Constitutional rules-in-use determine who "must, may, or must not participate in making collective choices." In other words, these govern a kind of citizenship of the particular commons.
With regard to who may or may not participate in this commons, I don't believe that there is yet any formal charter. After all, I was admitted to play around in this don.tries.fed.wiki by virtue of pestering Ward Cunnigham and having him patiently and most helpfully get me started. If the community starts to grow, how will these determinations be made in the future? My impression (and I am still speaking as a total novice here) is that within one's own domain it is possible to admit others, but their participation will be limited to the scope allowed the person permitting access.
I hope someone will advise on this. I don't want to make guesses.