This is a Metadata Agent for downloaded YouTube videos. It works by looking up metadata on YouTube using the YouTube video id. It is important to have this id in the filename, otherwise this agent can't do the lookup. You can change the way the id is found in your filenames (through the Agent's preferences). This value is a regular expression and requires 1 named group called id.
The default value is: \[(?P
This will find the YouTube id in names, like for example:
Person Of Interest Soundtrack - John Reese Themes (Compilation) [OR5EnqdnwK0].mp4
Download and source
See the How do I manually install a channel? support article.