To display keys added to ssh-agent using ssh-add, run the following commands.
Lists fingerprints of all identities currently represented by the agent
$ ssh-add -l 2048 SHA256:LCKfvuHHXc675Vn2l7K2+6rcXjnjm9Ay/y5icAe2ORI /Users/user1/.ssh/id_rsa (RSA)
Lists public key parameters of all identities currently represented by the agent
$ ssh-add -L ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDH4ZWhgBnDmEJfqTt/I9/2GFLXmvhqvA0PoF7I2iFk6Ph+3zQXNollZ4XKGqtKNBbDRtQsODjOQz6eQfHslRg0g217xt+CGY+1vT2HMuOjPxG/LX0KlL2c1B/xSSFpPxfDU1i/aG0sfYYwoFLIg/fCELBGDo4XGD1QSt86xaLhg1jpw6PSOFG8Dn/gEh7CsFEO09/z4ABHpI0/xPzJh5xjL8/+QOKYGpY5yMxnIk+6+zaVS9LLftS55xgSoBvJOOm11FvX7A5VGrOAtSlq+4j7oyu4t+SK7vKoTrhUjWg+xEAnl0V3/B5YtY4Ud5ia5glUZRIOYWOcKsm2rT/adv9Z /Users/user1/.ssh/id_rsa