feat(scanner): report and re-admit model roots that are unavailable (#1108)

`Config._dedupe_existing_paths()` drops roots whose directory does not exist
when the root list is built, so a drive that is switched off while LM starts was
not "an offline root" — it was not a root at all. The Refresh ▾ menu had no row
for it in either state, a full refresh reported nothing (its cached entries
survived only because they fall outside every configured prefix), and plugging
the drive back in changed nothing until the next restart.

* `Config` now records the configured (existence-unfiltered) paths per model
  type — from ComfyUI's list in plugin mode, from the active library snapshot in
  standalone mode, where the host mock filters non-existent paths itself — and
  exposes them through `configured_roots_for()`.
* `ModelScanner.describe_model_roots()` appends configured-but-unavailable roots
  with a live `reachable`, an `available` flag and their cached entry count, so
  `/roots` (and therefore the menu) offers a row in both states: greyed while the
  directory is missing, normal and clickable once it is back.
* `_reconcile_cache()` reports them as `skipped_roots` / `unavailable_paths` with
  reason `root_unavailable` and counts their cached entries in `kept_unreachable`,
  which is what makes the "N models kept" toast appear in the startup-offline
  case. Report-only: they stay outside the scan scope, so nothing about pruning
  changes. A root-scoped scan stays quiet about roots it was not asked about, and
  a folder-scoped scan only mentions a missing root that holds cached entries of
  that folder.
* `Config.admit_configured_roots()` re-runs the per-type prepare helpers against
  the configured paths and APPENDS what is readable now (plus the
  checkpoint/unet/other side maps), then refreshes the preview allowlist, so a
  drive plugged in mid-session can be scanned without restarting. Append-only and
  order-preserving by design: removing a root mid-session would let a later
  settings save persist the loss, and re-sorting would move `*_roots[0]`, which
  derives the recipes directory and the usage-stats file location. `_roots[0]`
  never moves.
* `/roots` and `/scan` admit first, so `describe_model_roots()` stays a pure read
  and a caller that never opens the menu (the browser extension) still gets a
  drive that came back.

Verified on the sandbox with drive-Z switched off before startup: `/roots`
reports `drive-Z reachable=false available=false models=60`, a full refresh
returns `skipped_roots=[drive-Z root_unavailable]`,
`unavailable_paths=[{... kept: 60}]`, `kept_unreachable=60`, and all 432 models
stay cached. Renaming the drive back while the server runs admits it
(`available=true`) and `GET /scan?roots=<drive-Z>` walks it with no restart.
3714 passed, 7 skipped; frontend 1495 passed (149 files); vue widgets 96 passed.

docs/plans/issue-1108-scoped-scan.md

@@ -2,9 +2,9 @@
 
 **Issue:** [#1108](https://github.com/willmiao/ComfyUI-Lora-Manager/issues/1108) — scan a single
 folder/root instead of the whole library.
-**Status:** **P1 and P2 implemented** (2026-10-07). P1 shipped in `470d85cc` (translations in
-`bd184559`); P2 (folder scope + the sidebar entry) is in the working tree. Supersedes the earlier
-draft's per-root *status panel* and persisted *unreachable-subtree* state (both dropped, see
+**Status:** **P1, P2 and Wave 6 implemented** (2026-10-07). P1 shipped in `470d85cc` (translations
+in `bd184559`), P2 in `12930ce7` (translations in `0941f992`). Supersedes the earlier draft's
+per-root *status panel* and persisted *unreachable-subtree* state (both dropped, see
 "Must NOT have").
 
 Implementation notes / deviations from the draft below:
@@ -271,6 +271,85 @@ and in the exact pruning predicate; both get explicit tests.
       `scope_label=pack000`, keeps drive-Z's 6 entries under that folder (`kept_unreachable=6`) and
       leaves all 420 models cached.
 
