[BUG] Windows: PowerShell tool returns Exit 1 silently — pwsh works fine outside CC[Bug] Windows: PowerShell tool returns Exit 1 silently — pwsh works fine outside CC

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?

Description

On Claude Code Desktop 2.1.142 (Windows 11), every invocation of the native PowerShell tool returns Exit code 1 with no output and no error message, even for trivial commands like "hello" or Write-Output "test".

The bug is persistent across:

• Closing and reopening Claude Code Desktop
• Full Windows reboot

The Bash tool works normally throughout, and PowerShell itself is fully functional when invoked from the Bash tool (pwsh -Command "..." or powershell -Command "...").

Environment

• OS: Windows 11 (build 26100.8457)
• Claude Code Desktop version: 2.1.142 (auto-updated, latest available)
• CLI npm version: 2.1.138 (@anthropic-ai/claude-code published 2.1.144)
• pwsh version: 7.6.1 (installed via Microsoft Store — Microsoft.PowerShell_7.6.1.0_x64__8wekyb3d8bbwe)
• Windows PowerShell version: 5.1.26100.8457
• Session entrypoint (from ~/.claude/sessions/<pid>.json): claude-desktop

Steps to reproduce

1. Open Claude Code Desktop on Windows 11
2. Invoke the PowerShell tool with any command, e.g.:

```powershell
"hello"

What Should Happen?

Result: Exit code 1, no stdout, no stderr
Expected behavior
Output of the command (e.g. hello).

Actual behavior
Exit code 1, no output at all. The error is silent — nothing surfaces to the user beyond the bare exit code.

Error Messages/Logs

Steps to Reproduce

Workaround (validated)
Invoking PowerShell through the Bash tool works perfectly:

pwsh -Command "Write-Output 'test'" # → test
pwsh -NonInteractive -NoProfile -Command "..." # → OK
powershell -Command "Get-Service ssh-agent" # → OK

So the issue is specifically with how claude.exe invokes pwsh internally, not with PowerShell itself.

Investigation done
pwsh.exe and powershell.exe are both accessible and functional from Bash tool
All PowerShell $PROFILE.* paths return Test-Path = False (no profiles installed, not the cause)
PATH includes both /c/WINDOWS/System32/WindowsPowerShell/v1.0 and /c/Users/<user>/AppData/Local/Microsoft/WindowsApps
~/.claude/shell-snapshots/ contains only snapshot-bash-*.sh files — no PowerShell snapshot is ever generated, even after many tool invocations
The cache directory ~/AppData/Local/Microsoft/PowerShell/7.6.1/ contains a StartupProfileData-NonInteractive file that is regenerated normally on direct pwsh invocations from Bash
winget upgrade Microsoft.PowerShell reports "no newer version available"
pwsh works in all modes when invoked from Bash: -NoProfile, -NonInteractive, -NoProfile -NonInteractive, with .exe or via execution alias
Hypothesis
Claude Code Desktop on Windows appears to fail at creating its shell-snapshot for PowerShell at session initialization. The absence of any snapshot-pwsh-*.ps1 (or similar) in ~/.claude/shell-snapshots/ suggests the snapshot generation crashes silently, and all subsequent PowerShell tool invocations inherit that broken state.

Impact
Low/medium. The Bash → pwsh workaround is trivial. But:

Users not aware of the workaround will think PowerShell is broken on their system
Verbose syntax overhead (pwsh -Command "..." instead of native PowerShell tool)
Project-level settings.json permissions for PowerShell(...) patterns become useless until the bug is fixed

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

CC Desktop = 2.1.142

Claude Code Version

2.1.138

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_