DMM answers as a Newznab indexer, so Prowlarr, Sonarr and Radarr can search it like any other and grab what they find.
Needs a DMM API key, which comes with a sponsorship. Get it on gatekeeper, then paste it in Settings. Already sponsoring on another machine? Same key.
Prowlarr: Settings → Indexers → + → Newznab (the generic one). Sonarr and Radarr take the same three values under Settings → Indexers → + → Newznab if you would rather skip Prowlarr.
https://debridmediamanager.com/api/newznab/apiyour DMM API key from gatekeepert=searcht=tvsearcht=movieAn id search that comes back empty is not proof the release is missing — fall back to a free-text query before blaming the indexer.
Anything outside these is not served, so leave the rest unticked in Prowlarr — mapping a category DMM does not advertise just produces empty searches.
They are counted against your DMM API key, not your IP, so several *arr instances behind one key share the same budget. A search storm is the usual way to hit them: cap Prowlarr's RSS sync interval rather than letting a full library search run unthrottled.
Prowlarr only finds releases; something has to fetch them. Pair this with DMM as a SABnzbd download client, and a grab is pulled off Usenet, rebuilt as a torrent and added to your own Real-Debrid account.