---
title: "Changes to Responses Api"
method: POST
path: "/responses"
---

# Changes to Responses Api

`POST /responses`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 1 of 4 revisions.

- **2026-10-16** `8efc7e7a4ee4`: 2 breaking, 24 info

## Changes

- **2026-10-16** `8efc7e7a4ee4`: 2 breaking, 24 info
  - added required request body
  - the response's body type changed from no type to `object` for status `200`
  - added the media type `text/event-stream` for the response with the status `200`
  - added the optional property `error` to the response with the `200` status
  - added the optional property `incomplete_details` to the response with the `200` status
  - added the optional property `instructions` to the response with the `200` status
  - added the optional property `max_output_tokens` to the response with the `200` status
  - added the optional property `metadata` to the response with the `200` status
  - added the optional property `model` to the response with the `200` status
  - added the optional property `object` to the response with the `200` status
  - added the optional property `parallel_tool_calls` to the response with the `200` status
  - added the optional property `previous_response_id` to the response with the `200` status
  - added the optional property `reasoning` to the response with the `200` status
  - added the optional property `status` to the response with the `200` status
  - added the optional property `store` to the response with the `200` status
  - added the optional property `temperature` to the response with the `200` status
  - added the optional property `text` to the response with the `200` status
  - added the optional property `tool_choice` to the response with the `200` status
  - added the optional property `tools` to the response with the `200` status
  - added the optional property `top_p` to the response with the `200` status
  - added the optional property `truncation` to the response with the `200` status
  - added the optional property `usage` to the response with the `200` status
  - added the optional property `user` to the response with the `200` status
  - added the required property `created_at` to the response with the `200` status
  - added the required property `id` to the response with the `200` status
  - added the required property `output` to the response with the `200` status

---

[Operation](https://skmtc.dev/mammouth/apis/mammouth-api/docs/responses/post.md) - [API](https://skmtc.dev/mammouth/apis/mammouth-api.md) - [Page](https://skmtc.dev/mammouth/apis/mammouth-api/changes/responses/post)