Scaling Managed Agents: Decoupling the brain from the hands

What this post added

This post introduces Anthropic's Managed Agents service, a new system designed to scale agent capabilities by decoupling the 'brain' (Claude and its harness) from the 'hands' (sandboxes and tools) and the 'session' log. Key technical contributions include: architectural changes to virtualize agent components into stable interfaces (session, harness, sandbox), addressing 'pet' server infrastructure issues by treating containers as 'cattle' that can be provisioned and replaced independently, implementing robust failure recovery mechanisms for harnesses, enhancing security by preventing direct credential access from sandboxes, and improving performance by reducing time-to-first-token (TTFT) through on-demand container provisioning.