Claude Managed Agents' durable harness can return initial tokens quickly and preserve the agent when its execution sandbox terminates.

“The part of the reason why we did this was for, like, latency and reliability and these sorts of things, right?”

“Like, if the harness is just running on a durable server and it's only spawning a sandbox or a container to execute when it needs it, that means we can get you tokens back really quickly on your initial request.”

“It means that your sandbox can die, but, like, your whole agent doesn't die because the harness is durable and over here and the har- you know, the agent's storing state separately also.”