The Remote Control Service offers an API for querying and connecting to arbitrary FIDL services on the target.

Queries can match an arbitrary number of services on the system, and select will output all of the matches, formatted according to their place in the component topology.

In the special case of a query that uniquely matches a single service, RCS can connect to that service and pass a handle to it to the host for FFX to use. This is how the the plugin system is able to create FIDL proxies using the component selector mapping.

To query for services on a target, write a selector to match the service(s) of interest.