Hi Corbin,

For future, please use the Support Portal for Atlas in lieu of the public forums.

The URL you're looking at is outdated. That particular doc is for LabKey 9.3, not the latest version.

And the endpoint to create containers does exist here:

https://www.labkey.org/download/clientapi_docs/java-api/org/labkey/remoteapi/security/CreateContainerCommand.html

Regards,

Jon