1. A computer-implemented method for providing an invocable composite network service that is based on multiple other invocable constituent network services, the method comprising: receiving an indication of an invocation of a composite network service on behalf of a user that is performed to obtain a capability provided by the composite network service, the composite network service being based on multiple other constituent network services, one or more of the multiple constituent network services each being accessible based on use of a subscription to that constituent network service; determining provision information for the composite network service that includes an order for invoking the multiple constituent network services to provide the composite network service capability, the order being based at least in part on inter-relationships between parameters of the multiple constituent network services that represent related types of information; determining use information for the composite network service that indicates one or more restrictions on use of the composite network service, the restrictions being based at least in part on restrictions on use of the multiple constituent network services; automatically determining whether the indicated restrictions are satisfied by the composite network service invocation, the automatic determining being performed by one or more configured computing systems; and if the indicated restrictions are determined to be satisfied by the composite network service invocation, automatically responding by the one or more configured computing systems to the invocation by, for each of the one or more constituent network services, automatically obtaining a subscription for the user to the constituent network service; invoking the multiple constituent network services in the indicated order to access capabilities of those constituent network services related to the composite network service capability, the invoking of the one or more of the multiple constituent network services being based in part on the obtained subscriptions; and providing response information that is generated based on response information from the invoking of at least some of the multiple constituent network services.