Parameters for the completions.create operation.

interface CreateCompletionsParams {
    bestOf?: number;
    cache?: CompletionsCache;
    echo?: boolean;
    frequencyPenalty?: number;
    headers?: OutgoingHttpHeaders;
    logitBias?: JSONObject;
    logprobs?: number;
    maxTokens?: number;
    metadata?: JSONObject;
    model: string;
    n?: number;
    presencePenalty?: number;
    prompt: string;
    router?: ModelRouter;
    seed?: number;
    signal?: AbortSignal;
    stop?: string[];
    stream?: boolean;
    streamOptions?: StreamOptions;
    suffix?: string;
    temperature?: number;
    topP?: number;
    user?: string;
}

Hierarchy (view full)

Properties

bestOf?: number

Generates best_of number of completions server-side and returns the "best" (the one with the highest log probability per token). Results cannot be streamed. When used with n, best_of controls the number of candidate completions and n specifies how many to return – best_of must be greater than n.

Note: Because this parameter generates many completions, it can quickly consume your token quota. Use carefully and ensure that you have reasonable settings for max_tokens and stop.

Caching configuration for the request. Cache is only supported for non-streaming requests.

echo?: boolean

Echo back the prompt in addition to the completion.

frequencyPenalty?: number

A number between -2.0 and 2.0. Positive values penalize new tokens based on their existing frequency in the text so far, decreasing the model's likelihood to repeat the same line verbatim.

headers?: OutgoingHttpHeaders
logitBias?: JSONObject

Used to modify 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 and
  • 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?: number

The number of most likely output tokens to include the log probabilities of, as well the chosen tokens. For example, if logprobs is 5, the API will return a list of the 5 most likely tokens. The API will always return the logprob of the sampled token, so there may be up to logprobs+1 elements in the response. The maximum value for logprobs is 5.

maxTokens?: number

The maximum number of tokens that can be generated in the completion. The token count of your prompt plus max_tokens cannot exceed the model's context length.

metadata?: JSONObject

Contains developer-defined tags and values used for filtering completions.

model: string

Model is the ID of the model to use.

n?: number

Specifies how many completions to generate for each prompt.

Note: Because this parameter generates many completions, it can quickly consume your token quota. Use carefully and ensure that you have reasonable settings for max_tokens and stop.

presencePenalty?: number

A number between -2.0 and 2.0. Positive values penalize new tokens based on whether they appear in the text so far, increasing the model's likelihood to talk about new topics.

prompt: string

Prompt(s) to generate completions for, encoded as a string, array of strings, array of tokens, or array of token arrays.

Note: <|endoftext|> is the document separator that the model sees during training, so if a prompt is not specified the model will generate as if from the beginning of a new document.

router?: ModelRouter

Router is the model routing configuration for the request.

seed?: number

The seed for the model request. If specified, OpenAI's system will make a best effort to sample deterministically, such that repeated requests with the same seed and parameters should return the same result.

Determinism is not guaranteed, and you should refer to the system_fingerprint response parameter to monitor changes in the backend.

signal?: AbortSignal
stop?: string[]

Specifies up to 4 sequences where the API will stop generating further tokens.

stream?: boolean

Indicates whether to stream back partial progress. If set, tokens will be sent as data-only server-sent events as they become available, with the stream terminated by a data: [DONE] message.

streamOptions?: StreamOptions

Options for streaming response. Only set this when you set stream to true.

suffix?: string

Text that comes after a completion of inserted text. On OpenAI, this parameter is only supported for gpt-3.5-turbo-instruct.

temperature?: number

Specifies what temperature to use for sample, between 0 and 2. Higher values like 0.8 will make the output more random, while lower values like 0.2 will make it more focused and deterministic.

Note: OpenAI generally recommends altering this or top_p but not both.

topP?: number

An alternative to sampling with temperature, called nucleus sampling, where the model considers the results of the tokens with top_p probability mass. So 0.1 means only the tokens comprising the top 10% probability mass are considered.

Note: OpenAI generally recommends altering this or temperature but not both.

user?: string

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