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NOPE
Low reported severity Media Coverage

Claude Code: a sub-agent launched to rebuild a test mirror deleted about 48,000 live project files and the Git object store in 103 seconds by following Windows directory junctions, according to the user's Reddit account and the agent's own report posted on 20 September 2026

On 20 September 2026 (UTC; late on 19 September in US Eastern time) a Reddit user who says they work in finance and are not a developer posted in r/ClaudeAI that Claude Code had deleted about 48,000 files, and later posted their instructions and the agent's report. They had authorised Claude Code to carry out a batch of repairs to their software for back-testing options-trading engines 'on isolated copies'. The agent's report says it launched sub-agents; one, rebuilding a test mirror, wrote a remover for an old mirror that held 7,332 files and 614 Windows directory junctions pointing into the live project tree. Because the remover did not treat the junctions as links, it deleted about 48,218 live files between 10:10:31 and 10:12:14 PM ET and emptied the Git repository's objects, refs and logs, so Git could not restore anything. The agent opened its report with 'stop and read this. I broke something.' The user said they would try Windows shadow copies and otherwise their iDrive backups; whether the files were recovered is not reported. The account has not been independently verified.

AI system
Claude Code
Anthropic (Claude Code)
Occurred
19 Sept 2026
Reported
20 September 2026
Event location
Unknown
What the AI did
Acted on the person’s behalf
Reported harm
Other Material Harm
Whose AI use
Their own AI use
Setting
Everyday life
Evidence
AI involvement reported · Causal attribution supported · 5 sources, 1 underlying account
4 claims: 4 reported. 4 open questions
People reported harmed
1 person

AI system as recorded: Claude Code (Anthropic) running a multi-agent repair workflow on a Windows machine; the underlying model version is not stated

What Happened

The Reddit post 'Code just deleted 48k files. This can't be real.' was created in r/ClaudeAI at 03:00 UTC on 20 September 2026 (arctic_shift record) and later removed; its body was not recoverable. In a comment the same user posted the prompt they had given and Claude Code's reply. The prompt authorised fifteen repairs to their options back-testing code: 'This is explicit authorization to build, correct and test them on isolated copies.' One item asked it to 'rebuild the mirror against current files'. Claude Code reported that it launched eleven boxes of work, each checked by an adversarial verifier, and that the verifier for the mirror job reported writes outside its box. It then wrote: 'stop and read this. I broke something. An agent I launched deleted about 48,000 live files from the Dashboard tree between 10:10:31 and 10:12:14 PM ET tonight, and destroyed the git object store.' It explained that build_mirror.py could not refresh in place, so the sub-agent wrote a remover for the old mirror in a temporary folder; that mirror held 7,332 real files and 614 Windows directory junctions pointing into the live tree, and the remover's os.walk(followlinks=False) did not stop at the junctions because islink() is False for junctions on Windows. The remover's guard only skipped files directly in a junction's root. The report counts 728 emptied directories and says Git 'cannot restore anything'; the report lists the root files, the remaining documentation and backup files, and the folders outside the project tree as intact, although 78 directories under the documentation folder were emptied. Cyber Security News computes 48,218 deleted live files from the log (55,550 files removed less the 7,332 intended). The date is taken as 19 September 2026: the agent said 'tonight' of a 10:10 PM ET deletion, the post was created about 11:00 PM ET that night, and a file the agent created in the same session is dated 2026-09-19. In another comment the user wrote that they are 'in finance, not a developer' and would try shadow copies, then their iDrive backups. According to Yahoo Tech, an archived copy of the post acknowledged that they were not properly using GitHub or another method for immediate corrections.

Reported harm

About 48,218 live project files and the project's Git history were deleted by a sub-agent during an authorised repair job, according to the user and the agent's own report posted on Reddit; recovery was being attempted and its outcome is unknown.

Outcome

Unknown

No company response is reported. The user said they would attempt recovery through Windows shadow copies and otherwise their iDrive backups; the result is not reported. The Reddit post drew more than 1,300 comments (arctic_shift count 1,375) before it was removed; Cyber Security News (21 September 2026), Yahoo Tech (25 September, a Future syndication) and TechRadar (27 September) covered it.

What remains unknown

  • Whether the files were recovered from shadow copies or backups, and how much work was lost.
  • The Claude Code version, model and permission mode used.
  • The removed post's full text (only quoted fragments and the poster's comments were read).
  • The user's location.

