In order to perform system-capability testing, an application in an application layer may provide predefined system capabilities and/or requirements of or associated with the application to a communication plugin in a data-link layer, such as availability of communication via a network and/or a latency of the network less than a predefined value. In response, the communication plugin may determine feedback information that specifies whether the predefined system capabilities are available and whether the predefined requirements are satisfied. Then, the communication plugin may provide the feedback information to the application. When the feedback information indicates that a system capability is unavailable, remedial action may be performed. For example, the remedial action may include updating a version of the application, updating a version of the communication plugin, and/or updating a path to a location in a network.