Vercel AI SDK - OpenAI Provider

The OpenAI provider for the Vercel AI SDK contains language model support for the OpenAI chat and completion APIs. It creates language model objects that can be used with the generateText, streamText, generateObject, and streamObject AI functions.

Setup

The OpenAI provider is available in the @ai-sdk/openai module. You can install it with

npm i @ai-sdk/openai

Provider Instance

You can import the default provider instance openai from @ai-sdk/openai:

import { openai } from '@ai-sdk/openai';

If you need a customized setup, you can import createOpenAI from @ai-sdk/openai and create a provider instance with your settings:

import { createOpenAI } from '@ai-sdk/openai';

const openai = createOpenAI({
  // custom settings
});

You can use the following optional settings to customize the OpenAI provider instance:

• baseURL string

  Use a different URL prefix for API calls, e.g. to use proxy servers. The default prefix is https://api.openai.com/v1.

• apiKey string

  API key that is being send using the Authorization header. It defaults to the OPENAI_API_KEY environment variable.

• organization string

  OpenAI Organization.

• project string

  OpenAI project.

• headers Record<string,string>

  Custom headers to include in the requests.

Models

The OpenAI provider instance is a function that you can invoke to create a model:

const model = openai('gpt-3.5-turbo');

It automatically selects the correct API based on the model id. You can also pass additional settings in the second argument:

const model = openai('gpt-3.5-turbo', {
  // additional settings
});

The available options depend on the API that's automatically chosen for the model (see below). If you want to explicitly select a specific model API, you can use .chat or .completion.

Chat Models

You can create models that call the OpenAI chat API using the .chat() factory method. The first argument is the model id, e.g. gpt-4. The OpenAI chat models support tool calls and some have multi-modal capabilities.

const model = openai.chat('gpt-3.5-turbo');

OpenAI chat models support also some model specific settings that are not part of the standard call settings. You can pass them as an options argument:

const model = openai.chat('gpt-3.5-turbo', {
  logitBias: {
    // optional likelihood for specific tokens
    '50256': -100,
  },
  user: 'test-user', // optional unique user identifier
});

The following optional settings are available for OpenAI chat models:

• logitBias Record<number, number>

  Modifies the likelihood of specified tokens appearing in the completion.

  Accepts a JSON object that maps tokens (specified by their token ID in the GPT tokenizer) to an associated bias value from -100 to 100. You can use this tokenizer tool to convert text to token IDs. Mathematically, the bias is added to the logits generated by the model prior to sampling. The exact effect will vary per model, but values between -1 and 1 should decrease or increase likelihood of selection; values like -100 or 100 should result in a ban or exclusive selection of the relevant token.

  As an example, you can pass {"50256": -100} to prevent the <|endoftext|> token from being generated.

• logProbs boolean | number

  Return the log probabilities of the tokens. Including logprobs will increase the response size and can slow down response times. However, it can be useful to better understand how the model is behaving.

  Setting to true will return the log probabilities of the tokens that were generated.

  Setting to a number will return the log probabilities of the top n tokens that were generated.

• user string

  A unique identifier representing your end-user, which can help OpenAI to monitor and detect abuse. Learn more.

Completion Models

You can create models that call the OpenAI completions API using the .completion() factory method. The first argument is the model id. Currently only gpt-3.5-turbo-instruct is supported.

const model = openai.completion('gpt-3.5-turbo-instruct');

OpenAI completion models support also some model specific settings that are not part of the standard call settings. You can pass them as an options argument:

const model = openai.completion('gpt-3.5-turbo-instruct', {
  echo: true, // optional, echo the prompt in addition to the completion
  logitBias: {
    // optional likelihood for specific tokens
    '50256': -100,
  },
  suffix: 'some text', // optional suffix that comes after a completion of inserted text
  user: 'test-user', // optional unique user identifier
});

The following optional settings are available for OpenAI completion models:

• echo: boolean

  Echo back the prompt in addition to the completion.

• logitBias Record<number, number>

  Modifies the likelihood of specified tokens appearing in the completion.

  Accepts a JSON object that maps tokens (specified by their token ID in the GPT tokenizer) to an associated bias value from -100 to 100. You can use this tokenizer tool to convert text to token IDs. Mathematically, the bias is added to the logits generated by the model prior to sampling. The exact effect will vary per model, but values between -1 and 1 should decrease or increase likelihood of selection; values like -100 or 100 should result in a ban or exclusive selection of the relevant token.

  As an example, you can pass {"50256": -100} to prevent the <|endoftext|> token from being generated.

• logProbs boolean | number

  Return the log probabilities of the tokens. Including logprobs will increase the response size and can slow down response times. However, it can be useful to better understand how the model is behaving.

  Setting to true will return the log probabilities of the tokens that were generated.

  Setting to a number will return the log probabilities of the top n tokens that were generated.

• suffix string

  The suffix that comes after a completion of inserted text.

• user string

  A unique identifier representing your end-user, which can help OpenAI to monitor and detect abuse. Learn more.