Windows: PowerShell -Include + Remove-Item wiped git repo during "clean junk files"

Description

Summary

On 2026-09-11, OpenCode (model grok-4.6 / xai) deleted almost the entire working tree and .git/objects while handling a request to clean invalid/expired files. This was a permanent Remove-Item -Force, not Recycle Bin.

Environment

• OS: Windows 10/11, PowerShell 5.1
• Product: OpenCode
• Model: xai/grok-4.6
• Repo: C:\Work\3.Code\box_v1.2(ESP32S3+GD32F103)
• Cleanup session: ses_f70811a37ffexT0bYeE2j947UM (started ~16:04 CST)
• Prior work session same afternoon: ses_f70cec837ffeiBLxux59UMLmnd (14:39–15:52 CST)

What I asked

Clean invalid and expired files in the current folder (temp, caches, stale backups). I did not ask to delete source or .git.

What went wrong

The agent enumerated files with:

Get-ChildItem -LiteralPath $root -Recurse -Force -File -Include '*.pyc','*.pyo'

On PowerShell 5.1, -Include with -LiteralPath does not filter by extension. It returned nearly every file, including .git objects. Those paths were passed to Remove-Item -LiteralPath ... -Recurse -Force.

Git objects are content-addressed. After deletion they were not in Recycle Bin and could not be undeleted.

Impact

Before deletion, git status showed master 132 commits ahead of origin/master, plus uncommitted afternoon work.

After deletion:

• working tree files gone
• .git/HEAD gone
• .git/objects file count = 0

Partial recovery (not a fix)

• Source tree restored from sibling git worktree box_v1.2(ESP32S3+GD32F103)-wall (last write 14:04 CST)
• .git restored from an old Recycle Bin backup (HEAD 38ad35f, 2026-08-22)
• Afternoon edits restored from OpenCode snapshot pack + session DB blobs/patches

Still lost:

• history of ~132 local unpushed commits
• any master changes after 14:04 that were not in the afternoon OpenCode session
• firmware/esp32/build cache

Expected behavior

• Never recursively delete from repo root without an explicit file list and user confirm
• Never touch .git/
• Do not use PowerShell -Include as a file-type filter
• Prefer git clean dry-run or an allowlist of gitignored paths (tmp/, __pycache__/, *.pyc)

Request

Treat this as a safety defect: destructive filesystem ops on Windows need a deny-list for .git, a confirm step, and a filter that actually works on PowerShell 5.1.

Plugins

No response

OpenCode version

No response

Steps to reproduce

No response

Screenshot and/or share link

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Operating System

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Terminal

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