My only wishlist item for `ssh-agent` that would make all use of the agent safer, or nearly as safe as a hardware key, is that it had the option for an interactive confirmation dialog or mechanism for the user to confirm the source, destination, key, and client making the signing request. This is how most crypto wallets work, and given that the SSH private key never leaves the original host's agent's memory, a confirmation on use mechanism would alleviate most remaining forwarded agent hijacking concerns.