---
title: "Changes to Create assistant"
method: POST
path: "/assistants"
---

# Changes to Create assistant

`POST /assistants`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 2 of 88 revisions.

- **2026-10-06** `487892d3954e`: 1 info
- **2026-10-05** `7f654af7f94f`: 23 breaking, 4 warning, 22 info

## Changes

- **2026-10-06** `487892d3954e`: 1 info
  - added the optional property `error/misalignment/review_target` to the response with the `429` status
- **2026-10-05** `7f654af7f94f`: 23 breaking, 4 warning, 22 info
  - removed `subschema #2` from the `model` request property `anyOf` list
  - the request property `description` became not nullable
  - the request property `instructions` became not nullable
  - the request property `metadata` became not nullable
  - the request property `name` became not nullable
  - the request property `response_format` became not nullable
  - the request property `temperature` became not nullable
  - the request property `tool_resources` became not nullable
  - the request property `tools/items/oneOf[subschema #3: Function tool]/function/strict` became not nullable
  - the request property `top_p` became not nullable
  - removed `#/components/schemas/ResponseFormatText, #/components/schemas/ResponseFormatJsonObject, #/components/schemas/ResponseFormatJsonSchema, subschema #1` from the `response_format` request property `oneOf` list
  - the `tool_resources` request property type changed from `object` to no type
  - response property `description` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `instructions` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `metadata` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `name` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `temperature` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `tools/items/oneOf[subschema #3: Function tool]/function/strict` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - response property `top_p` list-of-types was widened by adding types `null` to media type `application/json` of response `200`
  - the `description` response property's maxLength was unset from `512` for the response status `200`
  - the `instructions` response property's maxLength was unset from `256000` for the response status `200`
  - the `name` response property's maxLength was unset from `256` for the response status `200`
  - the `tool_resources` response's property type changed from `object` to no type for status `200`
  - removed the request property `tool_resources/code_interpreter`
  - removed the request property `tool_resources/file_search`
  - removed the optional property `tool_resources/code_interpreter` from the response with the `200` status
  - removed the optional property `tool_resources/file_search` from the response with the `200` status
  - endpoint deprecated
  - added the new optional request property `reasoning_effort`
  - added `#/components/schemas/AssistantSupportedModels` to the `model` request property `anyOf` list
  - added `#/components/schemas/AssistantsApiResponseFormatOption, subschema #2` to the `response_format` request property `anyOf` list
  - added `subschema #1, subschema #2` to the `tool_resources` request property `anyOf` list
  - the `strict` request property default value `false` was removed
  - the `temperature` request property default value `1` was removed
  - the `top_p` request property default value `1` was removed
  - request property `description` list-of-types was widened by adding types `null` to media type `application/json`
  - request property `instructions` list-of-types was widened by adding types `null` to media type `application/json`
  - request property `metadata` list-of-types was widened by adding types `null` to media type `application/json`
  - request property `name` list-of-types was widened by adding types `null` to media type `application/json`
  - request property `temperature` list-of-types was widened by adding types `null` to media type `application/json`
  - …9 more

---

[Operation](https://skmtc.dev/omnistack-sh/apis/openai-api/docs/assistants/post.md) - [API](https://skmtc.dev/omnistack-sh/apis/openai-api.md) - [Page](https://skmtc.dev/omnistack-sh/apis/openai-api/changes/assistants/post)