NSClient++

NSClient++ is specially designed to be a Windows service that allows performance metrics to be gathered by Nagios/Icinga. While specifically built for these services, the developer claims that you can use the app in numerous other scenarios that involve receiving and distributing check metrics. The standalone app is meaningless by itself, but it supports a vast array of protocols and hence allow it to be used with various monitoring solutions.
The idea behind the monitoring daemon can fulfill three main functions, the most important one being that it allows a remote machine – or server – to request commands to be run on the machine and return its status. At the same time, the application can submit the same results to a remote monitoring server, take action and perform various tasks.
It is worth mentioning that the tool is open ended so you can customize it according to your needs and preferences. You can extend its functionality using external scripts that respond to queries and that can be executed by the operating system, whereas the results are return as-is. In addition to ExternalScripts, the app can also be used with LuaScripts and PythonScripts, which are both internal scripts for performing various tasks. Lastly, you can use modules and .NET modules, the later having the role of permitting you to write components on top of the large dot-net ecosystems.