Body Required

• model string

  ID of the model to use. You can use the List models API to see all of your available models, or see our Model overview for descriptions of them.

  Any of:

  string-1 string AssistantSupportedModels string

  Values are o3-mini, o3-mini-2025-01-31, o1, o1-2024-12-17, gpt-4o, gpt-4o-2024-11-20, gpt-4o-2024-08-06, gpt-4o-2024-05-13, gpt-4o-mini, gpt-4o-mini-2024-07-18, gpt-4.5-preview, gpt-4.5-preview-2025-02-27, gpt-4-turbo, gpt-4-turbo-2024-04-09, gpt-4-0125-preview, gpt-4-turbo-preview, gpt-4-1106-preview, gpt-4-vision-preview, gpt-4, gpt-4-0314, gpt-4-0613, gpt-4-32k, gpt-4-32k-0314, gpt-4-32k-0613, gpt-3.5-turbo, gpt-3.5-turbo-16k, gpt-3.5-turbo-0613, gpt-3.5-turbo-1106, gpt-3.5-turbo-0125, or gpt-3.5-turbo-16k-0613.

• reasoning_effort string | null

  o-series models only

  Constrains effort on reasoning for reasoning models. Currently supported values are low, medium, and high. Reducing reasoning effort can result in faster responses and fewer tokens used on reasoning in a response.

  Values are low, medium, or high. Default value is medium.

• name string | null

  The name of the assistant. The maximum length is 256 characters.

  Maximum length is 256.

• description string | null

  The description of the assistant. The maximum length is 512 characters.

  Maximum length is 512.

• instructions string | null

  The system instructions that the assistant uses. The maximum length is 256,000 characters.

  Maximum length is 256000.

• tools array[object]

  A list of tool enabled on the assistant. There can be a maximum of 128 tools per assistant. Tools can be of types code_interpreter, file_search, or function.

  Not more than 128 elements. Default value is [] (empty).

  One of:

  AssistantToolsCode object AssistantToolsFileSearch object AssistantToolsFunction object

  Hide attribute Show attribute

  • type string Required

    The type of tool being defined: code_interpreter

    Value is code_interpreter.

  Hide attributes Show attributes

  • type string Required

    The type of tool being defined: file_search

    Value is file_search.

  • file_search object

    Overrides for the file search tool.

    Hide file_search attributes Show file_search attributes object

    • max_num_results integer

      The maximum number of results the file search tool should output. The default is 20 for gpt-4* models and 5 for gpt-3.5-turbo. This number should be between 1 and 50 inclusive.

      Note that the file search tool may output fewer than max_num_results results. See the file search tool documentation for more information.

      Minimum value is 1, maximum value is 50.

    • ranking_options object

      The ranking options for the file search. If not specified, the file search tool will use the auto ranker and a score_threshold of 0.

      See the file search tool documentation for more information.

      Hide ranking_options attributes Show ranking_options attributes object

      • ranker string

        The ranker to use for the file search. If not specified will use the auto ranker.

        Values are auto or default_2024_08_21.

      • score_threshold number Required

        The score threshold for the file search. All values must be a floating point number between 0 and 1.

        Minimum value is 0, maximum value is 1.

  Hide attributes Show attributes

  • type string Required

    The type of tool being defined: function

    Value is function.

  • function object Required
    Hide function attributes Show function attributes object

    • description string

      A description of what the function does, used by the model to choose when and how to call the function.

    • name string Required

      The name of the function to be called. Must be a-z, A-Z, 0-9, or contain underscores and dashes, with a maximum length of 64.

    • parameters object

      The parameters the functions accepts, described as a JSON Schema object. See the guide for examples, and the JSON Schema reference for documentation about the format.

      Omitting parameters defines a function with an empty parameter list.

      Additional properties are allowed.

    • strict boolean | null

      Whether to enable strict schema adherence when generating the function call. If set to true, the model will follow the exact schema defined in the parameters field. Only a subset of JSON Schema is supported when strict is true. Learn more about Structured Outputs in the function calling guide.

      Default value is false.

• tool_resources object | null

  A set of resources that are used by the assistant's tools. The resources are specific to the type of tool. For example, the code_interpreter tool requires a list of file IDs, while the file_search tool requires a list of vector store IDs.

  Hide tool_resources attributes Show tool_resources attributes object | null

  • code_interpreter object
    Hide code_interpreter attribute Show code_interpreter attribute object

    • file_ids array[string]

      Overrides the list of file IDs made available to the code_interpreter tool. There can be a maximum of 20 files associated with the tool.

      Not more than 20 elements. Default value is [] (empty).

  • file_search object
    Hide file_search attribute Show file_search attribute object

    • vector_store_ids array[string]

      Overrides the vector store attached to this assistant. There can be a maximum of 1 vector store attached to the assistant.

      Not more than 1 element.

• metadata object | null

  Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format, and querying for objects via API or the dashboard.

  Keys are strings with a maximum length of 64 characters. Values are strings with a maximum length of 512 characters.

  Hide metadata attribute Show metadata attribute object | null

  • * string Additional properties
• temperature number | null

  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.

  Minimum value is 0, maximum value is 2. Default value is 1.

• top_p number | null

  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.

  Minimum value is 0, maximum value is 1. Default value is 1.

• response_format string | null | object

  Specifies the format that the model must output. Compatible with GPT-4o, GPT-4 Turbo, and all GPT-3.5 Turbo models since gpt-3.5-turbo-1106.

  Setting to { "type": "json_schema", "json_schema": {...} } enables Structured Outputs which ensures the model will match your supplied JSON schema. Learn more in the Structured Outputs guide.

  Setting to { "type": "json_object" } enables JSON mode, which ensures 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.

  One of:

  string-1 string | null ResponseFormatText object | null ResponseFormatJsonObject object | null ResponseFormatJsonSchema object | null

  auto is the default value

  Value is auto.

  Default response format. Used to generate text responses.

  Hide attribute Show attribute

  • type string Required

    The type of response format being defined. Always text.

    Value is text.

  JSON object response format. An older method of generating JSON responses. Using json_schema is recommended for models that support it. Note that the model will not generate JSON without a system or user message instructing it to do so.

  Hide attribute Show attribute

  • type string Required

    The type of response format being defined. Always json_object.

    Value is json_object.

  JSON Schema response format. Used to generate structured JSON responses. Learn more about Structured Outputs.

  Hide attributes Show attributes

  • type string Required

    The type of response format being defined. Always json_schema.

    Value is json_schema.

  • json_schema object Required

    Structured Outputs configuration options, including a JSON Schema.

    Hide json_schema attributes Show json_schema attributes object

    • description string

      A description of what the response format is for, used by the model to determine how to respond in the format.

    • name string Required

      The name of the response format. Must be a-z, A-Z, 0-9, or contain underscores and dashes, with a maximum length of 64.

    • schema object

      The schema for the response format, described as a JSON Schema object. Learn how to build JSON schemas here.

      Additional properties are allowed.

    • strict boolean | null

      Whether to enable strict schema adherence when generating the output. If set to true, the model will always follow the exact schema defined in the schema field. Only a subset of JSON Schema is supported when strict is true. To learn more, read the Structured Outputs guide.

      Default value is false.