+## Wave 6 — configured vs currently available roots (approved follow-up)
+
+The P1/P2 work exposed an asymmetry: `Config._dedupe_existing_paths()` drops roots whose directory
+does not exist **at the moment the root list is built** (startup, or applying a library snapshot),
+so a drive that is switched off while LM starts is not "an offline root" — it is not a root at all.
+Consequences, all verified on the sandbox:
+
+* `/roots` does not list it, so the Refresh ▾ menu shows no row for it in either state;
+* a full refresh reports nothing (`kept_unreachable: 0`, no toast) even though its cached entries
+  are kept — they survive only because they fall outside every configured root prefix;
+* plugging the drive back in does not bring the row back: the in-memory list is not re-validated;
+* **plugin mode only:** `Config.save_folder_paths_to_settings()` (called from `Config.__init__`)
+  persists `target_folder_paths["loras"] = list(self.loras_roots)` through
+  `upsert_library(folder_paths=...)`, which **replaces** the library's paths. Starting ComfyUI with
+  a drive switched off therefore *erases that path from `settings.json`* — a configuration loss,
+  not just a display gap. Extra paths are unaffected (that call reuses the stored
+  `extra_folder_paths`), and the same pattern applies to checkpoints/unet/embeddings/other-model
+  primary paths.
+
+### Must have
+
+1. **Never erase an unavailable root from the library config.** `Config` records the *configured*
+   (existence-unfiltered) primary paths per model type while building the live lists, and
+   `save_folder_paths_to_settings()` persists those instead of the filtered ones.
+   `_resolve_valid_default_root()` receives the configured paths in `allowed_paths` too, so a
+   `default_*_root` that sits on a switched-off drive is not "repaired" away.
+2. **Report configured-but-unavailable roots.** `Config.configured_roots_for(model_type)` feeds
+   `ModelScanner.describe_model_roots()`, which appends them with `available: false`, a live
+   `reachable` and their cached entry count — so the Refresh ▾ menu has a row in **both** states
+   (greyed while the directory is missing, normal and clickable once it is back). The reconcile
+   summary reports them as `skipped_roots` / `unavailable_paths` with reason `root_unavailable` and
+   counts their cached entries in `kept_unreachable`, which is what makes the "N models kept" toast
+   appear in the startup-offline case.
+3. **Admit them again, append-only.** `Config.admit_configured_roots()` re-runs the per-type
+   prepare helpers against the configured paths and **appends** what exists now
+   (plus the checkpoint/unet/other side maps) to the live lists, then refreshes the preview
+   allowlist. Called from `/roots` and `/scan`, so a drive plugged in mid-session can be scanned
+   without restarting. Appending (never re-sorting) keeps `loras_roots[0]` — which derives the
+   recipes directory and the usage-stats file location — stable for the whole session.
+
+### Must NOT have
+
+* NO removal of a root from the live lists mid-session (that is what would let a later settings
+  save persist a reduced configuration, and it would move `*_roots[0]`).
+* NO change to the scan/prune scope: a root that is still unavailable stays out of scope, so its
+  entries remain "kept because out of scope" exactly as today.
+* NO persisted unavailable-state, no DB schema change, no per-entry filesystem probe.
+
+### Where "configured" comes from
+
+`Config` records the existence-unfiltered paths while building the live lists, but the *source*
+differs per mode and that matters:
+
+* **Plugin mode:** `folder_paths.get_folder_paths()` is ComfyUI's own list, unfiltered — a path the
+  user removed there must be forgotten, one that is merely missing must be kept. The host list wins.
+* **Standalone mode:** `standalone.MockFolderPaths.get_folder_paths()` already filters
+  `os.path.exists` out of `settings.json`, so the host list cannot answer "what did the user
+  configure". The active **library snapshot** (`libraries[<active>].folder_paths`, falling back to
+  the top-level `folder_paths`) is the record, and it wins there.
+  (`_remember_library_configured_paths()` implements the split.)
+
+### Verification
+
+* Config: a configured path that does not exist is still written back by
+  `save_folder_paths_to_settings()`; a path the host no longer configures is still dropped.
+* Promotion: create the directory after the lists were built → `admit_configured_roots()` adds it
+  **at the end**, keeps every existing root in place, and adds nothing twice.
+* Scanner: `describe_model_roots()` reports the missing root (`available: false`, cached count);
+  a full refresh lists it in `skipped_roots`/`unavailable_paths` and keeps its entries; `/scan`
+  with that root works once the directory is back.
+* Sandbox, drive-Z gone **before** startup: `/roots` reports `drive-Z` with
+  `reachable=false available=false models=60`; a full refresh returns
+  `skipped_roots=[drive-Z root_unavailable]`, `unavailable_paths=[{... kept: 60}]`,
+  `kept_unreachable=60` and leaves all 432 models cached. *(Both measured; before this wave the
+  menu had no row and the refresh reported nothing.)*
+* Sandbox, drive renamed back **while the server runs**: `/roots` admits it
+  (`available=true reachable=true`) and `GET /scan?roots=<drive-Z>` walks it
+  (`scanned_roots=['drive-Z']`, 0 added / 0 removed) — no restart required. *(Measured.)*
+
 ## Known limitations (accepted)
 
