[BUG] Agents always fail to work on Windows 11

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?

● Explore(Investigate library rebuild issue)
  ⎿  Done (0 tool uses · 0 tokens · 0s)

● Explore(Investigate engine build process)
  ⎿  Done (0 tool uses · 0 tokens · 0s)

This has been ongoing for months now. Agents are a huge part of Claude Code. It's significantly better when agents work when I'm using Linux or MacOS.

What Should Happen?

Agents should be able to do whatever task they've been tasked with.

Error Messages/Logs

Claude just always states there's an API error with agents and tries to do the tasks manually.

Steps to Reproduce

1. Tell Claude Code to spawn an agent to do X.
2. Claude spawns an agent to do X.
3. Immediately fails with an API error.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.15

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

These issues are always getting closed out as duplicates, but I cannot find any active ones.