diff --git a/skills/versiond-admin/SKILL.md b/skills/versiond-admin/SKILL.md
new file mode 100644
index 0000000..2fec19f
--- /dev/null
+++ b/skills/versiond-admin/SKILL.md
@@ -0,0 +1,80 @@
+# versiond admin skill
+
+Operate the local `versiond` file-versioning service. API base is
+`http://127.0.0.1:9922`, every `/api/v1/*` call needs
+`Authorization: Bearer $(versiond token)`. State: `ok` is healthy,
+`degraded` means act. Remote storage is **unencrypted** (disk-encrypted
+server is the trust model); there are no keys to manage.
+
+## Health first (read these before touching anything)
+
+- `GET /health` → `status`, `degraded_roots`, `pending_paths`, `remote`,
+  `remote_usage {percent,used,total,source}`, `remote_pressure`.
+- `GET /api/v1/progress` → scans, upload queue, monitor counters.
+- `GET /api/v1/stats` → files, versions, storage, top files.
+- `GET /api/v1/metrics` → Prometheus text.
+- `journalctl --user -u versiond -p err` → service errors.
+
+## Deploy / service
+
+- Install/reinstall: `pipx reinstall versiond` (from the repo), then
+  `systemctl --user restart versiond`. Verify: new routes appear in
+  `/openapi.json` (`/admin/*`, `/metrics`).
+- Never bind non-loopback: the server refuses to start otherwise.
+- `versiond status`, `versiond roots`, `versiond add <dir> [--force]`,
+  `versiond progress`, `versiond stats`, `versiond dashboard`.
+
+## Capture policy (what gets versioned)
+
+- Kept: source, configs, dotfiles (allowlist), images, audio/video,
+  archives, databases incl. SQLite journals (folded into verified snapshots),
+  PDFs, fonts. Cap: `limits.max_file_bytes` (default 10 MiB).
+- Never: dependency/build/cache dirs (`node_modules`, `venv`, `target`, …),
+  hidden dirs, `*.pyc/*.o/*.so`, `*.min.js/*.map`, temps (`*.tmp`, `~$*`,
+  `#*#`, `*~`, `4913`), SQLite journals as standalone files.
+- SQLite rule: backup-API snapshot + `integrity_check`; locked/corrupt →
+  loud skip (`database-locked`, `database-corrupt`), never a stored version.
+- Databases >~100MB or hot 7GB-class files: do NOT raise caps blindly —
+  each version is a full copy until chunked blobs exist. Prefer dumps.
+
+## Retention, GC, scheduler (MUST understand before running)
+
+- `retention.keep_days` (default **5**): everything younger kept; older
+  thinned to 1/file/day; per-file latest + pins always kept.
+- `POST /admin/retention/run` (dry_run default true) then
+  `POST /admin/gc` (dry_run default true, `remote: true` also wipes WebDAV).
+- Built-in loop: retention daily, GC weekly (`[scheduler]`). No cron needed.
+- Capacity backstop `scheduler.remote_max_used_percent` (default 70):
+  over-limit runs a pass but NEVER breaks the keep-days floor; health shows
+  `remote_pressure: true` + `remote-over-capacity-limit` → human analyzes
+  (lower keep_days, bigger box). Never auto-delete below the floor.
+
+## Disaster recovery (total local loss), in order
+
+1. Reinstall, `POST /config/remote/adopt {url, username, password,
+   directory}` — takes over the old remote directory.
+2. `POST /admin/reindex` (202 + poll `GET /admin/reindex/{id}`) — rebuilds
+   the index from manifests; everything returns `durable`.
+3. Restore (single/bulk/point-in-time). Blobs stream from WebDAV on demand.
+   SQLite restores are integrity-checked; failures refuse with `unrestorable`.
+
+## Destructive actions (double-check, dry-run first)
+
+- `POST /admin/purge-remote {"today": "dd-mm-yyyy"}` — wipes this
+  installation's remote `blobs/`+`manifests/` async (202 + counts, poll
+  status). Only the claimed directory is ever touched. No local files harmed.
+- `POST /forget {"path", "dry_run"}` — deletes local history under a path.
+- Restores: always dry-run (`POST /restores` → plan), then
+  `POST /restores/{id}/execute`. Pre-restore snapshots make every restore
+  undoable. Targets must resolve inside `$HOME`/roots; symlinks refused.
+
+## Troubleshooting
+
+- `pending_paths` stuck high → coalescer backpressure or rate limits; check
+  `capture:coalesced` vs `capture:committed` counters.
+- `remote: offline` → WebDAV down; spool grows, catches up alone. Check
+  `last_error`, credentials file, server quota.
+- `remote_pressure: true` → over 70%: analyze, don't auto-purge.
+- Root `missing` → path vanished; service polls for return.
+- `watch-limit` on add → smaller root, raise `fs.inotify.max_user_watches`,
+  or `--force` (degraded polling for the overflow).