 - **Nested symlinks** (a symlink *below* a root pointing at another drive) are only covered when

py/config.py

@@ -1679,6 +1679,105 @@ class Config:
         """
         return list((getattr(self, "_configured_root_paths", None) or {}).get(model_type, []))
 
+    def admit_configured_roots(self) -> List[str]:
+        """Append configured roots that became readable again, never removing any.
+
+        The live lists are built once at startup (and when a library snapshot is
+        applied), so a drive plugged in later is invisible until the process is
+        restarted. Re-running the per-type prepare helpers against the configured
+        paths and appending only the new entries is what makes "plug the drive
+        in, scan it" work without a restart. Nothing is ever dropped or
+        re-ordered — see ``_append_new_paths`` for why order matters.
+
+        Returns the paths that were admitted by this call.
+        """
+        admitted: List[str] = []
+
+        def _extend(current, candidates) -> List[str]:
+            merged = _append_new_paths(list(current or []), candidates)
+            admitted.extend(
+                path for path in merged if path not in (current or [])
+            )
+            return merged
+
+        try:
+            lora_configured = self.configured_roots_for("lora")
+            if lora_configured:
+                self.loras_roots = _extend(
+                    self.loras_roots, self._prepare_lora_paths(lora_configured)
+                )
+
+            checkpoint_configured = self.configured_roots_for("checkpoint")
+            unet_configured = self.configured_roots_for("unet")
+            if checkpoint_configured or unet_configured:
+                (
+                    all_roots,
+                    checkpoint_roots,
+                    unet_roots,
+                ) = self._prepare_checkpoint_paths(
+                    checkpoint_configured, unet_configured
+                )
+                self.base_models_roots = _extend(self.base_models_roots, all_roots)
+                self.checkpoints_roots = _extend(self.checkpoints_roots, checkpoint_roots)
+                self.unet_roots = _extend(self.unet_roots, unet_roots)
+
+            embedding_configured = self.configured_roots_for("embedding")
+            if embedding_configured:
+                self.embeddings_roots = _extend(
+                    self.embeddings_roots,
+                    self._prepare_embedding_paths(embedding_configured),
+                )
+
+            other_configured = self.configured_roots_for("other")
+            if other_configured:
+                (
+                    other_roots,
+                    other_subtypes,
+                    other_per_key,
+                ) = self._prepare_other_paths(
+                    {
+                        key: [
+                            path
+                            for path in self._configured_other_paths_for_key(key)
+                        ]
+                        for key in self._get_enabled_other_folder_keys()
+                    }
+                )
+                self.other_roots = _extend(self.other_roots, other_roots)
+                for root, sub_type in other_subtypes.items():
+                    self.other_root_subtypes.setdefault(root, sub_type)
+                for key, roots in other_per_key.items():
+                    self.other_folder_roots[key] = _append_new_paths(
+                        self.other_folder_roots.get(key, []), roots
+                    )
+        except Exception as exc:  # pragma: no cover - defensive logging
+            logger.warning("Failed to admit configured roots: %s", exc)
+            return admitted
+
+        if admitted:
+            logger.info(
+                "Admitted %d previously unavailable model root(s): %s",
+                len(admitted),
+                ", ".join(admitted),
+            )
+            try:
+                # Previews of the newly admitted drive must be servable again.
+                self.refresh_preview_roots()
+            except Exception as exc:  # pragma: no cover - defensive logging
+                logger.debug("Failed to refresh preview roots: %s", exc)
+        return admitted
+
+    def _configured_other_paths_for_key(self, key: str) -> List[str]:
+        """Configured other-model paths for one folder_paths key (may not exist)."""
+        try:
+            return [
+                path.strip()
+                for path in folder_paths.get_folder_paths(key) or []
+                if isinstance(path, str) and path.strip()
+            ]
+        except Exception:
+            return []
+
     def refresh_other_roots(self) -> None:
         """Rebuild other-model roots after the management toggles changed.
 

