The Searchdomain-AvailablePackages interface includes various settings.

Table: Searchdomain-AvailablePackages

filterstring  The filter input to limit the returned packages.
tagsRepoOrViewNameyes Packages with any of these tags will be included. No filtering on tags. The type, RepoOrViewName is a scalar.
categories()[string]): [PackageRegistrySearchResultItem]  Packages with any of these categories will be included (see PackageRegistrySearchResultItem Table).

[a] Some arguments may be required, as indicated in this column. For some fields, this column indicates that a result will always be returned for it.