Skip to content
Primary navigation

Methods

ModelsExpand Collapse
dpo_hyperparameters: object { batch_size, beta, learning_rate_multiplier, n_epochs }

The hyperparameters used for the DPO fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
beta: optional "auto" or number

The beta value for the DPO method. A higher beta value will increase the weight of the penalty between the policy and reference model.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number
dpo_method: object { hyperparameters }

Configuration for the DPO fine-tuning method.

hyperparameters: optional object { batch_size, beta, learning_rate_multiplier, n_epochs }

The hyperparameters used for the DPO fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
beta: optional "auto" or number

The beta value for the DPO method. A higher beta value will increase the weight of the penalty between the policy and reference model.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number
reinforcement_hyperparameters: object { batch_size, compute_multiplier, eval_interval, 4 more }

The hyperparameters used for the reinforcement fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
compute_multiplier: optional "auto" or number

Multiplier on amount of compute used for exploring search space during training.

union_member_0: "auto"
union_member_1: number
eval_interval: optional "auto" or number

The number of training steps between evaluation runs.

union_member_0: "auto"
union_member_1: number
eval_samples: optional "auto" or number

Number of evaluation samples to generate per training step.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number
reasoning_effort: optional "default" or "low" or "medium" or "high"

Level of reasoning effort.

"default"
"low"
"medium"
"high"
reinforcement_method: object { grader, hyperparameters }

Configuration for the reinforcement fine-tuning method.

grader: StringCheckGrader { input, name, operation, 2 more } or TextSimilarityGrader { evaluation_metric, input, name, 2 more } or PythonGrader { name, source, type, image_tag } or 2 more

The grader used for the fine-tuning job.

string_check_grader: object { input, name, operation, 2 more }

A StringCheckGrader object that performs a string comparison between input and reference using a specified operation.

input: string

The input text. This may include template strings.

name: string

The name of the grader.

operation: "eq" or "ne" or "like" or "ilike"

The string check operation to perform. One of eq, ne, like, or ilike.

"eq"
"ne"
"like"
"ilike"
reference: string

The reference text. This may include template strings.

type: "string_check"

The object type, which is always string_check.

text_similarity_grader: object { evaluation_metric, input, name, 2 more }

A TextSimilarityGrader object which grades text based on similarity metrics.

evaluation_metric: "cosine" or "fuzzy_match" or "bleu" or 8 more

The evaluation metric to use. One of cosine, fuzzy_match, bleu, gleu, meteor, rouge_1, rouge_2, rouge_3, rouge_4, rouge_5, or rouge_l.

"cosine"
"fuzzy_match"
"bleu"
"gleu"
"meteor"
"rouge_1"
"rouge_2"
"rouge_3"
"rouge_4"
"rouge_5"
"rouge_l"
input: string

The text being graded.

name: string

The name of the grader.

reference: string

The text being graded against.

type: "text_similarity"

The type of grader.

python_grader: object { name, source, type, image_tag }

A PythonGrader object that runs a python script on the input.

name: string

The name of the grader.

source: string

The source code of the python script.

type: "python"

The object type, which is always python.

image_tag: optional string

The image tag to use for the python script.

score_model_grader: object { input, model, name, 3 more }

A ScoreModelGrader object that uses a model to assign a score to the input.

input: array of object { content, role, type }

The input messages evaluated by the grader. Supports text, output text, input image, and input audio content blocks, and may include template strings.

content: string or ResponseInputText { text, type } or object { text, type } or 3 more

Inputs to the model - can contain template strings. Supports text, output text, input images, and input audio, either as a single item or an array of items.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

grader_inputs: array of string or ResponseInputText { text, type } or object { text, type } or 2 more

A list of inputs, each of which may be either an input text, output text, input image, or input audio object.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

role: "user" or "assistant" or "system" or "developer"

The role of the message input. One of user, assistant, system, or developer.

"user"
"assistant"
"system"
"developer"
type: optional "message"

The type of the message input. Always message.