py/routes/handlers/model_handlers.py

@@ -1163,6 +1163,11 @@ class ModelQueryHandler:
                 except ValueError as exc:
                     return web.json_response({"error": str(exc)}, status=400)
 
+            # A drive that was plugged in after startup must be scannable without
+            # a restart, and callers that never open the Refresh menu (the browser
+            # extension) have no other chance to admit it.
+            self._service.refresh_model_roots()
+
             if requested_roots:
                 configured = self._service.get_model_roots()
                 unknown = [root for root in requested_roots if root not in configured]
@@ -1206,6 +1211,9 @@ class ModelQueryHandler:
 
     async def get_model_roots(self, request: web.Request) -> web.Response:
         try:
+            # A drive plugged in after startup is admitted here, so the menu shows
+            # it as a normal row instead of "unavailable" until the next restart.
+            self._service.refresh_model_roots()
             roots = self._service.get_model_roots()
             try:
                 root_details = self._service.describe_model_roots()

py/services/base_model_service.py

@@ -954,9 +954,17 @@ class BaseModelService(ABC):
         return self.scanner.last_reconcile_summary
 
     def describe_model_roots(self) -> List[Dict[str, Any]]:
-        """Describe configured roots (label / reachability / cached count)."""
+        """Describe configured roots (label / reachability / cached count).
+
+        Pure read: callers that want a drive which was plugged in after startup to
+        appear as a normal row call :meth:`refresh_model_roots` first.
+        """
         return self.scanner.describe_model_roots()
 
+    def refresh_model_roots(self) -> List[str]:
+        """Admit configured roots that became readable again (append-only)."""
+        return self.scanner.refresh_model_roots()
+
     async def get_model_info_by_name(self, name: str):
         """Get model information by name"""
         return await self.scanner.get_model_info_by_name(name)

py/services/model_scanner.py

@@ -257,7 +257,13 @@ class _UnreachablePaths:
         self._prefixes: List[str] = []
         self._details: Dict[str, Dict[str, Any]] = {}
 
-    def add(self, path: str, reason: str) -> None:
+    def add(self, path: str, reason: str, kept: int = 0) -> None:
+        """Register an unreadable prefix.
+
+        ``kept`` seeds the count for a root whose entries never reach the prune
+        phase because they are outside the scan scope entirely (a configured root
+        that was not even part of the live root list).
+        """
         prefix = _normalized_root_prefix(path)
         with self._lock:
             if prefix in self._details:
@@ -265,7 +271,7 @@ class _UnreachablePaths:
             self._details[prefix] = {
                 'path': path.replace(os.sep, '/'),
                 'reason': reason,
-                'kept': 0,
+                'kept': kept,
             }
             self._prefixes.append(prefix)
 
@@ -1576,6 +1582,44 @@ class ModelScanner:
         """
         return self._last_reconcile_summary
 
+    def get_configured_model_roots(self) -> List[str]:
+        """Roots the user configured for this type, including unavailable ones.
+
+        ``get_model_roots()` answers "what can be walked right now"; this answers
+        "what did the user configure", which is what the refresh menu reports and
+        what must survive a switched-off drive.
+        """
+        try:
+            from ..config import config
+        except Exception:  # pragma: no cover - import guard
+            return []
+
+        # The checkpoint page scans two configured keys.
+        keys = ('checkpoint', 'unet') if self.model_type == 'checkpoint' else (self.model_type,)
+        roots: List[str] = []
+        seen: Set[str] = set()
+        for key in keys:
+            for root in config.configured_roots_for(key):
+                if root and root not in seen:
+                    seen.add(root)
+                    roots.append(root)
+        return roots
+
+    def refresh_model_roots(self) -> List[str]:
+        """Admit configured roots whose directory is readable again.
+
+        Append-only and idempotent: a drive plugged in while the process runs
+        becomes scannable without a restart. Called before describing the roots
+        (`/roots`) and before a scan, so both see the same list.
+        """
+        try:
+            from ..config import config
+
+            return config.admit_configured_roots()
+        except Exception as exc:  # pragma: no cover - defensive logging
+            logger.debug("Failed to refresh model roots: %s", exc)
+            return []
+
     def describe_model_roots(self) -> List[Dict[str, Any]]:
         """Describe the configured roots for the refresh scope menu.
 
