Your watchdog kills the busy agent and trusts the stuck one
A health check that watches whether a long-running agent still exists gets both hard cases wrong: it kills a healthy agent the moment it goes quiet enough to look absent, and it waves through a frozen one whose process is still up. The repair is not a sharper probe but a different signal, the durable trail an agent leaves only by doing the work, which a wedged one stops extending because extending it is the work.