"message"
model: string

The model to use for the evaluation.

name: string

The name of the grader.

type: "score_model"

The object type, which is always score_model.

range: optional array of number

The range of the score. Defaults to [0, 1].

sampling_params: optional object { max_completions_tokens, reasoning_effort, seed, 2 more }

The sampling parameters for the model.

max_completions_tokens: optional number

The maximum number of tokens the grader model may generate in its response.

reasoning_effort: optional "none" or "minimal" or "low" or 3 more

Constrains effort on reasoning for reasoning models. Currently supported values are none, minimal, low, medium, high, and xhigh. Reducing reasoning effort can result in faster responses and fewer tokens used on reasoning in a response.

  • gpt-5.1 defaults to none, which does not perform reasoning. The supported reasoning values for gpt-5.1 are none, low, medium, and high. Tool calls are supported for all reasoning values in gpt-5.1.
  • All models before gpt-5.1 default to medium reasoning effort, and do not support none.
  • The gpt-5-pro model defaults to (and only supports) high reasoning effort.
  • xhigh is supported for all models after gpt-5.1-codex-max.
"none"
"minimal"
"low"
"medium"
"high"
"xhigh"
seed: optional number

A seed value to initialize the randomness, during sampling.

temperature: optional number

A higher temperature increases randomness in the outputs.

top_p: optional number

An alternative to temperature for nucleus sampling; 1.0 includes all tokens.

multi_grader: object { calculate_output, graders, name, type }

A MultiGrader object combines the output of multiple graders to produce a single score.

calculate_output: string

A formula to calculate the output based on grader results.

graders: StringCheckGrader { input, name, operation, 2 more } or TextSimilarityGrader { evaluation_metric, input, name, 2 more } or PythonGrader { name, source, type, image_tag } or 2 more

A StringCheckGrader object that performs a string comparison between input and reference using a specified operation.

string_check_grader: object { input, name, operation, 2 more }

A StringCheckGrader object that performs a string comparison between input and reference using a specified operation.

input: string

The input text. This may include template strings.

name: string

The name of the grader.

operation: "eq" or "ne" or "like" or "ilike"

The string check operation to perform. One of eq, ne, like, or ilike.

"eq"
"ne"
"like"
"ilike"
reference: string

The reference text. This may include template strings.

type: "string_check"

The object type, which is always string_check.

text_similarity_grader: object { evaluation_metric, input, name, 2 more }

A TextSimilarityGrader object which grades text based on similarity metrics.

evaluation_metric: "cosine" or "fuzzy_match" or "bleu" or 8 more

The evaluation metric to use. One of cosine, fuzzy_match, bleu, gleu, meteor, rouge_1, rouge_2, rouge_3, rouge_4, rouge_5, or rouge_l.

"cosine"
"fuzzy_match"
"bleu"
"gleu"
"meteor"
"rouge_1"
"rouge_2"
"rouge_3"
"rouge_4"
"rouge_5"
"rouge_l"
input: string

The text being graded.

name: string

The name of the grader.

reference: string

The text being graded against.

type: "text_similarity"

The type of grader.

python_grader: object { name, source, type, image_tag }

A PythonGrader object that runs a python script on the input.

name: string

The name of the grader.

source: string

The source code of the python script.

type: "python"

The object type, which is always python.

image_tag: optional string

The image tag to use for the python script.

score_model_grader: object { input, model, name, 3 more }

A ScoreModelGrader object that uses a model to assign a score to the input.

input: array of object { content, role, type }

The input messages evaluated by the grader. Supports text, output text, input image, and input audio content blocks, and may include template strings.

content: string or ResponseInputText { text, type } or object { text, type } or 3 more

Inputs to the model - can contain template strings. Supports text, output text, input images, and input audio, either as a single item or an array of items.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

grader_inputs: array of string or ResponseInputText { text, type } or object { text, type } or 2 more

A list of inputs, each of which may be either an input text, output text, input image, or input audio object.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

role: "user" or "assistant" or "system" or "developer"

The role of the message input. One of user, assistant, system, or developer.

"user"
"assistant"
"system"
"developer"
type: optional "message"

The type of the message input. Always message.

"message"
model: string

The model to use for the evaluation.

name: string

The name of the grader.

type: "score_model"

The object type, which is always score_model.

range: optional array of number

The range of the score. Defaults to [0, 1].

sampling_params: optional object { max_completions_tokens, reasoning_effort, seed, 2 more }

The sampling parameters for the model.

max_completions_tokens: optional number

The maximum number of tokens the grader model may generate in its response.

reasoning_effort: optional "none" or "minimal" or "low" or 3 more

Constrains effort on reasoning for reasoning models. Currently supported values are none, minimal, low, medium, high, and xhigh. Reducing reasoning effort can result in faster responses and fewer tokens used on reasoning in a response.