@@ -1591,21 +1635,30 @@ class ModelScanner:
             seen.add(root)
             roots.append(root)
 
-        labels = _root_display_labels(roots)
+        # Configured roots that are missing from the live list: their directory
+        # did not exist when it was built (a drive switched off at startup).
+        # They are reported so the menu offers a row in both states instead of
+        # hiding the root until the process is restarted.
+        unavailable = [
+            root for root in self.get_configured_model_roots() if root not in seen
+        ]
+
+        labels = _root_display_labels(roots + unavailable)
         cached_paths = (
             {item.get('file_path', '') for item in self._cache.raw_data}
             if self._cache is not None
             else set()
         )
-        counts = _count_cached_entries_per_root(cached_paths, roots)
+        counts = _count_cached_entries_per_root(cached_paths, roots + unavailable)
         return [
             {
                 'path': root.replace(os.sep, '/'),
                 'label': labels[root],
                 'reachable': os.path.exists(root),
+                'available': root in seen,
                 'models': counts.get(root, 0),
             }
-            for root in roots
+            for root in roots + unavailable
         ]
 
     async def _initialize_cache(self) -> None:
@@ -1732,7 +1785,17 @@ class ModelScanner:
                 seen_roots.add(root_path)
                 configured_roots.append(root_path)
 
-            all_labels = _root_display_labels(configured_roots)
+            # Configured roots that never made it into the live list (their
+            # directory was missing when it was built). They are outside the scan
+            # scope entirely — which is exactly why their cached entries survive
+            # — so they only need reporting, and their labels must not collide
+            # with the live ones.
+            configured_only = [
+                root for root in self.get_configured_model_roots()
+                if root and root not in seen_roots
+            ]
+
+            all_labels = _root_display_labels(configured_roots + configured_only)
             scope_roots = [
                 root for root in configured_roots
                 if scope is None or scope.roots is None or root in scope.roots
@@ -1755,6 +1818,29 @@ class ModelScanner:
                     continue
                 roots.append(root_path)
 
+            # Report the roots that were filtered out of the live list, so a
+            # switched-off drive no longer keeps its models in silence. A scoped
+            # scan stays quiet about them: with explicit roots the caller asked
+            # for specific ones, and for a folder only the roots that actually
+            # hold cached entries of that folder are relevant.
+            if configured_only and (scope is None or scope.roots is None):
+                folder_candidates = [
+                    (root, _scope_prefix(root, scope_folder)) for root in configured_only
+                ]
+                folder_counts = _count_cached_entries_for_prefixes(
+                    cached_paths, folder_candidates
+                )
+                for root_path, _prefix in folder_candidates:
+                    kept = folder_counts.get(root_path, 0)
+                    if scope_folder is not None and not kept:
+                        continue
+                    unreachable.add(root_path, 'root_unavailable', kept=kept)
+                    skipped_roots.append({
+                        'path': root_path.replace(os.sep, '/'),
+                        'label': all_labels.get(root_path, root_path),
+                        'reason': 'root_unavailable',
+                    })
+
             self._collect_offline_symlink_prefixes(roots, unreachable)
 
