[BUG] Claude Desktop app stuck on "Shimmying..." indefinitely - not executing any actions

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?

When sending a message in the Claude Desktop app (Windows 10), the app gets stuck on "Shimmying..." indefinitely. It never starts executing any tools or producing output. This has been happening consistently for the past 2 weeks.

The issue occurs regardless of the prompt content — simple or complex messages all get stuck at the same "Shimmying..." loading state. Stopping and resending sometimes works, but the problem keeps recurring.

Platform: Windows 10 Home (10.0.19045)
App: Claude Desktop (latest version)
Model: Opus 4.6 (1M context)

What Should Happen?

The app should proceed past the "Shimmying..." state and begin executing the request normally — calling tools, generating output, or responding to the user. It should not hang indefinitely on the loading animation.

Error Messages/Logs

Steps to Reproduce

1. Open Claude Desktop app on Windows 10
2. Send any message (simple or complex)
3. The app shows "Shimmying..." loading animation
4. It stays stuck on "Shimmying..." indefinitely — no tools are called, no output is generated
5. Clicking Stop and resending sometimes works, but the issue recurs frequently

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Desktop app (latest version, Windows)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_