POST
/assistants/{assistant_id}DeprecatedModify an assistant
Updates an existing assistant's model, instructions, tools, resources, metadata, or generation settings. Supply only the assistant properties you want to change, while using assistant_id to select the assistant. This operation is deprecated.
- RetriesRetries up to 2×, 500ms backoff, 30s timeout.
assistant_idstringrequired
Identifier of the assistant to modify.
Assistant properties to update, including model, instructions, tools, resources, metadata, and generation settings.
modelstringoptional
ID of the model to use. You can use the [List models](https://developers.openai.com/api/reference/resources/models/methods/list) API to see all of your available models, or see our [Model overview](https://developers.openai.com/api/docs/models) for descriptions of them.
reasoning_effortstringoptional
Reasoning effort for supported reasoning models: `none`, `minimal`, `low`, `medium`, `high`, `xhigh`, or `max`. Defaults to `medium` when omitted; set to null to clear it.
namestringoptional
Assistant name. Maximum 256 characters; set it to null to clear it.
descriptionstringoptional
Assistant description. Maximum 512 characters; set it to null to clear it.
instructionsstringoptional
System instructions for the assistant. Maximum 256,000 characters; set it to null to clear them.
toolsarray<CodeInterpreterTool>optional
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`.
tool_resourcesobjectoptional
Resources used by the assistant's tools, such as code interpreter file IDs or file search vector store IDs; set to null to clear them.
metadataobjectoptional
String key-value pairs attached to the assistant; keys can be at most 64 characters and values are strings, or set to null to clear them.
temperaturenumberoptional
Sampling temperature from 0 to 2; set to null to clear it.
top_pnumberoptional
Nucleus sampling probability from 0 to 1; set to null to clear it.
response_formatstring | objectoptional
Output format requested from the model, using one of the supported string or structured response format definitions; set to null to clear it.
200Returns the updated assistant object with its current model, instructions, tools, metadata, and generation settings.
idstringrequired
The identifier, which can be referenced in API endpoints.
objectstringrequired
The object type, which is always `assistant`.
created_atintegerrequired
The Unix timestamp (in seconds) for when the assistant was created.
namestringrequired
The name of the assistant. The maximum length is 256 characters.
descriptionstringrequired
The description of the assistant. The maximum length is 512 characters.
modelstringrequired
ID of the model to use. You can use the [List models](https://developers.openai.com/api/reference/resources/models/methods/list) API to see all of your available models, or see our [Model overview](https://developers.openai.com/api/docs/models) for descriptions of them.
instructionsstringrequired
The system instructions that the assistant uses. The maximum length is 256,000 characters.
toolsarray<CodeInterpreterTool>required
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`.
tool_resourcesobjectoptional
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.
metadataobjectrequired
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.
temperaturenumberoptional
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.
top_pnumberoptional
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.
response_formatstring | objectoptional
Specifies the format that the model must output. Compatible with [GPT-4o](https://developers.openai.com/api/docs/models/gpt-4o), [GPT-4 Turbo](https://developers.openai.com/api/docs/models/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](https://developers.openai.com/api/docs/guides/structured-outputs).
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.
429Returned when the request was rejected because the rate limit was exceeded.
errorobjectrequired
Error handling
A 429 is returned when the request exceeds the rate limit. assistant_id must identify the assistant to modify; tools can contain at most 128 tools, name at most 256 characters, description at most 512 characters, and instructions at most 256,000 characters.