             # Scope prefixes come from every root the caller asked for (even the

tests/config/test_admit_configured_roots.py

@@ -0,0 +1,132 @@
+"""Wave 6: configured roots that are unavailable must be reportable and
+re-admitted append-only, never dropped from the live lists."""
+
+import os
+
+import pytest
+
+from py import config as config_module
+
+
+def _make_config(**overrides) -> config_module.Config:
+    config = config_module.Config.__new__(config_module.Config)
+    config._path_mappings = {}
+    config._preview_root_paths = set()
+    config._cached_fingerprint = None
+    config.loras_roots = []
+    config.extra_loras_roots = []
+    config.base_models_roots = []
+    config.checkpoints_roots = []
+    config.unet_roots = []
+    config.embeddings_roots = []
+    config.extra_checkpoints_roots = []
+    config.extra_unet_roots = []
+    config.extra_embeddings_roots = []
+    config.other_roots = []
+    config.recipes_path = ""
+    config.other_root_subtypes = {}
+    config.other_folder_roots = {}
+    config._configured_root_paths = {}
+    for key, value in overrides.items():
+        setattr(config, key, value)
+    return config
+
+
+def _normalize(path) -> str:
+    return os.path.normpath(str(path)).replace(os.sep, "/")
+
+
+class TestAppendNewPaths:
+    def test_appends_without_reordering_or_duplicating(self):
+        merged = config_module._append_new_paths(
+            ["/b/loras", "/a/loras"], ["/a/loras", "/c/loras", "", None]
+        )
+        # Existing order is preserved (it derives *_roots[0] consumers) and the
+        # new root lands at the end.
+        assert merged == ["/b/loras", "/a/loras", "/c/loras"]
+
+    def test_matches_case_insensitively(self):
+        merged = config_module._append_new_paths(["C:/Loras"], ["c:/loras"])
+        assert merged == ["C:/Loras"]
+
+
+class TestAdmitConfiguredRoots:
+    def test_admits_a_root_that_became_readable(self, tmp_path):
+        primary = tmp_path / "primary"
+        primary.mkdir()
+        drive = tmp_path / "drive-Z" / "loras"
+
+        config = _make_config(
+            loras_roots=[str(primary)],
+            _configured_root_paths={"lora": [str(primary), str(drive)]},
+        )
+        assert config.configured_roots_for("lora") == [str(primary), str(drive)]
+
+        # Still switched off: nothing to admit.
+        assert config.admit_configured_roots() == []
+        assert config.loras_roots == [str(primary)]
+
+        drive.mkdir(parents=True)
+        admitted = config.admit_configured_roots()
+
+        assert admitted == [str(drive)]
+        assert config.loras_roots == [str(primary), str(drive)]
+        # Idempotent: a second call adds nothing.
+        assert config.admit_configured_roots() == []
+
+    def test_never_removes_a_root_that_disappeared(self, tmp_path):
+        primary = tmp_path / "primary"
+        primary.mkdir()
+        drive = tmp_path / "drive-Z" / "loras"
+        drive.mkdir(parents=True)
+
+        config = _make_config(
+            loras_roots=[str(primary), str(drive)],
+            _configured_root_paths={"lora": [str(drive), str(primary)]},
+        )
+
+        # The drive is switched off after the lists were built: the live list
+        # keeps it (reporting and pruning decide separately) and admission must
+        # not "clean it up" — a later settings save would persist the loss.
+        drive.rmdir()
+        config.admit_configured_roots()
+
+        assert config.loras_roots == [str(primary), str(drive)]
+
+    def test_admits_every_model_type_and_its_side_maps(self, tmp_path):
+        checkpoint_dir = tmp_path / "checkpoints"
+        unet_dir = tmp_path / "unet"
+        embedding_dir = tmp_path / "embeddings"
+        other_dir = tmp_path / "vae"
+        for directory in (checkpoint_dir, unet_dir, embedding_dir, other_dir):
+            directory.mkdir()
+
+        config = _make_config(
+            _configured_root_paths={
+                "checkpoint": [str(checkpoint_dir)],
+                "unet": [str(unet_dir)],
+                "embedding": [str(embedding_dir)],
+                "other": [str(other_dir)],
+            },
+        )
+        config._get_enabled_other_folder_keys = lambda: ["vae"]
+        config._configured_other_paths_for_key = lambda key: [str(other_dir)]
+
+        admitted = config.admit_configured_roots()
+
+        assert set(admitted) == {
+            _normalize(checkpoint_dir),
+            _normalize(unet_dir),
+            _normalize(embedding_dir),
+            _normalize(other_dir),
+        }
+        assert config.base_models_roots == [
+            _normalize(checkpoint_dir),
+            _normalize(unet_dir),
+        ]
+        assert config.checkpoints_roots == [_normalize(checkpoint_dir)]
+        assert config.unet_roots == [_normalize(unet_dir)]
+        assert config.embeddings_roots == [_normalize(embedding_dir)]
+        assert config.other_roots == [_normalize(other_dir)]
+        assert config.other_root_subtypes[_normalize(other_dir)] == "vae"
+        assert config.other_folder_roots["vae"] == [_normalize(other_dir)]

tests/routes/test_model_query_handler.py

@@ -213,21 +213,43 @@ class ScopedScanService:
 
     model_type = "lora"
 
