From da099820c707ed5714aa8f8f8d86038f00af0ede Mon Sep 17 00:00:00 2001
From: AngusBell97 <124716116+AngusBell97@users.noreply.github.com>
Date: Thu, 10 Sep 2026 21:12:25 +0100
Subject: [PATCH] Improve model selection and downloads in Galaxy

---
 starpilot/assets/model_manager.py             |   4 +-
 starpilot/assets/model_sizes.py               |  81 ++++++++++++
 .../tests/test_download_failure_recovery.py   |  53 ++++++++
 starpilot/assets/tests/test_model_sizes.py    |  99 +++++++++++++++
 .../assets/components/tools/model_hardware.js |  52 ++++++++
 .../assets/components/tools/model_manager.js  | 115 +++++++++++++-----
 .../the_galaxy/assets/mobile/css/material.css |   4 +
 .../mobile/js/components/FeatureHelp.js       |  95 +++++++++++++++
 .../assets/mobile/js/views/ModelManager.js    | 112 ++++++++++++-----
 .../tests/test_model_catalog_sizes_api.py     |  23 ++++
 .../the_galaxy/tests/test_model_hardware.mjs  |  17 +++
 .../tests/test_model_manager_legacy_state.mjs |  17 +++
 .../test_model_manager_lifecycle_browser.mjs  | 104 ++++++++++++++++
 .../test_model_manager_selection_browser.mjs  |  65 ++++++++++
 .../tests/test_model_manager_state.mjs        |  44 +++++++
 .../tests/test_model_profile_payloads.py      |  23 ++++
 .../tests/test_model_selection_contract.py    |  16 +++
 starpilot/system/the_galaxy/the_galaxy.py     |  11 +-
 18 files changed, 871 insertions(+), 64 deletions(-)
 create mode 100644 starpilot/assets/model_sizes.py
 create mode 100644 starpilot/assets/tests/test_download_failure_recovery.py
 create mode 100644 starpilot/assets/tests/test_model_sizes.py
 create mode 100644 starpilot/system/the_galaxy/assets/components/tools/model_hardware.js
 create mode 100644 starpilot/system/the_galaxy/assets/mobile/js/components/FeatureHelp.js
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_catalog_sizes_api.py
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_hardware.mjs
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_manager_legacy_state.mjs
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_manager_lifecycle_browser.mjs
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_manager_selection_browser.mjs
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_manager_state.mjs
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_profile_payloads.py
 create mode 100644 starpilot/system/the_galaxy/tests/test_model_selection_contract.py

diff --git a/starpilot/assets/model_manager.py b/starpilot/assets/model_manager.py
index f174af12c0..32d1ae5307 100644
--- a/starpilot/assets/model_manager.py
+++ b/starpilot/assets/model_manager.py
@@ -937,6 +937,7 @@ class ModelManager:
     try:
       self._download_model(model_to_download, allow_gpu_without_gpu)
     finally:
+      self.downloading_model = False
       self.params_memory.remove(ALLOW_GPU_DOWNLOAD_WITHOUT_GPU_PARAM)
 
   def _download_artifact_to_path(self, model_key: str, file_path: Path, remote_filename: str,
@@ -1057,8 +1058,8 @@ class ModelManager:
       self.params_memory.put(DOWNLOAD_PROGRESS_PARAM, "eGPU variant downloaded!")
       return True
     finally:
-      self.params_memory.remove(MODEL_LAB_DOWNLOAD_PARAM)
       self.downloading_model = False
+      self.params_memory.remove(MODEL_LAB_DOWNLOAD_PARAM)
 
   def _download_model(self, model_to_download: str, allow_gpu_without_gpu: bool):
     self.downloading_model = True
@@ -1129,6 +1130,7 @@ class ModelManager:
     try:
       self._download_all_models(allow_gpu_without_gpu)
     finally:
+      self.downloading_model = False
       self.params_memory.remove(ALLOW_GPU_DOWNLOAD_WITHOUT_GPU_PARAM)
 
