I just use separated ssh-agent with separated keys when I may need to forward the agent. For example, to deploy things to a production host from a build host I

I just use separated ssh-agent with separated keys when I may need to forward the agent. For example, to deploy things to a production host from a build host I login to the build host using the agent with the production key and push things from there. With that, the jump host support and the ability to login with one agent but to forward another I just see no point for what ssh is doing. As they wrote, they want to keep things simple. But this complicates things.