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

# Versioning

> How the API changes without breaking your integration.

The current version is **2026-11-01**. Webhook payloads carry it as `api_version`.

These changes can happen at any time, and your code should tolerate them:

* new endpoints;
* new optional request parameters;
* new fields in responses and webhook payloads;
* new values in enums such as `reason.code`, query item `code` and error `code`;
* new event types.

Anything else (removing or renaming a field, changing a type or a status) ships as a new dated
version, announced in the [changelog](https://docs.fastcac.com/changelog.md) in advance.


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