   def _download_all_models(self, allow_gpu_without_gpu: bool):
diff --git a/starpilot/assets/model_sizes.py b/starpilot/assets/model_sizes.py
new file mode 100644
index 0000000000..d7595fc73d
--- /dev/null
+++ b/starpilot/assets/model_sizes.py
@@ -0,0 +1,81 @@
+"""Local logical payload sizes. No HEAD requests, hashing, or model mutation."""
+from pathlib import Path
+import re
+import threading
+import time
+
+MAX_DECLARED_BYTES = 1 << 50
+
+
+def positive_size(value):
+  return value if type(value) is int and 0 < value <= MAX_DECLARED_BYTES else None
+
+
+def artifact_size(path, declared=None):
+  path = Path(path)
+  declared = positive_size(declared)
+  result = {'fileSizeBytes': None, 'declaredSizeBytes': declared, 'downloadedBytes': None,
+            'sizeSource': 'metadata' if declared else 'unknown',
+            'sizeStatus': 'declared' if declared else 'unknown'}
+  try:
+    if path.is_file():
+      size = path.stat().st_size
+      result.update(fileSizeBytes=size if size > 0 else None, downloadedBytes=size,
+                    sizeSource='installed', sizeStatus='complete' if size > 0 else 'partial')
+    else:
+      manifest = Path(str(path) + '.chunkmanifest')
+      chunks = [p for p in path.parent.glob(path.name + '.chunk*')
+                if re.fullmatch(re.escape(path.name) + r'\.chunk\d+of\d+', p.name) and p.is_file()]
+      if not manifest.is_file() and not chunks:
+        return result
+      count = None
+      if manifest.is_file():
+        try:
+          text = manifest.read_text().strip()
+          count = int(text) if text.isdecimal() and len(text) <= 5 else None
+        except (ValueError, UnicodeError):
+          pass
+      expected = [Path(f'{path}.chunk{i + 1:02d}of{count:02d}') for i in range(count)] if count and count <= 10000 else []
+      complete = bool(expected) and set(chunks) == set(expected)
+      downloaded = sum(p.stat().st_size for p in chunks)
+      result.update(downloadedBytes=downloaded, fileSizeBytes=downloaded if complete and downloaded > 0 else None,
+                    sizeSource='installed' if complete else 'partial',
+                    sizeStatus='complete' if complete and downloaded > 0 else 'partial')
+    if result['fileSizeBytes'] is not None and declared and declared != result['fileSizeBytes']:
+      result['sizeStatus'] = 'mismatch'
+  except OSError:
+    result.update(fileSizeBytes=None, downloadedBytes=None, sizeSource='unknown', sizeStatus='unknown')
+  return result
+
+
+class ModelSizes:
+  """Bounded cache for local catalogue size reads, independent of statistics."""
+  def __init__(self):
+    self.lock = threading.Lock()
+    self.sizes = {}
+
+  def size(self, path, declared):
+    # Short TTL avoids repeated directory scans on status polls, not stale sizes
+    # across completed downloads. Bad metadata is treated as unknown by helper.
+    key = (str(path), repr(declared))
+    with self.lock:
+      cached = self.sizes.get(key)
+      if cached is None or time.monotonic() >= cached[0]:
+        cached = (time.monotonic() + 2, artifact_size(path, declared))
+        if len(self.sizes) > 1000:
+          self.sizes.clear()
+        self.sizes[key] = cached
+      return dict(cached[1])
+
+  def annotate(self, models, models_path, builtin_path, metadata, accelerator_filename):
+    for model in models:
+      key = model['value']
+      entry = metadata.get(key, {})
+      entry = entry if isinstance(entry, dict) else {}
+      path = builtin_path if model['builtin'] else Path(models_path) / f'{key}_driving_tinygrad.pkl'
+      model.update(self.size(path, entry.get('artifact_size')))
+      variants = entry.get('accelerator_artifacts', {})
+      variant = variants.get('chestnut') if isinstance(variants, dict) else None
+      if isinstance(variant, dict):
+        model['modelLabFileSize'] = self.size(Path(models_path) / accelerator_filename(key), variant.get('artifact_size'))
+    return models
diff --git a/starpilot/assets/tests/test_download_failure_recovery.py b/starpilot/assets/tests/test_download_failure_recovery.py
new file mode 100644
index 0000000000..ee12b69586
--- /dev/null
+++ b/starpilot/assets/tests/test_download_failure_recovery.py
@@ -0,0 +1,53 @@
+"""Source-class fault seam; native imports and real Params are not exercised."""
+import ast
+from pathlib import Path
+import pytest
+
+
+def manager_class():
+  tree = ast.parse((Path(__file__).parents[1] / 'model_manager.py').read_text())
+  names = {'MODEL_LAB_ACCELERATOR', 'ALLOW_GPU_DOWNLOAD_WITHOUT_GPU_PARAM',
+           'DOWNLOAD_PROGRESS_PARAM', 'MODEL_DOWNLOAD_PARAM', 'MODEL_LAB_DOWNLOAD_PARAM',
+           'DEFAULT_MODEL_KEY', 'MODEL_KEY_CANONICAL_MAP'}
+  nodes = [n for n in tree.body if
+           isinstance(n, ast.Assign) and any(isinstance(t, ast.Name) and t.id in names for t in n.targets) or
+           isinstance(n, ast.FunctionDef) and n.name in {'canonical_model_key', 'is_builtin_model_key'} or
+           isinstance(n, ast.ClassDef) and n.name == 'ModelManager']
+  ns = {'Path': Path, 'model_accelerator_artifact_metadata': lambda *args: {}}
+  exec(compile(ast.Module(body=nodes, type_ignores=[]), 'model_manager.py', 'exec'), ns)
+  return ns['ModelManager']
+
+
+class FaultParams:
+  def __init__(self, cleanup_fault=False):
+    self.cleanup_fault = cleanup_fault
+  def get_bool(self, key):
+    return False
+  def put(self, *args):
+    raise OSError('synthetic Params write failure')
+  def remove(self, *args):
+    if self.cleanup_fault:
+      raise OSError('synthetic Params removal failure')
+
+
+@pytest.mark.parametrize('cleanup_fault', [False, True])
+@pytest.mark.parametrize('operation', ['single', 'all', 'accelerator'])
+def test_failed_download_releases_refresh_gate(cleanup_fault, operation):
+  cls = manager_class()
+  manager = cls.__new__(cls)
+  manager.downloading_model = False
+  manager.params_memory = FaultParams(cleanup_fault)
+  if operation == 'all':
+    manager._download_all_models = lambda allow: manager._download_model('rdf43', allow)
+    call = manager.download_all_models
+  elif operation == 'accelerator':
+    # Failure at upstream artifact metadata lookup; cleanup must release the gate.
+    def fail():
+      raise OSError('synthetic hardware lookup failure')
+    cls.download_model_accelerator.__globals__['model_accelerator_artifact_metadata'] = lambda *args: fail()
+    call = lambda: manager.download_model_accelerator('gpu')
+  else:
+    call = lambda: manager.download_model('rdf43')
+  with pytest.raises(OSError):
+    call()
+  assert manager.downloading_model is False
diff --git a/starpilot/assets/tests/test_model_sizes.py b/starpilot/assets/tests/test_model_sizes.py
new file mode 100644
index 0000000000..e3bbc8ec79
--- /dev/null
+++ b/starpilot/assets/tests/test_model_sizes.py
@@ -0,0 +1,99 @@
+from pathlib import Path
+
+import pytest
+
+from openpilot.starpilot.assets.model_sizes import artifact_size, positive_size
+
+
+@pytest.mark.parametrize('value', [None, True, False, 0, -1, '123', 'abc', 1.2, 2**60])
+def test_invalid_declared_size(value):
+  assert positive_size(value) is None
+
+
+def test_monolithic_actual_size_precedes_chunks_and_reports_mismatch(tmp_path):
+  path = tmp_path / 'model.pkl'
+  path.write_bytes(b'actual model')
+  Path(str(path) + '.chunkmanifest').write_text('1')
+  Path(str(path) + '.chunk01of01').write_bytes(b'old chunk')
+  result = artifact_size(path, 2)
+  assert result['fileSizeBytes'] == len(b'actual model')
+  assert result['downloadedBytes'] == len(b'actual model')
+  assert result['sizeStatus'] == 'mismatch'
+
+
+def test_complete_chunks_exclude_manifest_and_missing_chunk_is_partial(tmp_path):
+  path = tmp_path / 'model.pkl'
+  Path(str(path) + '.chunkmanifest').write_text('2')
+  first, second = Path(str(path) + '.chunk01of02'), Path(str(path) + '.chunk02of02')
+  first.write_bytes(b'abc')
+  second.write_bytes(b'defg')
+  assert artifact_size(path, 7)['fileSizeBytes'] == 7
+  assert artifact_size(path, 7)['sizeStatus'] == 'complete'
+  second.unlink()
+  result = artifact_size(path, 7)
+  assert result['sizeStatus'] == 'partial'
+  assert result['fileSizeBytes'] is None
+  assert result['downloadedBytes'] == 3 and result['declaredSizeBytes'] == 7
+
+
+@pytest.mark.parametrize('manifest', ['0', '-1', 'bad', '100000000000000', '', '2.0'])
+def test_malformed_chunk_manifest_is_not_complete(tmp_path, manifest):
+  path = tmp_path / 'model.pkl'
+  Path(str(path) + '.chunkmanifest').write_text(manifest)
+  assert artifact_size(path)['fileSizeBytes'] is None
+  assert artifact_size(path)['sizeStatus'] == 'partial'
+
+
+def test_missing_manifest_and_missing_file(tmp_path):
+  path = tmp_path / 'model.pkl'
+  assert artifact_size(path, 20)['sizeStatus'] == 'declared'
+  assert artifact_size(path)['sizeStatus'] == 'unknown'
+  Path(str(path) + '.chunk01of02').write_bytes(b'partial')
+  assert artifact_size(path)['sizeStatus'] == 'partial'
+  assert artifact_size(path)['downloadedBytes'] == 7
+
+
+def test_stat_failure_is_unknown(tmp_path, monkeypatch):
+  path = tmp_path / 'model.pkl'
+  path.write_bytes(b'x')
+  def failed(*args, **kwargs):
+    raise PermissionError('test denied')
+  monkeypatch.setattr(Path, 'stat', failed)
+  assert artifact_size(path, 10)['sizeStatus'] == 'unknown'
+
+
+def test_zero_byte_artifact_is_not_valid_size(tmp_path):
+  path = tmp_path / 'model.pkl'
+  path.touch()
+  assert artifact_size(path)['fileSizeBytes'] is None
+  assert artifact_size(path)['sizeStatus'] == 'partial'
+
+
+def test_catalog_annotation_is_independent_of_statistics(tmp_path):
+  from openpilot.starpilot.assets.model_sizes import ModelSizes
+  (tmp_path / 'builtin.pkl').write_bytes(b'123')
+  (tmp_path / 'gpu_driving_tinygrad.pkl').write_bytes(b'12345')
+  (tmp_path / 'gpu_accel.pkl').write_bytes(b'1234567')
+  models = [{'value': 'stock', 'builtin': True}, {'value': 'gpu', 'builtin': False}]
+  result = ModelSizes().annotate(models, tmp_path, tmp_path / 'builtin.pkl',
+    {'gpu': {'artifact_size': 5, 'accelerator_artifacts': {'chestnut': {'artifact_size': 7}}}}, lambda key: key + '_accel.pkl')
+  assert result[0]['fileSizeBytes'] == 3
+  assert result[1]['fileSizeBytes'] == 5
+  assert result[1]['modelLabFileSize']['fileSizeBytes'] == 7
+  assert all('stats' not in model for model in result)
+
+
+def test_size_cache_refresh_and_bound(tmp_path, monkeypatch):
+  from openpilot.starpilot.assets import model_sizes
+  now = [0]
+  monkeypatch.setattr(model_sizes.time, 'monotonic', lambda: now[0])
+  service = model_sizes.ModelSizes()
+  path = tmp_path / 'model.pkl'
+  assert service.size(path, None)['fileSizeBytes'] is None
+  path.write_bytes(b'123')
+  assert service.size(path, None)['fileSizeBytes'] is None
+  now[0] = 3
+  assert service.size(path, None)['fileSizeBytes'] == 3
+  for index in range(1002):
+    service.size(tmp_path / str(index), None)
+  assert len(service.sizes) <= 1001
diff --git a/starpilot/system/the_galaxy/assets/components/tools/model_hardware.js b/starpilot/system/the_galaxy/assets/components/tools/model_hardware.js
new file mode 100644
index 0000000000..e10131aa01
--- /dev/null
+++ b/starpilot/system/the_galaxy/assets/components/tools/model_hardware.js
@@ -0,0 +1,52 @@
+// Presentation only. No Params writes, telemetry collection or inferred mileage.
+const FILTER_KEY = "galaxy.modelManager.hardwareFilter";
+const FILTERS = new Set(["both", "gpu", "comma"]);
+
+export function readHardwareFilter() {
+  try {
+    const value = localStorage.getItem(FILTER_KEY);
+    return FILTERS.has(value) ? value : "both";
+  } catch {
+    return "both";
+  }
+}
+
+export function saveHardwareFilter(value) {
+  const filter = FILTERS.has(value) ? value : "both";
+  try { localStorage.setItem(FILTER_KEY, filter); } catch { /* View still works without storage. */ }
+  return filter;
+}
+
+export function matchesHardware(model, filter) {
+  if (filter === "gpu") return model?.requiresGpu === true;
+  if (filter === "comma") return model?.requiresGpu === false;
+  return true;
+}
+
+export function hardwareLabel(model) {
+  if (model?.requiresGpu === true) return "GPU · External";
+  if (model?.requiresGpu === false) return "Comma · On-device";
+  return "Hardware unknown";
+}
+
+function bytes(value) {
+  return Number.isSafeInteger(value) && value > 0 ? value : null;
+}
+
+function formatBytes(value) {
+  return value >= 1e9 ? `${(value / 1e9).toFixed(2)} GB` : `${(value / 1e6).toFixed(1)} MB`;
+}
+
+export function fileSizeText(model) {
+  // modelSize is an architecture class, never a byte count.
+  const installed = bytes(model?.fileSizeBytes);
+  const declared = bytes(model?.declaredSizeBytes);
+  const downloaded = bytes(model?.downloadedBytes);
+  if (model?.partial || model?.sizeStatus === "partial") {
+    return `Partial: ${downloaded ? formatBytes(downloaded) : "unknown"} / ${declared ? formatBytes(declared) : "unknown"}`;
+  }
+  if (installed && declared && installed !== declared) return `${formatBytes(installed)} · size mismatch`;
+  if (installed) return formatBytes(installed);
+  if (declared) return `${formatBytes(declared)} · declared`;
+  return "Unavailable";
+}
diff --git a/starpilot/system/the_galaxy/assets/components/tools/model_manager.js b/starpilot/system/the_galaxy/assets/components/tools/model_manager.js
index 690110771a..683b60c671 100644
--- a/starpilot/system/the_galaxy/assets/components/tools/model_manager.js
+++ b/starpilot/system/the_galaxy/assets/components/tools/model_manager.js
@@ -5,6 +5,7 @@ const state = reactive({
   refreshing: false,
   error: "",
   actionBusy: false,
+  selectionUncertain: true,
   sortMode: "release_date",
   communityFavoriteFilter: "all",
   userFavoriteFilter: "all",
@@ -27,7 +28,10 @@ const state = reactive({
 
