Thanks for giving us a go, that's really useful feedback. We need you to create an account because there's nothing linking your slack groups. Their API is all about individual groups, and we don't get your email when you authenticate, just your slack handle. There are rumours slack will address this but until then we need your help to tie them all together.
Co-founder of MetaChat here. We’re NLP nerds who have been playing with the Slack API for a while. Lots of people complain about notification overload (e.g. Wednesday's article in The Verge[0]), so we’ve been trying to tackle that with search and summarization.
Feedback welcome! For instance I think the search works quite well for my Slack teams, but maybe you use unusual words that trip up our code and make the results less useful.