When using ssh-agent, it is possible to have the agent request that the user confirms each signing request that comes in. This is enabled with the -c argument to ssh-add(1).

Please implement a similar feature in Seahorse. The lack of this feature makes it unsafe and undesirable to use ssh's authentication agent connection forwarding, as a compromised remote host will result in an attacker being able to sign any number of requests without the user being aware while they are connected.