A number of plugins do not really fit into the category of local checks versus remote checks because they themselves do not detect operating states but manipulate the results of other checks or summarize them into new results. These include the plugin
check_dummy, which always returns a fixed result in order to create a well-defined environment for test scenarios.
negate (which negates the return value) and
urlize (which adds a hyperlink to the text output) manipulate the outputs. Summarizing and processing check results is the task of
check_cluster only combines and evaluates existing states,
check_multi calls the specified plugins itself and combines their results.