Going through messages in PI using http requests

Hi,

I'm researching for an external tool that will handle PI channels.

I'm aware of the stop, start and status actions that can be used in an http request.

But what if I want more detailed information?

For example, if a channel is in status error, is there an http request to get details about the error?

What about messages? Is there a request I can use to find out what messages came through the channel?

So what else can I get using http requests besides the basic 3 actions?

What about RFC calls? Can they be used to get more information on channels/errors/messages?

Someone has a guide, about the http calls/RFC that can be used.

Thanks!