It’s possible to both query (GET) or create (POST) a post on a users timeline/feed. But as far as I can see, the documentation only lists the possible fields you get back when querying – not which of those fields it’s possible to set when doing a POST.
Can anybody link to a complete list of fields that I can set during a POST to https://graph.facebook.com/arjun/feed
See the
postsconnection on theUserobject. Required is onlymessageorlink.