# Release 2026.10.27

> API changes

Source: https://docs.serenityedge.ai/release-notes/2026-10-27/
Published: 2026-10-27

October 27, 2026

## API changes

### Responses API

`POST /v1/responses` serves OpenAI's Responses API on every chat model, with the same keys, prices and limits as chat completions. It covers:

-   text and image input;
-   function tools;
-   structured outputs (`text.format`);
-   reasoning;
-   streaming with Responses events.

The OpenAI SDKs' `client.responses.create`, `client.responses.stream` and `client.responses.parse` work as they are.

The API is stateless, since Serenity Edge stores no prompts or answers. Send the whole conversation in `input` on every request. `store: true`, `previous_response_id`, `conversation` and `background` are refused with HTTP 400, and responses cannot be retrieved. See the [Responses API guide](https://docs.serenityedge.ai/docs/responses-api/).

### Decision request limits

`POST /v1/decisions` and the Jev-compatible `POST /v1/systemone` accept at most 256 questions per request; `POST /v1/decisions` also takes at most 255 options per `choice` question and 10 levels per `score` question. A larger request is refused, with HTTP 400 (422 on `POST /v1/systemone`), a message that says which limit was hit, and the parameter at fault in `param`. See [Current limitations](https://docs.serenityedge.ai/docs/decisions/#current-limitations).

### Clearer validation errors on decisions

On `orion-compass`, `orion-compass-flash` and `d3`, the error for a malformed decision request now names the field and how to fix it, and the three models refuse the same requests on `POST /v1/systemone` with the same messages. For example, a choice given as a string gets "each choice must be an object with a 'value' (string or boolean)", and a question whose text is in `question` instead of `instructions` is told so. `param` points at the exact element, such as `questions[0].choices[0]`. See [Errors](https://docs.serenityedge.ai/docs/decisions/#errors).

* * *

## Documentation

-   New guide: [Responses API](https://docs.serenityedge.ai/docs/responses-api/).
-   The [API reference](https://docs.serenityedge.ai/docs/api/edge/create-response/) documents `POST /v1/responses`.