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Claude Cowork moves inference and isolated session VMs to the cloud

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The new Cowork design runs inference and a separate sandbox VM for each session in the cloud, while the desktop app handles local file access. This trades local battery and performance costs for a cloud-hosted agent architecture with per-session isolation.

What: The new Claude Cowork runs model inference and its virtual machine in the cloud instead of running the VM on the user's computer.
How: Each session gets an isolated sandbox; when it needs a local file, the desktop app handles the file-access tool call.
Why it matters: Moving the VM to the cloud avoids its local disk, battery, and performance costs and lets work continue when a laptop is closed.

Model tool calls run in a cloud VM, which requests local files through the desktop app. Sketched from the article's own text.

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