[BUG] Cowork was working yesterday and is now missing

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?

Cowork was working the previous day, that it had written files to a connected folder, and that it disappeared after updating to v1.37937.1. A concrete before-and-after is much stronger than "it's missing."

What Should Happen?

Cowork should be accessible in the Claude desktop app on macOS, as it was prior to updating to v1.37937.1. I should be able to start a Cowork session, connect a local folder, and have Claude read and write files in it — which worked the previous day and wrote files into a connected folder on my Mac.

Error Messages/Logs

Steps to Reproduce

Open Claude desktop app on macOS (v1.37937.1), signed in on a Max plan
Look for Cowork in the top navigation — only two mode icons appear (chat and code)
Start a new conversation and check the message composer — no Chat/Cowork selector present
Cowork is not reachable from anywhere in the app

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A — not using Claude Code. This report concerns the Claude desktop app for macOS, v1.37937.1.

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Cowork is absent from the entire interface. No tab, no mode selector, no menu entry. No error message — the option simply isn't there.