---
title: "Changes to Create a chat completion"
method: POST
path: "/api/chat/completions"
---

# Changes to Create a chat completion

`POST /api/chat/completions`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 4 of 12 revisions.

- **2026-10-21** `c30bcb383ee8`: 8 breaking, 22 info
- **2026-10-02** `b830b79cfd52`: 2 info
- **2026-09-17** `6fa8242da8c2`: 1 warning, 1 info
- **2026-09-12** `22b868ef3f22`: 1 info

## Changes

- **2026-10-21** `c30bcb383ee8`: 8 breaking, 22 info
  - request body became required
  - removed the media type `application/json` for the response with the status `401`
  - the response property `error/code` became nullable for the status `400`
  - the response property `error/code` became nullable for the status `404`
  - the response property `error/code` became nullable for the status `424`
  - the response property `error/param` became nullable for the status `400`
  - the response property `error/param` became nullable for the status `404`
  - the response property `error/param` became nullable for the status `424`
  - api operation id `gateway_createChatCompletion` removed and replaced with `createChatCompletion`
  - api tag `Gateway` added
  - api tag `gateway` removed
  - the `exclude_models` request property default value `[]` was added
  - the `exclude_providers` request property default value `[]` was added
  - the `logprobs` request property default value `false` was added
  - the `request_breakdown` request property default value `false` was added
  - the `stream` request property default value `false` was added
  - the `cache_ttl` request property format was generalized from `double` to no format
  - the `frequency_penalty` request property format was generalized from `double` to no format
  - the `max_tokens` request property format was generalized from `double` to no format
  - the `n` request property format was generalized from `double` to no format
  - the `presence_penalty` request property format was generalized from `double` to no format
  - the `temperature` request property format was generalized from `double` to no format
  - the `weight` request property format was generalized from `double` to no format
  - added the media type `text/event-stream` for the response with the status `200`
  - removed `subschema #1, subschema #2` from the `error/code` response property `oneOf` list for the response status `400`
  - removed `subschema #1, subschema #2` from the `error/code` response property `oneOf` list for the response status `404`
  - removed `subschema #1, subschema #2` from the `error/code` response property `oneOf` list for the response status `424`
  - removed `subschema #1, subschema #2` from the `error/param` response property `oneOf` list for the response status `400`
  - removed `subschema #1, subschema #2` from the `error/param` response property `oneOf` list for the response status `404`
  - removed `subschema #1, subschema #2` from the `error/param` response property `oneOf` list for the response status `424`
- **2026-10-02** `b830b79cfd52`: 2 info
  - added the non-success response with the status `403`
  - added the non-success response with the status `404`
- **2026-09-17** `6fa8242da8c2`: 1 warning, 1 info
  - deleted the `header` request parameter `Authorization`
  - the endpoint scheme security `RespanApiKey` was added to the API
- **2026-09-12** `22b868ef3f22`: 1 info
  - api operation id `create-chat-completion` removed and replaced with `gateway_createChatCompletion`

---

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