 let initialized = false;
 let pollingHandle = null;
-let statusInFlight = false;
+let statusInFlight = null;
+let statusGeneration = 0;
+let viewGeneration = 0;
+let selectionWrite = null;
 let lastStatusSignature = "";
 
 const REQUEST_TIMEOUT_MS = 20000;
@@ -216,11 +220,16 @@ async function fetchJson(url, options = {}) {
 }
 
 async function fetchStatus() {
-  if (statusInFlight) return;
-  statusInFlight = true;
+  const generation = statusGeneration;
+  if (statusInFlight === generation) return;
+  statusInFlight = generation;
 
   try {
+    // Remount readback must follow settlement of an already sent selection.
+    if (selectionWrite) await selectionWrite.catch(() => {});
+    if (generation !== statusGeneration || !isModelRouteActive()) return;
     const payload = await fetchJson("/api/models/status");
+    if (generation !== statusGeneration || !isModelRouteActive()) return;
 
     const models = Array.isArray(payload.models)
       ? payload.models.filter(model => model && typeof model === "object")
@@ -249,6 +258,15 @@ async function fetchStatus() {
     };
 
     state.error = "";
+    state.selectionUncertain = false;
+    // selected attributes cannot reset a select's dirty native value after a user edit.
+    queueMicrotask(() => {
+      if (generation !== statusGeneration || !isModelRouteActive()) return;
+      for (const profile of ["small", "big"]) {
+        const select = document.getElementById(`mm-active-${profile}-model-select`);
+        if (select) select.value = profile === "big" ? state.activeBigModel : state.activeSmallModel;
+      }
+    });
 
     const signature = [
       state.models.length,
@@ -271,12 +289,15 @@ async function fetchStatus() {
       });
     }
   } catch (error) {
+    if (generation !== statusGeneration || !isModelRouteActive()) return;
     state.error = error?.message || String(error);
     logDebug("Status fetch failed", state.error);
   } finally {
-    statusInFlight = false;
-    state.loading = false;
-    state.refreshing = false;
+    if (statusInFlight === generation) statusInFlight = null;
+    if (generation === statusGeneration && isModelRouteActive()) {
+      state.loading = false;
+      state.refreshing = false;
+    }
   }
 }
 
@@ -296,8 +317,9 @@ async function refreshAll(showToast = false) {
 function ensurePolling() {
   if (pollingHandle) return;
 
+  const generation = viewGeneration;
   const poll = async () => {
-    if (!isModelRouteActive()) {
+    if (generation !== viewGeneration || !isModelRouteActive()) {
       pollingHandle = null;
       return;
     }
@@ -307,7 +329,7 @@ function ensurePolling() {
       await fetchStatus();
       nextDelay = state.status.downloading ? ACTIVE_POLL_INTERVAL_MS : IDLE_POLL_INTERVAL_MS;
     } finally {
-      pollingHandle = setTimeout(poll, nextDelay);
+      if (generation === viewGeneration) pollingHandle = setTimeout(poll, nextDelay);
     }
   };
 
