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

# API enhancements

> New external_id user field introduced.

<div className="release-meta">
  <span className="release-date">June 2, 2023</span>
  <span className="release-tag" data-changelog-tag="api">API</span>
</div>

<img src="https://mintcdn.com/argyle/spW0uZwUC4bDyMgL/images/changelog-generic/api.png?fit=max&auto=format&n=spW0uZwUC4bDyMgL&q=85&s=1537fc09ccdfb211eeafbc1178e91f0b" alt="API update illustration" width="1030" height="290" data-path="images/changelog-generic/api.png" />

You can now attach your own identifier to users via the new `external_id` field when [creating](https://argyle.com/docs/api-reference/users#create) or [updating](https://argyle.com/docs/api-reference/users#update) users via the API.

* The `external_id` field supports up to 100 characters and can be used as a filter when [listing users](https://argyle.com/docs/api-reference/users#list).
* Multiple users can have the same `external_id` value.

Visit our [Users API Documentation](https://argyle.com/docs/api-reference/users) for more information.