Anyone have a list of Marketo Response Codes and meanings for webhooks?

For reference, he's talking about the code that appears in the screen shot below. From my own digging into this I understand that Marketo uses typical HTTP response codes here, but they also have custom responses. The only example I've been able to find in the Marketo community is that a response code of 1000 means "cannot call webhook in batch campaign". I've personally encountered a 1001 response code, but I can't find any documentation that explains what it means. Like Greg, I'd also like a list of response codes and detailed descriptions of what they mean.

 

We just record what the service we call gives us (except in the special case where you use a webhook somewhere it isn't allowed, like batch campaigns). So, we can't really provide a list- it's what the target webservice uses.

Am I correct in taking your comment to mean any response code outside of the standard HTTP response codes means that the Webhook is being used incorrectly? Presumably, then, there is a list of what you can't do and what responses might appear? Do you know what the 1001 response code means?
I hate to press you on the point, but I'm writing webhook troubleshooting documentation for our internal users as well as our clients. I am not a Marketo expert and have been struggling to find helpful documentation. Any help or links you can provide would be greatly appreciated.

Erik, 

Or do you mean whatever response codes we get back, are from our own server? 

Thanks for your help!
Greg

@Phil, Error Code 1001 indicates that the web service emitted an empty response body. 

Thanks for the heads up. I will add this to the developer documentation.

@Greg, yes, that's exactly what I mean. If we call you and get a 200, we put that in the activity. Same if we get 400, 500, whatever.

@Erik and @Murtza,
Thank you both. This is a very helpful discussion and that document Murtza put together is perfect. Really appreciate this level of support.