@@ -317,13 +339,13 @@ function ensurePolling() {
 async function setActiveModel(modelKey, profile = "") {
   const model = state.models.find(entry => safeText(entry?.value, "") === safeText(modelKey, ""));
   const resolvedProfile = profile || (model?.requiresGpu ? "big" : "small");
-  const payload = await fetchJson("/api/models/active", {
+  selectionWrite = fetchJson("/api/models/active", {
     method: "PUT",
     headers: { "Content-Type": "application/json" },
     body: JSON.stringify({ profile: resolvedProfile, model: modelKey }),
   });
 
-  notify(payload.message || `Selected "${modelKey}".`);
+  try { return await selectionWrite; } finally { selectionWrite = null; }
 }
 
 async function startDownload(modelKey) {
@@ -391,6 +413,9 @@ async function refreshManifest() {
 }
 
 async function runAction(action, modelKey = "") {
+  const selecting = ["select", "select-small", "select-big"].includes(action);
+  if (!isModelRouteActive() || (selecting && state.selectionUncertain)) return;
+  const generation = viewGeneration;
   if (state.actionBusy) {
     notify("Please wait for the current action to finish.", "error");
     return;
@@ -411,9 +436,14 @@ async function runAction(action, modelKey = "") {
     }
 
     if (action === "select" || action === "select-small" || action === "select-big") {
-      if (!modelKey) return;
+      // Empty Active Big explicitly disables that profile; other selections require a model.
+      if (!modelKey && action !== "select-big") return;
       const profile = action === "select-small" ? "small" : action === "select-big" ? "big" : "";
-      await setActiveModel(modelKey, profile);
+      state.selectionUncertain = true;
+      ++statusGeneration; // Invalidate pre-write polls, including their finalisers.
+      const payload = await setActiveModel(modelKey, profile);
+      if (generation !== viewGeneration || !isModelRouteActive()) return;
+      notify(payload.message || `Selected "${modelKey}".`);
     } else if (action === "download") {
       if (!modelKey) return;
       await startDownload(modelKey);
@@ -434,18 +464,21 @@ async function runAction(action, modelKey = "") {
       await setUserFavorite(modelKey, false);
     }
 
+    if (generation !== viewGeneration || !isModelRouteActive()) return;
     await fetchStatus();
   } catch (error) {
+    if (generation !== viewGeneration || !isModelRouteActive()) return;
     notify(error?.message || String(error), "error");
+    // A failed response does not establish whether the server accepted the write.
+    await fetchStatus();
   } finally {
-    state.actionBusy = false;
+    if (generation === viewGeneration && isModelRouteActive()) state.actionBusy = false;
   }
 }
 
 function bindDomHandlers() {
   if (window.__modelManagerHandlersBound) return;
   window.__modelManagerHandlersBound = true;
-
   document.addEventListener("click", event => {
     if (!isModelRouteActive()) return;
 
@@ -475,6 +508,8 @@ function bindDomHandlers() {
       const modelKey = safeText(target.value, "");
       const profile = target.id === "mm-active-big-model-select" ? "big" : "small";
       if (!modelKey && profile !== "big") return;
+      // Native selects change before their event; display only verified state.
+      target.value = profile === "big" ? state.activeBigModel : state.activeSmallModel;
       runAction(`select-${profile}`, modelKey).catch(() => {});
       return;
     }
@@ -532,7 +567,7 @@ function renderActions(model) {
 
   if (model.installed) {
     return html`
-      <button class="mm-btn mm-btn-secondary" data-mm-action="select-${profile}" data-model="${modelKey}">Set Active ${profile === "big" ? "Big" : "Small"}</button>
+      <button class="mm-btn mm-btn-secondary" disabled="${() => state.actionBusy || state.selectionUncertain}" data-mm-action="select-${profile}" data-model="${modelKey}">Set Active ${profile === "big" ? "Big" : "Small"}</button>
       ${model.builtin
         ? ""
         : html`<button class="mm-btn mm-btn-danger" data-mm-action="delete" data-model="${modelKey}">Delete</button>`}
@@ -599,19 +634,41 @@ function renderSeriesSection(seriesName, models) {
   `;
 }
 
+function ensureModelView() {
+  if (document.querySelector(".mm-wrapper")) return;
+  const generation = ++viewGeneration;
+  ++statusGeneration;
+  clearTimeout(pollingHandle);
+  pollingHandle = null;
+  // Arrow has no unmount hook. Observe this mount's removal, not just pathname:
+  // a quick leave-and-return must not revive an old write/readback continuation.
+  queueMicrotask(() => {
+    if (generation !== viewGeneration) return;
+    const observer = new MutationObserver(() => {
+      if (generation !== viewGeneration) { observer.disconnect(); return; }
+      // Arrow may replace the wrapper during an ordinary reactive render.
+      if (document.querySelector(".mm-wrapper") && isModelRouteActive()) return;
+      observer.disconnect();
+      if (generation !== viewGeneration) return;
+      ++viewGeneration;
+      ++statusGeneration;
+      clearTimeout(pollingHandle);
+      pollingHandle = null;
+    });
+    observer.observe(document.body, { childList: true, subtree: true });
+    state.actionBusy = false;
+    state.selectionUncertain = true;
+    refreshAll();
+    ensurePolling();
+  });
+}
+
 export function ModelManager() {
   if (!initialized) {
     initialized = true;
     bindDomHandlers();
-    logDebug("Initializing component");
-    refreshAll().catch(error => {
-      state.error = error?.message || String(error);
-      state.loading = false;
-      state.refreshing = false;
-      logDebug("Initial refresh failed", state.error);
-    });
   }
-  ensurePolling();
+  ensureModelView();
 
   return html`
     <div class="mm-wrapper">
@@ -643,14 +700,14 @@ export function ModelManager() {
         <span class="mm-chip">Loaded: ${() => getCurrentModelName()}</span>
         <span class="mm-chip mm-chip-device-gpu">Active Small: ${() => getModelName(state.activeSmallModel)}</span>
         <span class="mm-chip mm-chip-egpu">Active Big: ${() => getModelName(state.activeBigModel)}</span>
-        <span class="mm-chip">Progress: ${safeText(state.status.progress, "Idle")}</span>
+        <span class="mm-chip">Progress: ${() => safeText(state.status.progress, "Idle")}</span>
         <span class="mm-chip">${() => getUserFavoriteModels(false).length} personal favorites</span>
         ${() => state.status.isOnroad ? html`<span class="mm-chip mm-chip-warning">Onroad: actions disabled</span>` : ""}
       </div>
 
       <div class="mm-filters">
         <label class="mm-filter-label" for="mm-active-small-model-select">Active Small</label>
-        <select class="mm-select" id="mm-active-small-model-select">
+        <select class="mm-select" id="mm-active-small-model-select" disabled="${() => state.actionBusy || state.selectionUncertain}">
           ${() => {
             const orderedInstalled = getInstalledModels("small").sort((a, b) => {
               const aCurrent = safeText(a.value) === state.activeSmallModel ? 0 : 1;
@@ -669,7 +726,7 @@ export function ModelManager() {
         </select>
 
