Anthropic Cowork feature creates 10GB VM bundle on macOS without warning

Description

After using the cowork feature, Claude Desktop becomes extremely slow - slow startup, UI lag, and slow responses. Performance degrades over time even during a single session.

Investigation

VM Bundle (10GB)

The cowork feature creates a VM bundle at:

~/Library/Application Support/Claude/vm_bundles/claudevm.bundle/rootfs.img

This file grows to 10GB and is never cleaned up. It regenerates quickly after deletion (deleted one day, back to 10GB the next).

Cleanup Test Results

Deleted vm_bundles, Cache, and Code Cache directories (reduced from 11GB to 639MB).

Result: ~75% faster immediately after cleanup on tasks that previously failed/hung.

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