> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fintoc.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Changes to the API

> Track changes and upgrades to the Fintoc API

This page explains which API changes Fintoc treats as backwards compatible and how Fintoc versions changes that are not backwards compatible. Every API change to date has been backwards compatible. For a change that is not backwards compatible, Fintoc releases a new dated API version so your existing integration keeps working.

## Backwards-compatible changes

Fintoc considers the following changes backwards compatible:

* Add objects to the API.
* Add optional parameters to existing API endpoints.
* Add new fields to existing objects.
* Change the order of the keys in an object.
* Change the length or format of IDs and tokens, including adding or removing prefixes such as the `acc_` prefix on the [`Account` object](/api/movements-api/accounts/accounts-object) ID.
* Change header field names to uppercase or lowercase. Per [RFC 7230](https://www.rfc-editor.org/rfc/rfc7230#section-3.2), header field names are case-insensitive.

<Info>
  **Do not assume the format of IDs or tokens**

  Do not parse an ID or token to extract information from it. Fintoc treats format changes as backwards compatible, so the format can change without a new API version. For example, objects created before `2021-05-05` do not have a prefix on their IDs.
</Info>