         <label class="mm-filter-label" for="mm-active-big-model-select">Active Big</label>
-        <select class="mm-select" id="mm-active-big-model-select">
+        <select class="mm-select" id="mm-active-big-model-select" disabled="${() => state.actionBusy || state.selectionUncertain}">
           ${() => {
             const orderedInstalled = getInstalledModels("big").sort((a, b) => {
               const aCurrent = safeText(a.value) === state.activeBigModel ? 0 : 1;
@@ -692,7 +749,7 @@ export function ModelManager() {
         </select>
 
         <label class="mm-filter-label" for="mm-favorite-model-select">Favorite Models</label>
-        <select class="mm-select" id="mm-favorite-model-select" disabled="${() => getUserFavoriteModels(true).length === 0}">
+        <select class="mm-select" id="mm-favorite-model-select" disabled="${() => state.actionBusy || state.selectionUncertain || getUserFavoriteModels(true).length === 0}">
           ${(() => {
             const favorites = getUserFavoriteModels(true);
             return favorites.length > 0
@@ -746,7 +803,7 @@ export function ModelManager() {
 
       ${() => !state.loading ? html`
         <div class="mm-list">
-          ${(() => {
+          ${() => {
             if (state.sortMode === "release_date") {
               const models = getReleaseOrderedModels();
               return models.length === 0
@@ -758,7 +815,7 @@ export function ModelManager() {
             return seriesNames.length === 0
               ? html`<div class="mm-empty">No models available.</div>`
               : seriesNames.map(seriesName => renderSeriesSection(seriesName, grouped[seriesName]));
-          })()}
+          }}
         </div>
       ` : ""}
     </div>
diff --git a/starpilot/system/the_galaxy/assets/mobile/css/material.css b/starpilot/system/the_galaxy/assets/mobile/css/material.css
index 9b987df931..1084480262 100644
--- a/starpilot/system/the_galaxy/assets/mobile/css/material.css
+++ b/starpilot/system/the_galaxy/assets/mobile/css/material.css
@@ -1,3 +1,7 @@
+/* Download status changes must not move the viewport to another card. */
+.gx-model-manager { overflow-anchor: none; }
+.gx-model-manager .gx-row .gx-field { min-width: 0; }
+
 .gx-personalities { overflow-anchor: none; }
 #gx-personality-settings { padding: 0 var(--sp-4) var(--sp-4); }
 .gx-personalities__live { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
diff --git a/starpilot/system/the_galaxy/assets/mobile/js/components/FeatureHelp.js b/starpilot/system/the_galaxy/assets/mobile/js/components/FeatureHelp.js
new file mode 100644
index 0000000000..680e897c66
--- /dev/null
+++ b/starpilot/system/the_galaxy/assets/mobile/js/components/FeatureHelp.js
@@ -0,0 +1,95 @@
+// Shared confirmation dialog for model downloads.
+let activeDialog = null
+let dialogId = 0
+function installStyle() {
+  if (document.getElementById("gx-feature-help-style")) return
+  const style = document.createElement("style")
+  style.id = "gx-feature-help-style"
+  style.textContent = `
+    .gx-help-dialog {box-sizing:border-box;width:min(640px,calc(100% - 24px));max-width:calc(100% - 24px);max-height:var(--gx-help-height,85dvh);margin:auto;padding:0;border:1px solid var(--outline-variant,#667085);border-radius:var(--radius-lg,18px);background:var(--background,#20252e);color:var(--on-surface,#edf0f5);box-shadow:0 16px 64px #0008;overflow:auto;overscroll-behavior:contain;overflow-wrap:anywhere;font-family:inherit}
+    .gx-help-dialog::backdrop {background:#0009}
+    .gx-help-dialog__heading {margin:0;padding:20px 20px 8px;font-size:1.25rem;line-height:1.35}
+    .gx-help-dialog__body {padding:0 20px;line-height:1.6}
+    .gx-help-dialog__body p {white-space:pre-line;margin:12px 0}
+    .gx-help-dialog__body h4 {font-size:1rem;margin:20px 0 8px}
+    .gx-help-dialog__actions {display:flex;justify-content:flex-end;flex-wrap:wrap;gap:12px;padding:16px 20px;position:sticky;bottom:0;background:var(--background,#20252e);border-top:1px solid var(--outline-variant,#667085)}
+    .gx-help-dialog__actions button {min-height:44px}
+  `
+  document.head.appendChild(style)
+}
+
+// Native modal provides inert background, Escape and focus restoration. No settings writes.
+export function openGalaxyHelpDialog({ title, paragraphs = [], troubleshooting = [], confirmLabel = "Close", cancelLabel = "" }) {
+  installStyle()
+  activeDialog?.()
+  return new Promise(resolve => {
+    const opener = document.activeElement
+    const dialog = document.createElement("dialog")
+    dialog.className = "gx-help-dialog"
+    dialog.setAttribute("aria-modal", "true")
+    const titleId = `gx-help-title-${++dialogId}`
+    dialog.setAttribute("aria-labelledby", titleId)
+    const heading = document.createElement("h3")
+    heading.id = titleId
+    heading.className = "gx-help-dialog__heading"
+    heading.textContent = title
+    const body = document.createElement("div")
+    body.className = "gx-help-dialog__body"
+    const paragraph = text => { const p = document.createElement("p"); p.textContent = text; body.appendChild(p) }
+    paragraphs.forEach(paragraph)
+    if (troubleshooting.length) {
+      const h = document.createElement("h4"); h.textContent = "Troubleshooting"; body.appendChild(h)
+      troubleshooting.forEach(paragraph)
+    }
+    const actions = document.createElement("div")
+    actions.className = "gx-help-dialog__actions"
+    let settled = false
+    const finish = result => {
+      if (settled) return
+      settled = true
+      window.removeEventListener("hashchange", cancel)
+      window.removeEventListener("resize", resize)
+      window.visualViewport?.removeEventListener("resize", resize)
+      if (activeDialog === cancel) activeDialog = null
+      dialog.close()
+      dialog.remove()
+      if (opener?.isConnected) opener.focus({ preventScroll: true })
+      resolve(result)
+    }
+    const cancel = () => finish(false)
+    const resize = () => {
+      // CSS zoom changes available CSS-pixel space independently of device scale.
+      let zoom = 1
+      for (let node = document.body; node; node = node.parentElement) zoom *= parseFloat(getComputedStyle(node).zoom) || 1
+      dialog.style.setProperty("--gx-help-height", `${Math.max(100, ((window.visualViewport?.height || innerHeight) - 24) / zoom)}px`)
+    }
+    const button = (label, result, secondary) => {
+      const b = document.createElement("button"); b.type = "button"; b.textContent = label
+      b.className = `gx-btn${secondary ? " gx-btn--tonal" : ""}`
+      b.addEventListener("click", () => finish(result)); actions.appendChild(b)
+    }
+    if (cancelLabel) button(cancelLabel, false, true)
+    button(confirmLabel, true, false)
+    dialog.append(heading, body, actions)
+    dialog.addEventListener("cancel", event => { event.preventDefault(); cancel() })
+    dialog.addEventListener("click", event => {
+      const box = dialog.getBoundingClientRect()
+      if (event.target === dialog && (event.clientX < box.left || event.clientX > box.right || event.clientY < box.top || event.clientY > box.bottom)) cancel()
+    })
+    dialog.addEventListener("keydown", event => {
+      if (event.key !== "Tab") return
+      const buttons = [...actions.querySelectorAll("button")]
+      const first = buttons[0], last = buttons.at(-1)
+      if (event.shiftKey && document.activeElement === first) { event.preventDefault(); last.focus() }
+      if (!event.shiftKey && document.activeElement === last) { event.preventDefault(); first.focus() }
+    })
+    window.addEventListener("hashchange", cancel)
+    window.addEventListener("resize", resize)
+    window.visualViewport?.addEventListener("resize", resize)
+    document.body.appendChild(dialog)
+    activeDialog = cancel
+    resize()
+    dialog.showModal()
+    actions.querySelector("button").focus({ preventScroll: true })
+  })
+}
diff --git a/starpilot/system/the_galaxy/assets/mobile/js/views/ModelManager.js b/starpilot/system/the_galaxy/assets/mobile/js/views/ModelManager.js
index f9570ec3aa..a4fa5af797 100644
--- a/starpilot/system/the_galaxy/assets/mobile/js/views/ModelManager.js
+++ b/starpilot/system/the_galaxy/assets/mobile/js/views/ModelManager.js
@@ -1,6 +1,8 @@
 import { api, showSnackbar } from "../api.js"
 import { usePolling } from "../composables.js"
 import { GalaxyConfirm } from "../components/GalaxyModal.js"
+import { openGalaxyHelpDialog } from "../components/FeatureHelp.js"
+import { readHardwareFilter, saveHardwareFilter, matchesHardware, hardwareLabel, fileSizeText } from "/assets/components/tools/model_hardware.js"
 
