I’m excited, my pre-ordered Argon and Xenon gear should ship this week! Now I need to get my debugging tools in order! I’m coming in a bit late to the game, and I’m hoping some of you pioneers (ScruffR?) are here on the forums and will share some of your clues with us. 
Is it possible, from my sketch, to find out some level of detail of the mesh network, as seen by my node? I presume that my node knows about all of the nodes currently in the mesh, denoting which are Gateways, but how much of that is available to my sketch? (I’m a network builder, and I go back to X.25 running routers with leased lines, and AX.25. I’m looking for ways to know when nodes have dropped off the RF Mesh network, and I expect that there is some latency between when a node joins and/or dies, and when I could detect that from changes in the mesh map. But, as I’m learning, I’m looking for any debugging info I can collect.
If it’s not possible from the sketch, what tools are you using to look at the bare RF network packets, to look at things like node addresses and their mesh-map broadcasts? I’m comfortable with WireShark, but I haven’t tried SDR (which of them work at 2.4 GHz, or do I need a pre-scaler with a lower-frequency SDR?), and I see references to ZigBee Mesh USB dongles (but I understand that Particle isn’t really ZigBee…), so should a ZigBee USB dongle help? Or is the “right answer” a RAspberry Pi with some USB interface? Or can I use a Xenon, with a USB cable and a software update, to be a packet monitor for my Particle Mesh?
If I can’t get “local” clues from my nodes or an RF network monitor, can I get that map data from the Particle Cloud, maybe with an API call or two?
Thanks for sharing your thoughts, and best regards, Zonker