I’ve created a tool that lives on Glitch which lets you fire up a tiny ActivityPub server, create accounts on it, and send arbitrary JSON objects wrapped in Create activities to those accounts. The main use case is for testing novel object payloads or for copying payloads you’ve seen in the wild and rapidly iterating to ensure the compatibility of your own AP implementation.
And since a picture is worth a thousand words:
(I was unsure where to put this announcement since it’s for a debugging tool that I’m releasing today. I picked the ActivityPub s2s tag since this is relevant for s2s developers.)