 function text(value, fallback = "") {
   return value === null || value === undefined ? fallback : String(value)
@@ -11,6 +13,9 @@ function releasedTs(value) {
   return Number.isNaN(n) ? 0 : n
 }
 
+// Survives SPA unmount: a new instance must read after a sent write settles.
+let selectionWrite = null
+
 export const ModelManager = {
   name: "ModelManager",
   data() {
@@ -18,10 +23,13 @@ export const ModelManager = {
       loading: true,
       error: "",
       busy: "",
+      selectionUncertain: true,
+      statusGeneration: 0,
+      disposed: false,
       sortMode: "release_date",
       userFilter: "all",
       communityFilter: "all",
-      allowGpu: false,
+      hardwareFilter: readHardwareFilter(),
       models: [],
       currentModel: "",
       activeSmallModel: "",
@@ -53,6 +61,7 @@ export const ModelManager = {
       const mode = this.sortMode
       const rows = (this.models || [])
         .filter((m) => m && typeof m === "object")
+        .filter((m) => matchesHardware(m, this.hardwareFilter))
         .filter((m) => this.userFilter === "all" ? true : !!m.userFavorite === (this.userFilter === "yes"))
         .filter((m) => this.communityFilter === "all" ? true : !!m.communityFavorite === (this.communityFilter === "yes"))
       rows.sort((a, b) => {
@@ -64,9 +73,6 @@ export const ModelManager = {
       })
       return rows
     },
-    anyGpuBlocked() {
-      return (this.models || []).some((m) => !!m.requiresGpu && !m.gpuAvailable)
-    },
     downloadTargetLabel() {
       if (this.status.downloadAll) return "all missing models"
       const key = text(this.status.modelToDownload, "")
@@ -78,10 +84,16 @@ export const ModelManager = {
     this.poll = usePolling(() => this.refresh(), { interval: 2000 })
     this.poll.start()
   },
-  beforeUnmount() { this.poll?.destroy() },
+  beforeUnmount() {
+    this.disposed = true
+    ++this.statusGeneration
+    this.poll?.destroy()
+  },
   methods: {
-    gpuBlocked(model) {
-      return !!model.requiresGpu && !model.gpuAvailable && !this.allowGpu
+    hardwareLabel,
+    fileSizeText,
+    setHardwareFilter(value) {
+      this.hardwareFilter = saveHardwareFilter(value)
     },
     rowState(model) {
       const key = text(model.value, "")
@@ -99,8 +111,12 @@ export const ModelManager = {
       return !this.status.isOnroad
     },
     async refresh() {
+      const generation = ++this.statusGeneration
       try {
+        if (selectionWrite) await selectionWrite.catch(() => {})
+        if (this.disposed || generation !== this.statusGeneration) return
         const p = await api.getModelStatus()
+        if (this.disposed || generation !== this.statusGeneration) return
         this.models = Array.isArray(p.models) ? p.models.filter((m) => m && typeof m === "object") : []
         this.currentModel = text(p.currentModel, "")
         this.activeSmallModel = text(p.activeSmallModel, "")
@@ -119,13 +135,17 @@ export const ModelManager = {
           isOnroad: !!p.isOnroad,
         }
         this.error = ""
+        this.selectionUncertain = false
         this.loading = false
       } catch (e) {
+        if (this.disposed || generation !== this.statusGeneration) return
         this.error = e?.message || String(e)
         this.loading = false
       }
     },
     async runAction(action, model = null) {
+      const selecting = action === "select-small" || action === "select-big"
+      if (this.disposed || (selecting && this.selectionUncertain)) return
       if (this.busy) {
         showSnackbar("Please wait for the current action to finish.", "error")
         return
@@ -138,16 +158,41 @@ export const ModelManager = {
       const label = text(model && model.label, key || "model")
       this.busy = `${action}:${key}`
       try {
+        let allowGpu = false
+        const needsGpuPrompt = action === "download"
+          ? model?.requiresGpu && !model.gpuAvailable
+          : action === "downloadAll" && this.models.some(m => !m.installed && m.requiresGpu && !m.gpuAvailable)
+        if (needsGpuPrompt) {
+          allowGpu = await openGalaxyHelpDialog({
+            title: "No external GPU detected",
+            paragraphs: [action === "downloadAll"
+              ? "This download includes models that require an external GPU. You can download them now, but they cannot run until a compatible GPU is connected and detected."
+              : `“${label}” requires an external GPU. You can download it now, but it cannot run until a compatible GPU is connected and detected.`,
+              "GPU model files can be large. Downloading does not activate a model or change the model currently in use."],
+            confirmLabel: "Download anyway", cancelLabel: "Cancel",
+          })
+          if (!allowGpu || this.disposed) return
+          // The car can change state while a confirmation is open.
+          await this.refresh()
+          if (this.disposed || this.error || !this.actionAllowedOnroad(action) || this.status.downloading) {
+            if (!this.disposed) showSnackbar("Download not started. Check the device status and try again while parked.", "error")
+            return
+          }
+        }
         let msg = ""
         if (action === "select-small" || action === "select-big") {
           const profile = action === "select-big" ? "big" : "small"
-          const p = await api.setActiveModel(profile, key)
+          this.selectionUncertain = true
+          ++this.statusGeneration // Pre-write polls cannot reconcile this selection.
+          selectionWrite = api.setActiveModel(profile, key)
+          let p
+          try { p = await selectionWrite } finally { selectionWrite = null }
           msg = p?.message || `Selected "${label}".`
         } else if (action === "download") {
-          const p = await api.startModelDownload(key, this.allowGpu)
+          const p = await api.startModelDownload(key, allowGpu)
           msg = p?.message || `Downloading "${label}"...`
         } else if (action === "downloadAll") {
-          const p = await api.downloadAllModels(this.allowGpu)
+          const p = await api.downloadAllModels(allowGpu)
           msg = p?.message || "Started downloading all models."
         } else if (action === "cancel") {
           const p = await api.postAction("/api/models/cancel")
@@ -175,17 +220,21 @@ export const ModelManager = {
           const p = await api.postAction("/api/models/refresh_manifest")
           msg = p?.message || "Model manifest refreshed."
         }
+        if (this.disposed) return
         if (msg) showSnackbar(msg)
         await this.refresh()
       } catch (e) {
+        if (this.disposed) return
         showSnackbar(e?.message || String(e), "error")
+        // Reconcile a possibly accepted request before releasing the action lock.
+        await this.refresh()
       } finally {
-        this.busy = ""
+        if (!this.disposed) this.busy = ""
       }
     },
   },
   template: `
-    <div class="gx-view">
+    <div class="gx-view gx-model-manager">
       <div v-if="loading" class="gx-card">
         <div class="gx-loading" style="padding: var(--sp-4);">Loading models...</div>
       </div>
@@ -200,7 +249,7 @@ export const ModelManager = {
             <span class="gx-chip">{{ summary.installed }} installed</span>
             <span class="gx-chip">{{ summary.missing }} missing</span>
             <span class="gx-chip">{{ summary.total }} total</span>
-            <span class="gx-chip" style="background:var(--primary);color:var(--on-primary);">Active: {{ currentLabel }}</span>
+            <span class="gx-chip" style="background:var(--primary);color:var(--on-primary);">Selected: {{ currentLabel }}</span>
           </div>
           <div style="padding: 0 var(--sp-3) var(--sp-3);">
             <div v-if="error" class="gx-alert gx-alert--warn" style="border:none; margin:0 0 8px;">
@@ -226,23 +275,23 @@ export const ModelManager = {
             <i class="bi bi-sliders"></i>
             <span class="gx-section__title">Controls</span>
           </div>
-          <div style="padding: var(--sp-3); display:grid; gap:12px;">
+          <div style="padding: var(--sp-3); display:grid; grid-template-columns:minmax(0, 1fr); gap:12px;">
             <div style="display:flex; gap:8px; flex-wrap:wrap;">
               <button v-if="status.downloading" type="button" class="gx-btn gx-btn--danger" :disabled="!!busy" @click="runAction('cancel')"><i class="bi bi-stop-circle"></i> Cancel Download</button>
-              <button v-else type="button" class="gx-btn" :disabled="!!busy" @click="runAction('downloadAll')"><i class="bi bi-download"></i> Download All Missing</button>
+              <button v-else type="button" class="gx-btn" :disabled="!!busy" @click="runAction('downloadAll')"><i class="bi bi-download"></i> Download all missing — entire catalogue</button>
               <button type="button" class="gx-btn gx-btn--tonal" :disabled="!!busy" @click="runAction('refresh')"><i v-if="busy === 'refresh:'" class="bi bi-arrow-repeat gx-spin"></i><i v-else class="bi bi-arrow-clockwise"></i> Refresh</button>
             </div>
 
