"The purpose of a system is what it does" :: "The purpose of a protocol is what it _______"?

I work for Ethereum at the Ethereum Foundation.

Blogger at ribbonfarm.com, running summerofprotocols.com, host of /gloom ☀️

then maybe: 

"The purpose of a system is what it does" :: "The ________ of a protocol is what it does"?

One of the interesting ideas (see Olivia essay) from SoP was that protocols do not have purposes. Only functions.

Tend to agree with Venkatesh take.  Though would put  'instructs' personally.

Enables
Organizes
Brings forth from the void
Coordinates