What is FRAPI?
FRAPI is the FusionReactor API and it gives you the ability to access FusionReactor functionality from directly within your ColdFusion MX pages.
What can I do with FRAPI?
With FRAPI you can make your pages aware of what else is currently running on your server. You can change FusionReactor settings and you can set user trace markers.
What is a User Trace Marker?
A user trace marker can be used for many purposes. For example, you could use it to debug a page and work out where the flow of execution goes, or you could surround critical sections of your code and work out exactly how long they are taking to execute. The main advantage of this mechanism is that you can implement it without having to display any debug information to end users or having to write to hard-to-read debug files on your server.

