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

# Changes to Create a chat completion

`POST /chat/completions`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 1 of 2 revisions.

- **2026-11-03** `d63ac1749ae7`: 1 breaking, 2 warning, 12 info

## Changes

- **2026-11-03** `d63ac1749ae7`: 1 breaking, 2 warning, 12 info
  - removed the enum value `priority` of the request property `metadata/completion_window`
  - added the new `content_filter` enum value to the `choices/items/finish_reason` response property for the response status `200` (media type: text/event-stream)
  - added the new `length` enum value to the `choices/items/finish_reason` response property for the response status `200` (media type: text/event-stream)
  - added the new optional `header` request parameter `X-Sail-Completion-Window`
  - added the new optional request property `metadata/supercache_write`
  - added the new optional request property `prompt_cache_key`
  - added the new `balanced` enum value to the request property `metadata/completion_window`
  - added the new `max` enum value to the request property `reasoning_effort/oneOf[subschema #1]/`
  - added `#/components/schemas/ChatFileContentPart` to the `messages/items/content/oneOf[subschema #3]/items/` request property `oneOf` list
  - added the non-success response with the status `409`
  - added the non-success response with the status `503`
  - added the non-success response with the status `504`
  - removed the non-success response with the status `408`
  - added the optional property `service_tier` to the response with the `200` status (media type: application/json)
  - added the optional property `service_tier` to the response with the `200` status (media type: text/event-stream)

---

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