-    def __init__(self, roots=None, summary=None, cancelled=False):
+    def __init__(self, roots=None, summary=None, cancelled=False, unavailable=None):
         self._roots = list(roots or [])
+        self._unavailable = list(unavailable or [])
         self._summary = summary
         self.cancelled = cancelled
         self.scanner = SimpleNamespace(is_cancelled=lambda: self.cancelled)
         self.received_scope = "not-called"
         self.received_rebuild = None
+        self.root_refreshes = 0
 
     def get_model_roots(self):
         return list(self._roots)
 
+    def refresh_model_roots(self):
+        """Mimic the scanner admitting roots that became readable again."""
+        self.root_refreshes += 1
+        return []
+
     def describe_model_roots(self):
         return [
-            {"path": root, "label": root.rsplit("/", 1)[-1], "reachable": True, "models": 7}
+            {
+                "path": root,
+                "label": root.rsplit("/", 1)[-1],
+                "reachable": True,
+                "available": True,
+                "models": 7,
+            }
             for root in self._roots
+        ] + [
+            {
+                "path": root,
+                "label": root.rsplit("/", 1)[-1],
+                "reachable": False,
+                "available": False,
+                "models": 3,
+            }
+            for root in self._unavailable
         ]
 
     async def scan_models(self, force_refresh=False, rebuild_cache=False, scope=None):
@@ -265,6 +287,8 @@ async def test_scan_models_accepts_roots_param():
     assert service.received_scope is not None
     assert service.received_scope.roots == ("/mnt/a",)
     assert service.received_rebuild is False
+    # A drive plugged in after startup is admitted before the roots are validated.
+    assert service.root_refreshes == 1
 
 
 @pytest.mark.asyncio
@@ -307,6 +331,28 @@ async def test_scan_models_rejects_roots_with_full_rebuild():
     assert service.received_scope == "not-called"
 
 
+@pytest.mark.asyncio
+async def test_get_model_roots_reports_configured_but_unavailable_roots():
+    """Wave 6: a root whose directory was missing at startup is still reported."""
+    service = ScopedScanService(
+        roots=["/mnt/a"], unavailable=["/mnt/drive-Z/loras"]
+    )
+    handler = ModelQueryHandler(service=service, logger=logging.getLogger(__name__))
+
+    response = await handler.get_model_roots(SimpleNamespace(query=QueryParams({})))
+    payload = json.loads(response.text)
+
+    assert response.status == 200
+    assert payload["roots"] == ["/mnt/a"]
+    details = {entry["path"]: entry for entry in payload["root_details"]}
+    assert details["/mnt/a"]["available"] is True
+    assert details["/mnt/drive-Z/loras"]["available"] is False
+    assert details["/mnt/drive-Z/loras"]["reachable"] is False
+    assert details["/mnt/drive-Z/loras"]["models"] == 3
+    # Describing the roots admits anything that became readable again.
+    assert service.root_refreshes == 1
+
+
 @pytest.mark.asyncio
 async def test_scan_models_accepts_folder_param():
     service = ScopedScanService(roots=["/mnt/a", "/mnt/b"], summary=SUMMARY)

tests/services/test_model_scanner.py

@@ -2649,6 +2649,112 @@ async def test_reconcile_folder_scope_covers_every_root_holding_it(tmp_path: Pat
     assert _normalize_path(primary / "only-primary" / "c.txt") in paths
 
