To me it seems specific enough.
Genesis 17:9-11 And God said unto Abraham, Thou shalt keep my covenant therefore, thou, and thy seed after thee in their generations.
This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised.
And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.
Circumcise just means to cut around (although we associate it with circumcision of the foreskin, as that is the context it is primarily used in). And foreskin is the unneeded skin barrier covering the male member at birth. When the flesh of the foreskin is circumcised, the male member is freed from the excess skin (also making it easier to clean, more difficult for bacteria to build up, and other hygiene benefits). Or were you referring to what tools were to be used, what the ceremony should entail, or something like that?
I think this is the reason for the Abrahamic covenant. The Abrahamic covenant was for all of Abraham's descendants (i.e. prior to the 10 commandments), whereas the Sinaitic covenant was for the Israelites who covenanted with God at Sinai (already circumcised in order to remain Israelites).