I couldn't find specific documentation on a REST API call to find users that are not assigned to any workspace. Typically, workspace management involves adding or inviting users to workspaces, as detailed in the
workspaces documentation. There might not be an explicit mention of an API endpoint for unassigned users because this seems to be a less common use case.
However, for Workspace Owners, the
Prefect documentation provides insights into managing members and service accounts for workspaces. If there is functionality for listing members of a workspace, you may need to pull lists of all users and all workspace members and then programmatically determine the difference.
Regarding Prefect Cloud API, there are ways to manage users, service accounts, and API keys, as indicated by the
API keys documentation, but it doesn't detail an API for identifying unassigned users.
You might want to check the
GitHub repository issues or raise a question there if you require more specific API details or if this feature is not currently supported.