Claude Cowork moves its virtual machine to the cloud
What happened
According to Simon Willison on October 6, citing Anthropic's Felix Rieseberg, the older version of Claude Cowork ran in a hybrid way: model inference happened in the cloud, while tool calls ran in a virtual machine on the user's computer. The new version moves both model inference and the virtual machine to the cloud, changing where the tool execution environment sits. In the new version, each session gets its own sandbox and sessions do not share state; when files on the user's device need to be accessed, those tool calls are still executed by the desktop app.
Written by AI from the coverage · updated 1 hour ago
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- Simon WillisonPickFelix Rieseberg explains Cowork's move of its virtual machine to the cloud
In the new version of Cowork, both model inference and the virtual machine run in the cloud. The old version ran inference in the cloud but executed tool calls in a virtual machine on the user's computer. Simon Willison cites Anthropic's Felix Rieseberg saying each session gets its own sandbox with no shared state, and the desktop app handles tool calls when device files are needed.
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