             <div class="gx-row" style="border-top:none;">
               <span class="gx-row__label">Active Small</span>
-              <select class="gx-field" style="flex:1;" :value="activeSmallModel" :disabled="!!busy || status.isOnroad" @change="runAction('select-small', installedSmallModels.find(m => m.value === $event.target.value))">
+              <select class="gx-field" style="flex:1;" :value="activeSmallModel" :disabled="!!busy || selectionUncertain || status.isOnroad" @change="runAction('select-small', installedSmallModels.find(m => m.value === $event.target.value))">
                 <option v-for="m in installedSmallModels" :key="m.value" :value="m.value">{{ m.label || m.value }}</option>
               </select>
             </div>
 
             <div class="gx-row" style="border-top:none;">
               <span class="gx-row__label">Active Big</span>
-              <select class="gx-field" style="flex:1;" :value="activeBigModel" :disabled="!!busy || status.isOnroad" @change="$event.target.value ? runAction('select-big', installedBigModels.find(m => m.value === $event.target.value)) : runAction('select-big')">
+              <select class="gx-field" style="flex:1;" :value="activeBigModel" :disabled="!!busy || selectionUncertain || status.isOnroad" @change="$event.target.value ? runAction('select-big', installedBigModels.find(m => m.value === $event.target.value)) : runAction('select-big')">
                 <option value="">None — always use Active Small</option>
                 <option v-for="m in installedBigModels" :key="m.value" :value="m.value">{{ m.label || m.value }}</option>
               </select>
@@ -256,6 +305,15 @@ export const ModelManager = {
               </select>
             </div>
 
+            <div class="gx-row" style="border-top:none;">
+              <label class="gx-row__label" for="gx-model-hardware">Model hardware</label>
+              <select id="gx-model-hardware" class="gx-field" style="flex:1; min-width:0;" :value="hardwareFilter" @change="setHardwareFilter($event.target.value)">
+                <option value="both">Both</option>
+                <option value="gpu">GPU models only</option>
+                <option value="comma">Comma models only</option>
+              </select>
+            </div>
+
             <div style="display:flex; gap:8px; flex-wrap:wrap;">
               <select class="gx-field" style="flex:1; min-width:140px;" :value="userFilter" @change="userFilter = $event.target.value">
                 <option value="all">Your Favorite: All</option>
@@ -269,22 +327,11 @@ export const ModelManager = {
               </select>
             </div>
 
-            <div class="gx-row" style="border-top:none;">
-              <div class="gx-row__info">
-                <span class="gx-row__label">Download GPU models without GPU</span>
-                <span v-if="anyGpuBlocked" class="gx-row__desc">GPU models are very large and will not run without an external GPU.</span>
-              </div>
-              <label class="gx-switch">
-                <input type="checkbox" v-model="allowGpu" />
-                <span class="gx-switch__track"></span>
-                <span class="gx-switch__thumb"></span>
-              </label>
-            </div>
           </div>
         </section>
 