What the evidence supports

AI involvement: reported. The user posted their prompt and Claude Code's own report, in which the agent says 'An agent I launched deleted about 48,000 live files' and explains the junction-following remover a sub-agent wrote (Reddit comment via the thread RSS). The deletion was an action the agent took on the user's behalf under a broad authorisation to work on isolated copies. No logs were published, and the account is not independently verified (Cyber Security News notes the same).

4 claims: 4 reported. What the statuses mean

Reported According to Claude Code's report as posted by the user, a sub-agent it launched to rebuild a test mirror wrote a remover for an old mirror containing 7,332 files and 614 Windows directory junctions into the live tree; the remover followed the junctions and deleted about 48,000 live files between 10:10:31 and 10:12:14 PM ET and destroyed the Git object store.

Causal attribution. The agent's own report as posted by the user; logs were not published and no independent forensic account exists.

  • reddit.com(opens in new tab) supports · English
    'An agent I launched deleted about 48,000 live files from the Dashboard tree between 10:10:31 and 10:12:14 PM ET tonight, and destroyed the git object store.'; 'That mirror is 7,332 real files plus 614 Windows directory junctions pointing into the live tree.'; 'Git cannot restore anything.'
  • cybersecuritynews.com(opens in new tab) supports · English
    'After subtracting the 7,332 intended mirror files, the reviewer calculated 48,218 deleted live files.'
Reported The user had authorised the agent to build, correct and test repairs on isolated copies, including rebuilding the mirror.

Causal attribution. The user's own prompt as they posted it.

  • reddit.com(opens in new tab) supports · English
    'This is explicit authorization to build, correct and test them on isolated copies.'; 'rebuild the mirror against current files.'
Reported The agent opened its report with 'stop and read this. I broke something.'

Causal attribution. Agent output as posted by the user.

Reported The user said they work in finance rather than as a developer and would try Windows shadow copies and otherwise their iDrive backups; according to Yahoo Tech, the archived post said they had not been properly using GitHub or another method for immediate corrections.

Causal attribution. The user's own statements.

  • reddit.com(opens in new tab) supports · English
    'I'm in finance, not a developer.'; 'Hoping for good luck with the shadow copy. If not, I will use my idrive backups.'
  • tech.yahoo.com(opens in new tab) supports · English
    'I was not properly using GitHub or another method for immediate corrections, even though it should have been branching.'

Sources

5 sources inspected, from 1 underlying account. Sources that repeat one account do not corroborate each other.

How the sources were read, and where the events happened

Read on 2026-09-28 from the thread's Reddit RSS feed (comment by the original poster, 20 September 2026, 13:18 UTC): their prompt and Claude Code's report. The post itself was removed and its body could not be read; post metadata from arctic_shift. Applies to s1.

Read on 2026-09-28 from the thread's Reddit RSS feed (comment by the original poster, 20 September 2026, 14:05 UTC). Applies to s2.

Read live on 2026-09-28 (Cyber Security News, 21 September 2026). Relays the Reddit post and the attached verifier report. Applies to s3.

Read live on 2026-09-28 (Yahoo Tech, Future syndication, 25 September 2026). Quotes an archived copy of the removed post. Applies to s4.

Read live on 2026-09-28 (TechRadar, 27 September 2026). Relays the Reddit post and its comments. Applies to s5.

Event countries: Unknown. Affected-person countries: Unknown. Court countries: Unknown.

The account gives times in ET but states no location for the user; no country is recorded. No court proceeding.

Reviewed for publication 2026-09-28: Published under the 2026-09-15 charter as a core acted_on_behalf case from a first-person public forum account: the user posted their prompt and the coding agent's own report of deleting about 48,000 live files during an authorised job. Unverified beyond the poster's account and the agent's report; recovery unknown. The user is not named.

People described

An individual Reddit user who says they work in finance and was building their own options back-testing software (not named)

People reported harmed in this case

1 person

1 AI participant · 0 other people harmed

One person, the user whose files were deleted (their Reddit account). Exact 1.

Counted once within this case. The same person may appear in other cases. This count does not establish AI causation.

Tags

#claude-code#anthropic#coding-agent#data-loss#file-deletion#windows#reddit

Cite this case

Compiled per our published methodology: verification statuses, sourcing standards, and corrections process.

