globus_gram_protocol_definition(3) on Linux
The text bf0596202fa7, as Debian 10 (Buster) shipped it.
GRAM Protocol Definition The GRAM Protocol is used to handle communication between the Gatekeeper, Job Manager, and GRAM Clients. The protocol is based on a subset of the HTTP/1.1 protocol, with a small set of message types and responses sent as the body of the HTTP requests and responses. This document describes GRAM Protocol version 2.