According to the metadata search integration, The search process seems to take place in the Smart Client Plugin. But I want to do this in my application using MIP components, No Plugins. Is it possible?
A SearchAgent is a Smart Client plugin, this plugin can communicate with an external application or service and in that way you can use if you have external metadata or processing.
If you are not talking about a SearchAgent, but rather wants to read metadata from XProtect this is possible. In that case maybe the Metadata Playback Viewer sample is a good place to start.
These are two very different ideas, it might be that your solution needs both, it might be that none of them fit and you had a third scenario in mind, if that is the case please elaborate on the use case.