Failed to create bridge sockets on every new task after auto-update to 1.1.2156

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?

After Claude Desktop auto-updated to version 1.1.2156 (4e9bb2, 2026-02-05), Cowork fails on every task — including brand new tasks, not just resumed sessions — with the error:
CLI output was not valid JSON. This may indicate an error during startup. Output: Error: Failed to create bridge sockets after 5 attempts

Cowork was working normally on the previous build the day before.
Environment:

Claude Desktop version: 1.1.2156 (4e9bb2) 2026-02-05T20:04:28.000Z
macOS Sequoia (ARM / Apple Silicon)
socat 1.8.1.0 installed via Homebrew
TMPDIR (exists and writable)

What I've tried (none resolved it):

Installed socat via Homebrew
Cleared all /tmp/claude-* files and directories
Fully quit and reopened Claude Desktop
Restarted Mac
Only started new tasks (no resumes)

Notes:

This was working on the previous build before the auto-update on Feb 5
Appears related to #19503 but that issue describes resume-only failures — this affects all tasks including new ones

What Should Happen?

Starting a new Cowork task should launch successfully without errors, as it did on the previous build.

Error Messages/Logs

CLI output was not valid JSON. This may indicate an error during startup. Output: Error: Failed to create bridge sockets after 5 attempts

Steps to Reproduce

Steps to reproduce:

Open Claude Desktop (version 1.1.2156)
Open Cowork
Start any new task
Error appears immediately

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Desktop version: 1.1.2156 (4e9bb2)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_