ssh-add(1) on macOS
The text 631d12449946, as Mac OS X 10.3.9, Mac OS X 10.3.8, Mac OS X 10.3.7, Mac OS X 10.3.6, Mac OS X 10.3.5, Mac OS X 10.3.4, Mac OS X 10.3.3, Mac OS X 10.3.2, Mac OS X 10.3.1, Mac OS X 10.3 shipped it.
adds RSA or DSA identities to the authentication agent
Flags it lists
-
-D -
-L -
-X -
-c -
-d -
-e -
-l -
-s -
-t -
-x