---
title: "Changes to Foundational Time Series Model Multi Series Cross Validation"
method: POST
path: "/v2/cross_validation"
---

# Changes to Foundational Time Series Model Multi Series Cross Validation

`POST /v2/cross_validation`

> Every recorded change to this endpoint, newest first.

## Timeline

Changed in 2 of 10 revisions.

- **2026-08-07** `a3b589142eba` — 1 info
- **2026-06-30** `9da3f4939623` — 1 breaking, 12 info

## Changes

- **2026-08-07** `a3b589142eba` — 1 info
  - added the new optional request property `feature_contributions_type`
- **2026-06-30** `9da3f4939623` — 1 breaking, 12 info
  - the `model` request property type/format changed from ``/`` to `string`/``
  - added the new optional request property `feature_contributions`
  - added the new optional request property `full_history`
  - added the new optional request property `model_parameters`
  - added the new optional request property `multivariate`
  - added the new optional request property `series/X_future`
  - added the new optional request property `series/categorical_exog`
  - the request property `n_windows` became optional
  - the `n_windows` request property default value `1` was added
  - request property `series/X/anyOf[subschema #1]/items/items/` list-of-types was widened by adding types `string` to media type `application/json`
  - added the optional property `detail/items/ctx` to the response with the `422` status
  - added the optional property `detail/items/input` to the response with the `422` status
  - added the optional property `feature_contributions` to the response with the `200` status

---

[Operation](https://skmtc.dev/nixtla/apis/nixtla-forecast-api/docs/v2/cross_validation/post.md) · [API](https://skmtc.dev/nixtla/apis/nixtla-forecast-api.md) · [Page](https://skmtc.dev/nixtla/apis/nixtla-forecast-api/changes/v2/cross_validation/post)