[BUG] Claude Cowork keeps crashing

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Cowork crashes with this in the logs (see below).

Did not use claude cowork for a while, I do not know when this behavior started. Reinstalled fresh and followed all claude chat advices (deleting a couple of files), to no avail.

<img width="805" height="339" alt="Image" src="https://github.com/user-attachments/assets/93fc7a02-df3d-4e7b-af7e-33922b3129cb" />

Maybe duplicate of https://github.com/anthropics/claude-code/issues/26945 (but this is already closed due to inactivity)

What Should Happen?

Claude cowork should work.

Error Messages/Logs

2026-07-06 07:51:15 [info] [Lifecycle] Session local_624ecaf3-691f-42c6-a955-9444284f0eb6: initializing → running
2026-07-06 07:51:15 [info] [FileWatching] Starting file watcher for session local_624ecaf3-691f-42c6-a955-9444284f0eb6: /Users/carstengraef/Library/Application Support/Claude/local-agent-mode-sessions/f0ec1bf9-3018-46f4-994c-159447dfc110/a889aada-7fc2-4eff-9731-8687b61baecb/local_624ecaf3-691f-42c6-a955-9444284f0eb6/outputs
2026-07-06 07:51:15 [info] [FileSystemWatcher] Started watching /Users/carstengraef/Library/Application Support/Claude/local-agent-mode-sessions/f0ec1bf9-3018-46f4-994c-159447dfc110/a889aada-7fc2-4eff-9731-8687b61baecb/local_624ecaf3-691f-42c6-a955-9444284f0eb6/outputs for session local_624ecaf3-691f-42c6-a955-9444284f0eb6
2026-07-06 07:51:15 [error] Sentry caught: {
  eventId: '5042b9016b81459080e51ba9cc8dcb97',
  type: 'Error',
  value: 'write EPIPE',
  stack: 'Error: write EPIPE\n' +
    '    at WriteWrap.onWriteComplete [as oncomplete] (node:internal/stream_base_commons:87:19)'
}
2026-07-06 07:51:15 [warn] [HostLoop] cli.js stderr: Failed to spawn process: Malformed Mach-o file
2026-07-06 07:51:15 [error] Session local_624ecaf3-691f-42c6-a955-9444284f0eb6 query error: Claude Code process exited with code 127 { stack: 'Error: Claude Code process exited with code 127\n    at C4i.getProcessExitError (/Applications/Claude.app/Contents/Resources/app.asar/.vite/build/index.js:890:8373)\n    at ChildProcess.r (/Applications/Claude.app/Contents/Resources/app.asar/.vite/build/index.js:890:11741)\n    at Object.onceWrapper (node:events:631:26)\n    at ChildProcess.emit (node:events:521:24)\n    at ChildProcess._handle.onexit (node:internal/child_process:295:12)' }
2026-07-06 07:51:15 [info] [Lifecycle] Session local_624ecaf3-691f-42c6-a955-9444284f0eb6: running → idle
2026-07-06 07:51:15 [info] [FileWatching] Stopping file watcher for session local_624ecaf3-691f-42c6-a955-9444284f0eb6
2026-07-06 07:51:15 [info] [FileSystemWatcher] Stopped watching for session local_624ecaf3-691f-42c6-a955-9444284f0eb6
2026-07-06 07:51:15 [info] [CycleHealth] Unhealthy cycle: {
  session_id: 'local_624ecaf3-691f-42c6-a955-9444284f0eb6',
  scheduled_task_id: null,
  variant_key: 'pewter',
  session_built_prompt: true,
  space_id: undefined,
  session_type: undefined,
  parent_session_id: undefined,
  host_loop_mode: true,
  vm_instance_id: '1458272a-086f-435c-afd2-dcdef6c1f691',
  model: 'claude-sonnet-5',
  cli_session_id: null,
  user_message_uuid: 'fb7df9c1-bae0-47af-b334-ea5ce0f672ac',
  cycle_health: 'unhealthy',
  had_first_response: false,
  seconds_to_outcome: 2,
  is_resume: false,
  unhealthy_reason: 'system_error',
  error_message: 'Claude Code process exited with code 127',
  error_category: 'process_crashed',
  transcript_size_bytes: undefined
}
2026-07-06 07:51:15 [error] Sentry caught: {
  eventId: 'a9f96c6b074f44b4ad164370f58085ed',
  type: 'Error',
  value: 'Claude Code process exited with code 127',
  stack: 'Error: Claude Code process exited with code 127\n' +
    '    at C4i.getProcessExitError (app:///.vite/build/index.js:890:8373)\n' +
    '    at ChildProcess.r (app:///.vite/build/index.js:890:11741)\n' +
    '    at Object.onceWrapper (node:events:631:26)\n' +
    '    at ChildProcess.emit (node:events:521:24)\n' +
    '    at ChildProcess._handle.onexit (node:internal/child_process:295:12)'
}

Steps to Reproduce

1. open claude desktop
2. use cowork tab
3. ask anything

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.18286.0 (259c3f) 2026-07-02T07:11:03.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_