  • gpt-5.1 defaults to none, which does not perform reasoning. The supported reasoning values for gpt-5.1 are none, low, medium, and high. Tool calls are supported for all reasoning values in gpt-5.1.
  • All models before gpt-5.1 default to medium reasoning effort, and do not support none.
  • The gpt-5-pro model defaults to (and only supports) high reasoning effort.
  • xhigh is supported for all models after gpt-5.1-codex-max.
"none"
"minimal"
"low"
"medium"
"high"
"xhigh"
seed: optional number

A seed value to initialize the randomness, during sampling.

temperature: optional number

A higher temperature increases randomness in the outputs.

top_p: optional number

An alternative to temperature for nucleus sampling; 1.0 includes all tokens.

label_model_grader: object { input, labels, model, 3 more }

A LabelModelGrader object which uses a model to assign labels to each item in the evaluation.

input: array of object { content, role, type }
content: string or ResponseInputText { text, type } or object { text, type } or 3 more

Inputs to the model - can contain template strings. Supports text, output text, input images, and input audio, either as a single item or an array of items.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

grader_inputs: array of string or ResponseInputText { text, type } or object { text, type } or 2 more

A list of inputs, each of which may be either an input text, output text, input image, or input audio object.

Text input: string

A text input to the model.

response_input_text: object { text, type }

A text input to the model.

text: string

The text input to the model.

type: "input_text"

The type of the input item. Always input_text.

Output text: object { text, type }

A text output from the model.

text: string

The text output from the model.

type: "output_text"

The type of the output text. Always output_text.

Input image: object { image_url, type, detail }

An image input block used within EvalItem content arrays.

image_url: string

The URL of the image input.

type: "input_image"

The type of the image input. Always input_image.

detail: optional string

The detail level of the image to be sent to the model. One of high, low, or auto. Defaults to auto.

response_input_audio: object { input_audio, type }

An audio input to the model.

input_audio: object { data, format }
data: string

Base64-encoded audio data.

format: "mp3" or "wav"

The format of the audio data. Currently supported formats are mp3 and wav.

"mp3"
"wav"
type: "input_audio"

The type of the input item. Always input_audio.

role: "user" or "assistant" or "system" or "developer"

The role of the message input. One of user, assistant, system, or developer.

"user"
"assistant"
"system"
"developer"
type: optional "message"

The type of the message input. Always message.

"message"
labels: array of string

The labels to assign to each item in the evaluation.

model: string

The model to use for the evaluation. Must support structured outputs.

name: string

The name of the grader.

passing_labels: array of string

The labels that indicate a passing result. Must be a subset of labels.

type: "label_model"

The object type, which is always label_model.

name: string

The name of the grader.

type: "multi"

The object type, which is always multi.

hyperparameters: optional object { batch_size, compute_multiplier, eval_interval, 4 more }

The hyperparameters used for the reinforcement fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
compute_multiplier: optional "auto" or number

Multiplier on amount of compute used for exploring search space during training.

union_member_0: "auto"
union_member_1: number
eval_interval: optional "auto" or number

The number of training steps between evaluation runs.

union_member_0: "auto"
union_member_1: number
eval_samples: optional "auto" or number

Number of evaluation samples to generate per training step.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number
reasoning_effort: optional "default" or "low" or "medium" or "high"

Level of reasoning effort.

"default"
"low"
"medium"
"high"
supervised_hyperparameters: object { batch_size, learning_rate_multiplier, n_epochs }

The hyperparameters used for the fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number
supervised_method: object { hyperparameters }

Configuration for the supervised fine-tuning method.

hyperparameters: optional object { batch_size, learning_rate_multiplier, n_epochs }

The hyperparameters used for the fine-tuning job.

batch_size: optional "auto" or number

Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.

union_member_0: "auto"
union_member_1: number
learning_rate_multiplier: optional "auto" or number

Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.

union_member_0: "auto"
union_member_1: number
n_epochs: optional "auto" or number

The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.

union_member_0: "auto"
union_member_1: number