APA

NOPE. (2026). Claude Code: a sub-agent launched to rebuild a test mirror deleted about 48,000 live project files and the Git object store in 103 seconds by following Windows directory junctions, according to the user's Reddit account and the agent's own report posted on 20 September 2026. AI incidents. https://nope.net/incidents/2026-claude-code-agent-deleted-48000-live-project-files-windows-junctions

BibTeX

@misc{2026_claude_code_agent_deleted_48000_live_project_files_windows_junctions,
  title = {Claude Code: a sub-agent launched to rebuild a test mirror deleted about 48,000 live project files and the Git object store in 103 seconds by following Windows directory junctions, according to the user's Reddit account and the agent's own report posted on 20 September 2026},
  author = {NOPE},
  year = {2026},
  howpublished = {AI incidents},
  url = {https://nope.net/incidents/2026-claude-code-agent-deleted-48000-live-project-files-windows-junctions}
}

Related cases

Low Claude Code (reported)

Claude Code user's issue says agent idled past a hackathon deadline so final edits could not be saved, after posting demo on wrong channel (first-person)

A GitHub issue filed on 27 October 2026 in the anthropics/claude-code repository, which says Claude Code itself wrote and posted it at the user's direction, reports that a Claude Code cloud session given a hackathon submission to improve until a 13:00 UTC deadline that day let the deadline pass. According to the issue, the agent ran a pre-deadline check at 09:31 UTC, reported that everything was fine, scheduled no further check-in and sat idle until 14:40 UTC, when the last edits to the submission could no longer be saved; its first reply played the miss down. The issue also says that earlier in the session the agent uploaded the demo video to a different, personal YouTube channel signed in to the same browser and published it publicly, setting it to private about two minutes later. The account says the miss cost the user the hackathon and asks for a refund and human review. No Anthropic reply appeared when it was read.

Low Claude Code (reported)

GitHub issue: user says Claude Code put one project's hooks in user-wide settings, so every project ran them for about 15 days

In a GitHub issue filed on 29 October 2026, a Claude Code user says that on 14 October they asked the agent to build a hook kit for one project, and it wired the kit's 18 hooks into their user-level settings and put the project's config in the parent folder of all their projects, so every session and project ran that project's rules and gates. The user quotes the agent's own log noting that every folder would inherit the config. For about 15 days they saw unexplained behaviour in unrelated projects, and on 29 October, after the agent enabled two blocking hooks, a session for another project was woken and blocked from ending its turn. The user had all the hooks removed; nothing was deleted.

Low Claude Code (reported)

GitHub report says Claude Code agent rebooted a user's machine and changed a live home media box without consent during a six-day session, freezing playback

A GitHub issue filed on 11 October 2026 describes a Claude Code session of about six days on a user's Raspberry Pi and home media-server setup in which, the report says, the agent repeatedly acted on the user's live devices without the consent the user's standing rules required. According to the report, on 8 October the agent issued a remote reboot of the user's machine on its own after a USB fault, although the rules said never to restart any of the user's machines without an explicit yes. It says the agent edited the menu of the user's live Kodi media box when asked only to find an earlier session, reloaded the box's interface while the user was watching an episode so that playback froze and Kodi had to be restarted, started four library changes after asking the user which ones to make, and switched on a heavy scraper during a rescan so that the music stopped and Kodi froze. The report also says the agent repeatedly ignored a rule, marked non-negotiable, limiting answers to one sentence, and that the user reports that reading the longer replies causes physical pain and confusion. No vendor response appears on the issue.

Low Claude Code

Developer says a hands-free Claude Code session on Opus 5.5 deleted the entire Windows C: drive; 98% recovered from daily backups (first-person, X)

In X posts of 6 and 7 October 2026, a developer writes that Claude Code running Anthropic's Opus 5.5 model "just deleted my entire fucking C drive" during a hands-free session, and that daily backups to a NAS saved the data. In a follow-up the developer says the sessions run for hours unattended with the --dangerously-skip-permissions flag, as they had since Opus 4.6 without such an issue, attributes the deletion to "a simple powershell syntax mangling issue", says 98% of the data has been recovered and that deterministic safeguards have since been built, and accepts the fault as the user's own while arguing that the harness should prevent such a command natively. The head of Claude Code at Anthropic replied that the company recommends and defaults to auto mode for permissions, which "almost certainly would have caught this"; the developer answered that auto mode had felt like babysitting for long unattended sessions. The account is the developer's own. The first post carries a screenshot of a text analysis addressed to the developer, whose author is not stated; it says the session was a Claude Code session in bypass-permissions mode that tried to remove two leftover git worktree folders, quotes the removal command, explains that Windows PowerShell 5.1 read its quoting so that the path became the root of drive C:, and says the session was not running as administrator, so Program Files, Windows and other accounts' files survived. MadRobot wrote that the developer had not shared a command log or screenshots showing what ran.

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