Artifacts deleted server-side with no user action, no retention setting, and no notice (personal plan)

## Summary

Two private Claude Code artifacts were deleted server-side with **no user action, no visible retention setting, no notice, and no recovery path**. One of them held months of live launch-planning state (it used self-save / persistent checkboxes), which is permanently lost.

## Affected artifacts

| Artifact | Title | Last updated | Status |
|---|---|---|---|
| `22be6779-98cb-41b7-af4e-75e81122f3a0` | Neon Ante — Launch Command Center | 2026-07-05 01:57 UTC | **404 "artifact not found"** |
| `c41e61d9-eca8-4f7f-a2f1-18d5909809a0` | Roguelike Mode — Audit Checklist | 2026-07-05 18:35 UTC | **404 "artifact not found"** |

## Evidence / timeline

- **2026-07-25 17:36 UTC** — an Artifact `list` tool result (preserved in a local session transcript) shows both artifacts existing with the last-updated timestamps above.
- **2026-07-16 16:57 UTC** — browser history shows the first artifact fully rendered (the `*.frame.claudeusercontent.com` frame URL with version stamp `_f/1783216627-f0e1` was recorded).
- **2026-08-28 ~16:02 UTC** — both artifacts return "artifact not found — it may have been deleted, or it has not been shared with you" via both the Artifact tool and the browser ("Page not found – Claude").
- Every other artifact on the account, all last updated **2026-07-25 or later**, still resolves. The clean split by last-update date suggests time-based expiry.

## Why this looks like a server-side bug (or an undocumented policy)

- The Claude Code Artifact tool has **no delete action**; no local session touched these artifacts after Jul 25 (verified across all transcripts on the machine).
- The user did not delete them from the gallery.
- The documented artifact retention setting (docs: "Settings > Data & privacy controls") is an **admin page for Team/Enterprise orgs**. This is a **personal plan** — the user has confirmed no such retention setting exists in their settings UI.
- If personal-plan artifacts have a default server-side retention window, it is not surfaced anywhere the user can see, gives no warning before deletion, and silently destroys self-save state.

## Ask

1. Can these two artifacts be restored server-side? (They kept versioned self-saves.)
2. What deleted them — bug, or undocumented retention default?
3. If retention exists for personal plans: surface it in settings, document it on the artifacts docs page, and warn before deletion.

## Environment

- Claude Code CLI on Windows 11 (win32), personal claude.ai plan
- Both artifacts were published from CLI sessions in early July 2026

No repository file or test is named. Start by reproducing the 404 responses for the two artifact IDs through the Artifact tool and browser, then review the documented retention setting and the personal-plan settings described in the report. Done means establishing the deletion cause and handling restoration or the requested retention documentation, setting, and warning changes.

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