# CreateChatCompletionRequest
## Fields
| Field | Type | Required | Description | Example |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `Messages` | [][components.ChatCompletionRequestMessage](../../models/components/chatcompletionrequestmessage.md) | :heavy_check_mark: | A list of messages comprising the conversation so far. [Example Python code](https://cookbook.openai.com/examples/how_to_format_inputs_to_chatgpt_models). | |
| `Model` | [components.Model](../../models/components/model.md) | :heavy_check_mark: | ID of the model to use. See the [model endpoint compatibility](/docs/models/model-endpoint-compatibility) table for details on which models work with the Chat API. | gpt-4-turbo |
| `FrequencyPenalty` | **float64* | :heavy_minus_sign: | 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.
[See more information about frequency and presence penalties.](/docs/guides/text-generation/parameter-details)
| |
| `LogitBias` | map[string]*int64* | :heavy_minus_sign: | Modify the likelihood of specified tokens appearing in the completion.
Accepts a JSON object that maps tokens (specified by their token ID in the tokenizer) to an associated bias value from -100 to 100. 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.
| |
| `Logprobs` | **bool* | :heavy_minus_sign: | Whether to return log probabilities of the output tokens or not. If true, returns the log probabilities of each output token returned in the `content` of `message`. | |
| `TopLogprobs` | **int64* | :heavy_minus_sign: | An integer between 0 and 20 specifying the number of most likely tokens to return at each token position, each with an associated log probability. `logprobs` must be set to `true` if this parameter is used. | |
| `MaxTokens` | **int64* | :heavy_minus_sign: | The maximum number of [tokens](/tokenizer) that can be generated in the chat completion.
The total length of input tokens and generated tokens is limited by the model's context length. [Example Python code](https://cookbook.openai.com/examples/how_to_count_tokens_with_tiktoken) for counting tokens.
| |
| `N` | **int64* | :heavy_minus_sign: | How many chat completion choices to generate for each input message. Note that you will be charged based on the number of generated tokens across all of the choices. Keep `n` as `1` to minimize costs. | 1 |
| `PresencePenalty` | **float64* | :heavy_minus_sign: | 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.
[See more information about frequency and presence penalties.](/docs/guides/text-generation/parameter-details)
| |
| `ResponseFormat` | [*components.ResponseFormat](../../models/components/responseformat.md) | :heavy_minus_sign: | An object specifying the format that the model must output. Compatible with [GPT-4 Turbo](/docs/models/gpt-4-and-gpt-4-turbo) and all GPT-3.5 Turbo models newer than `gpt-3.5-turbo-1106`.
Setting to `{ "type": "json_object" }` enables JSON mode, which guarantees the message the model generates is valid JSON.
**Important:** when using JSON mode, you **must** also instruct the model to produce JSON yourself via a system or user message. Without this, the model may generate an unending stream of whitespace until the generation reaches the token limit, resulting in a long-running and seemingly "stuck" request. Also note that the message content may be partially cut off if `finish_reason="length"`, which indicates the generation exceeded `max_tokens` or the conversation exceeded the max context length.
| |
| `Seed` | **int64* | :heavy_minus_sign: | This feature is in Beta.
If specified, our 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.
| |
| `Stop` | [*components.Stop](../../models/components/stop.md) | :heavy_minus_sign: | Up to 4 sequences where the API will stop generating further tokens.
| |
| `Stream` | **bool* | :heavy_minus_sign: | If set, partial message deltas will be sent, like in ChatGPT. Tokens will be sent as data-only [server-sent events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events#Event_stream_format) as they become available, with the stream terminated by a `data: [DONE]` message. [Example Python code](https://cookbook.openai.com/examples/how_to_stream_completions).
| |
| `StreamOptions` | [*components.ChatCompletionStreamOptions](../../models/components/chatcompletionstreamoptions.md) | :heavy_minus_sign: | Options for streaming response. Only set this when you set `stream: true`.
| |
| `Temperature` | **float64* | :heavy_minus_sign: | What sampling temperature to use, 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.
We generally recommend altering this or `top_p` but not both.
| 1 |
| `TopP` | **float64* | :heavy_minus_sign: | 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.
We generally recommend altering this or `temperature` but not both.
| 1 |
| `Tools` | [][components.ChatCompletionTool](../../models/components/chatcompletiontool.md) | :heavy_minus_sign: | A list of tools the model may call. Currently, only functions are supported as a tool. Use this to provide a list of functions the model may generate JSON inputs for. A max of 128 functions are supported.
| |
| `ToolChoice` | [*components.ChatCompletionToolChoiceOption](../../models/components/chatcompletiontoolchoiceoption.md) | :heavy_minus_sign: | Controls which (if any) tool is called by the model.
`none` means the model will not call any tool and instead generates a message.
`auto` means the model can pick between generating a message or calling one or more tools.
`required` means the model must call one or more tools.
Specifying a particular tool via `{"type": "function", "function": {"name": "my_function"}}` forces the model to call that tool.
`none` is the default when no tools are present. `auto` is the default if tools are present.
| |
| `User` | **string* | :heavy_minus_sign: | A unique identifier representing your end-user, which can help OpenAI to monitor and detect abuse. [Learn more](/docs/guides/safety-best-practices/end-user-ids).
| user-1234 |
| ~~`FunctionCall`~~ | [*components.CreateChatCompletionRequestFunctionCall](../../models/components/createchatcompletionrequestfunctioncall.md) | :heavy_minus_sign: | : warning: ** DEPRECATED **: This will be removed in a future release, please migrate away from it as soon as possible.
Deprecated in favor of `tool_choice`.
Controls which (if any) function is called by the model.
`none` means the model will not call a function and instead generates a message.
`auto` means the model can pick between generating a message or calling a function.
Specifying a particular function via `{"name": "my_function"}` forces the model to call that function.
`none` is the default when no functions are present. `auto` is the default if functions are present.
| |
| ~~`Functions`~~ | [][components.ChatCompletionFunctions](../../models/components/chatcompletionfunctions.md) | :heavy_minus_sign: | : warning: ** DEPRECATED **: This will be removed in a future release, please migrate away from it as soon as possible.
Deprecated in favor of `tools`.
A list of functions the model may generate JSON inputs for.
| |