With the release of CMS 2019.11 and it's new probe setup capability, a rich set of REST APIs have also been released that allow for control of the list of credentials managed by the probe, and management of the IP ranges.
The full list of REST APIs available with CMS 2019.11, including those specific to the Data Flow Management configuration process, are documented here - https://docs.microfocus.com/UCMDB/2019.11/ucmdb-docs/docs/eng/APIs/UCMDB_RestAPI/index.html
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As we add new functionality to the new CMS UI, we also expose the corresponding RESET APIs to perform the same function. The ability to manage discovery credentials via REST API is high on our list.