: GatewayModelId) {
    if (new.target) {
      throw new Error(
        'The Gateway Provider model function cannot be called with the new keyword.',
      );
    }

    return createLanguageModel(modelId);
  };

  provider.specificationVersion = 'v4' as const;
  provider.getAvailableModels = getAvailableModels;
  provider.getCredits = getCredits;
  provider.getSpendReport = getSpendReport;
  provider.getGenerationInfo = getGenerationInfo;
  provider.imageModel = (modelId: GatewayImageModelId) => {
    return new GatewayImageModel(modelId, {
      provider: 'gateway',
      baseURL,
      headers: getHeaders,
      fetch: options.fetch,

View on GitHub (pinned to 69428b1f8b)

When it happens

Trigger: Thrown at packages/gateway/src/gateway-provider.ts:502 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/8818dbfbf16c61b5. Report an issue: GitHub.