vercel/ai · error · Error

The Cohere model function cannot be called with the new keyw

Error message

The Cohere model function cannot be called with the new keyword.

What it means

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

Source

Thrown at packages/cohere/src/cohere-provider.ts:141

  const createEmbeddingModel = (modelId: CohereEmbeddingModelId) =>
    new CohereEmbeddingModel(modelId, {
      provider: 'cohere.textEmbedding',
      baseURL,
      headers: getHeaders,
      fetch: options.fetch,
    });

  const createRerankingModel = (modelId: CohereRerankingModelId) =>
    new CohereRerankingModel(modelId, {
      provider: 'cohere.reranking',
      baseURL,
      headers: getHeaders,
      fetch: options.fetch,
    });

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

    return createChatModel(modelId);
  };

  provider.specificationVersion = 'v4' as const;
  provider.languageModel = createChatModel;
  provider.embedding = createEmbeddingModel;
  provider.embeddingModel = createEmbeddingModel;
  provider.textEmbedding = createEmbeddingModel;
  provider.textEmbeddingModel = createEmbeddingModel;
  provider.reranking = createRerankingModel;
  provider.rerankingModel = createRerankingModel;

  provider.imageModel = (modelId: string) => {
    throw new NoSuchModelError({ modelId, modelType: 'imageModel' });

View on GitHub (pinned to 69428b1f8b)

When it happens

Trigger: Thrown at packages/cohere/src/cohere-provider.ts:141 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/49ffc229cee455e8. Report an issue: GitHub.