 
+async def _startup_filtered_scanner(tmp_path: Path, monkeypatch, configured_missing: Path):
+    """Scanner whose live root list lacks a root that the config still holds.
+
+    Models the startup case: the directory did not exist when the live list was
+    built (drive switched off), so `Config` filtered it out while its cached
+    entries are still there.
+    """
+    primary = tmp_path / "primary"
+    (primary / "pack").mkdir(parents=True)
+    (primary / "pack" / "a.txt").write_text("a", encoding="utf-8")
+    configured_missing.mkdir(parents=True)
+    (configured_missing / "pack").mkdir()
+    (configured_missing / "pack" / "b.txt").write_text("b", encoding="utf-8")
+
+    scanner = MultiRootDummyScanner([primary, configured_missing])
+    await scanner._initialize_cache()
+    # The drive goes away before the process starts, as far as the live list is
+    # concerned: keep the roots the filter would have kept.
+    shutil.rmtree(configured_missing)
+    scanner._roots = [str(primary)]
+    monkeypatch.setattr(
+        scanner,
+        "get_configured_model_roots",
+        lambda: [str(primary), str(configured_missing)],
+    )
+    return scanner, primary, configured_missing
+
+
+@pytest.mark.asyncio
+async def test_describe_model_roots_reports_unavailable_configured_root(
+    tmp_path: Path, monkeypatch
+):
+    configured_missing = tmp_path / "drive-Z" / "loras"
+    scanner, primary, missing = await _startup_filtered_scanner(
+        tmp_path, monkeypatch, configured_missing
+    )
+
+    described = scanner.describe_model_roots()
+
+    assert [entry["path"] for entry in described] == [
+        _normalize_path(primary),
+        _normalize_path(missing),
+    ]
+    available, unavailable = described
+    assert available["reachable"] is True
+    assert available["available"] is True
+    # The missing root is reported with its cached count so the refresh menu can
+    # offer it as an offline row instead of hiding it until a restart.
+    assert unavailable["reachable"] is False
+    assert unavailable["available"] is False
+    assert unavailable["models"] == 1
+
+
+@pytest.mark.asyncio
+async def test_reconcile_reports_root_filtered_out_at_startup(tmp_path: Path, monkeypatch):
+    configured_missing = tmp_path / "drive-Z" / "loras"
+    scanner, _primary, missing = await _startup_filtered_scanner(
+        tmp_path, monkeypatch, configured_missing
+    )
+    kept_path = _normalize_path(missing / "pack" / "b.txt")
+
+    summary = await scanner._reconcile_cache()
+
+    assert summary is not None
+    # Nothing is added or removed...
+    assert summary["added"] == 0
+    assert summary["removed"] == 0
+    # ...but the switched-off root is no longer silent: it is reported with the
+    # entries that were kept for it.
+    assert summary["skipped_roots"] == [
+        {
+            "path": _normalize_path(missing),
+            "label": missing.name,
+            "reason": "root_unavailable",
+        }
+    ]
+    assert summary["kept_unreachable"] == 1
+    assert summary["unavailable_paths"] == [
+        {"path": _normalize_path(missing), "reason": "root_unavailable", "kept": 1}
+    ]
+    assert kept_path in {item["file_path"] for item in scanner._cache.raw_data}
+
+
+@pytest.mark.asyncio
+async def test_scoped_scan_stays_quiet_about_filtered_out_roots(tmp_path: Path, monkeypatch):
+    configured_missing = tmp_path / "drive-Z" / "loras"
+    scanner, primary, missing = await _startup_filtered_scanner(
+        tmp_path, monkeypatch, configured_missing
+    )
+
+    summary = await scanner._reconcile_cache(
+        scope=ReconcileScope(roots=(str(primary),))
+    )
+
+    assert summary is not None
+    # The caller asked for one root: a root it did not ask about is not its
+    # business, but its entries are still kept.
+    assert summary["scanned_roots"] == [primary.name]
+    assert "root_unavailable" not in {
+        entry["reason"] for entry in summary["skipped_roots"]
+    }
+    assert _normalize_path(missing / "pack" / "b.txt") in {
+        item["file_path"] for item in scanner._cache.raw_data
+    }
+
+
 @pytest.mark.asyncio
 async def test_reconcile_keeps_entries_under_unreadable_dir(tmp_path: Path, monkeypatch):
     """A directory os.walk cannot enter (permissions, I/O error, offline