         <template v-if="!sorted.length">
-          <div class="gx-card"><div class="gx-empty">No models available.</div></div>
+          <div class="gx-card"><div class="gx-empty">No models match these filters. Try Both or clear the favourite filters.</div></div>
         </template>
         <template v-else>
           <div class="gx-card-grid">
@@ -299,10 +346,11 @@ export const ModelManager = {
                 <div style="margin-top:6px; display:flex; flex-wrap:wrap; gap:6px;">
                   <span class="gx-chip">{{ m.value }}</span>
                   <span v-if="m.builtin" class="gx-chip">Built-in</span>
-                  <span class="gx-chip">{{ m.requiresGpu ? 'eGPU' : 'On-device GPU' }}</span>
+                  <span class="gx-chip">{{ hardwareLabel(m) }}</span>
                   <span v-if="m.version" class="gx-chip">Version {{ m.version }}</span>
                   <span v-if="m.released" class="gx-chip">Released {{ m.released }}</span>
                   <span v-if="m.partial" class="gx-chip">Partial Files</span>
+                  <span class="gx-chip">File size: {{ fileSizeText(m) }}</span>
                 </div>
               </div>
               <button type="button" class="gx-icon-btn" :disabled="!!busy" :title="m.userFavorite ? 'Remove from your favorites' : 'Add to your favorites'" @click="runAction(m.userFavorite ? 'unfavorite' : 'favorite', m)">
@@ -320,11 +368,11 @@ export const ModelManager = {
                 <button type="button" class="gx-btn gx-btn--danger" :disabled="!!busy" @click="runAction('cancel', m)"><i class="bi bi-x-circle"></i> Cancel</button>
               </template>
               <template v-else-if="rowState(m) === 'installed'">
-                <button type="button" class="gx-btn" :disabled="!!busy" @click="runAction(m.requiresGpu ? 'select-big' : 'select-small', m)"><i class="bi bi-play-fill"></i> Set Active {{ m.requiresGpu ? 'Big' : 'Small' }}</button>
+                <button type="button" class="gx-btn" :disabled="!!busy || selectionUncertain" @click="runAction(m.requiresGpu ? 'select-big' : 'select-small', m)"><i class="bi bi-play-fill"></i> Set Active {{ m.requiresGpu ? 'Big' : 'Small' }}</button>
                 <button v-if="!m.builtin" type="button" class="gx-btn gx-btn--tonal" style="color:var(--error);" :disabled="!!busy" @click="runAction('delete', m)"><i class="bi bi-trash"></i> Delete</button>
               </template>
               <template v-else>
-                <button type="button" class="gx-btn" :disabled="!!busy || gpuBlocked(m)" @click="runAction('download', m)"><i class="bi bi-download"></i> {{ gpuBlocked(m) ? 'GPU Required' : 'Download' }}</button>
+                <button type="button" class="gx-btn" :disabled="!!busy || status.isOnroad" @click="runAction('download', m)"><i class="bi bi-download"></i> Download</button>
               </template>
             </div>
             </section>
diff --git a/starpilot/system/the_galaxy/tests/test_model_catalog_sizes_api.py b/starpilot/system/the_galaxy/tests/test_model_catalog_sizes_api.py
new file mode 100644
index 0000000000..7178cd9a1b
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_catalog_sizes_api.py
@@ -0,0 +1,23 @@
+"""Catalogue sizes stay available without importing model statistics."""
+from test_dashboard_stats import _load_server_module, FakeParams
+
+
+def test_catalog_status_has_independent_sizes(monkeypatch, tmp_path):
+  server = _load_server_module()
+  assert server._import_galaxy_web_symbols()
+  app = server.Flask('model_sizes_test')
+  server.setup(app)
+  class CatalogParams(FakeParams):
+    def get_default_value(self, key):
+      return {'Model': 'fixture-default', 'ModelName': 'Fixture default'}.get(key)
+  monkeypatch.setattr(server, 'params', CatalogParams({'IsOnroad': False}))
+  monkeypatch.setattr(server, 'params_memory', FakeParams({}))
+  monkeypatch.setattr(server, 'MODELS_PATH', tmp_path)
+  response = app.test_client().get('/api/models/status')
+  assert response.status_code == 200, response.get_json()
+  result = response.get_json()
+  assert result['models']
+  assert 'statistics' not in result
+  for model in result['models']:
+    assert {'fileSizeBytes', 'declaredSizeBytes', 'downloadedBytes', 'sizeSource', 'sizeStatus'} <= model.keys()
+    assert 'stats' not in model
diff --git a/starpilot/system/the_galaxy/tests/test_model_hardware.mjs b/starpilot/system/the_galaxy/tests/test_model_hardware.mjs
new file mode 100644
index 0000000000..c3e14374b0
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_hardware.mjs
@@ -0,0 +1,17 @@
+import assert from 'node:assert/strict';
+import {readHardwareFilter,saveHardwareFilter,matchesHardware,hardwareLabel,fileSizeText} from '../assets/components/tools/model_hardware.js';
+assert.equal(readHardwareFilter(),'both');
+const stored=new Map();globalThis.localStorage={getItem:k=>stored.get(k),setItem:(k,v)=>stored.set(k,v)};
+for (const value of ['both','gpu','comma']) {assert.equal(saveHardwareFilter(value),value);assert.equal(readHardwareFilter(),value);}
+assert.equal(saveHardwareFilter('invalid'),'both');
+assert.equal(matchesHardware({},'gpu'),false);assert.equal(matchesHardware({},'comma'),false);assert.equal(matchesHardware({},'both'),true);
+assert.equal(matchesHardware({requiresGpu:true},'gpu'),true);assert.equal(matchesHardware({requiresGpu:false},'comma'),true);
+assert.equal(hardwareLabel({}),'Hardware unknown');
+assert.equal(fileSizeText({modelSize:'big'}),'Unavailable');
+assert.equal(fileSizeText({fileSizeBytes:1500000000}),'1.50 GB');
+assert.equal(fileSizeText({declaredSizeBytes:1200000}),'1.2 MB · declared');
+assert.equal(fileSizeText({fileSizeBytes:1500000000,declaredSizeBytes:1000000000}),'1.50 GB · size mismatch');
+assert.equal(fileSizeText({partial:true,downloadedBytes:1200000,declaredSizeBytes:3000000}),'Partial: 1.2 MB / 3.0 MB');
+for(const size of [-1,0,NaN,Infinity,'123',true])assert.equal(fileSizeText({fileSizeBytes:size}),'Unavailable');
+globalThis.localStorage={getItem:()=>{throw Error('blocked')},setItem:()=>{throw Error('blocked')}};assert.equal(readHardwareFilter(),'both');assert.equal(saveHardwareFilter('gpu'),'gpu');
+console.log('PASS: hardware filtering, persistence, unknown/mismatch/partial/declared sizes');
diff --git a/starpilot/system/the_galaxy/tests/test_model_manager_legacy_state.mjs b/starpilot/system/the_galaxy/tests/test_model_manager_legacy_state.mjs
new file mode 100644
index 0000000000..a442ee82d7
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_manager_legacy_state.mjs
@@ -0,0 +1,17 @@
+// Existing classic UI: verify only selection/lifecycle compatibility fixes.
+import assert from 'node:assert/strict';
+import {readFileSync} from 'node:fs';
+const source=readFileSync(new URL('../assets/components/tools/model_manager.js',import.meta.url),'utf8');
+const notices=[];globalThis.window={location:{pathname:'/manage_models'},showSnackbar:(...a)=>notices.push(a)};
+const selects={};globalThis.document={getElementById:id=>selects[id]??=({value:''})};
+const api=new Function('reactive','html',source.replace(/^import .*$/gm,'').replace('export function ModelManager','function ModelManager')+';return {state,fetchStatus,runAction};')(x=>x,()=>{});
+const payload=(active='gpu')=>({models:[{value:'gpu',installed:true,requiresGpu:true}],activeBigModel:active,activeSmallModel:'small',currentModel:'small',summary:{},isOnroad:false});
+const response=(data,ok=true)=>({ok,status:ok?200:503,json:async()=>data});
+let active='gpu',failWrite=false,failRead=false,hold=null,writes=[];
+globalThis.fetch=async(url,opts)=>{if(opts.method==='PUT'){writes.push(JSON.parse(opts.body));if(failWrite)return response({error:'uncertain'},false);active=writes.at(-1).model;return response({message:'selected'});}if(url==='/api/models/cancel'){writes.push('cancel');return response({});}if(hold){const value=hold;hold=null;return value;}return response(failRead?{error:'read failed'}:payload(active),!failRead);};
+await api.fetchStatus();assert.equal(api.state.selectionUncertain,false);assert.equal(selects['mm-active-big-model-select'].value,'gpu');
+let release;hold=new Promise(resolve=>release=resolve);const old=api.fetchStatus();await api.runAction('select-big','');release(response(payload('gpu')));await old;assert.equal(api.state.activeBigModel,'');assert.equal(selects['mm-active-big-model-select'].value,'');assert.deepEqual(writes,[{profile:'big',model:''}]);
+failWrite=true;failRead=true;await api.runAction('select-big','gpu');assert.equal(api.state.selectionUncertain,true);assert.equal(api.state.actionBusy,false);await api.runAction('select-big','gpu');assert.equal(writes.length,2);await api.runAction('cancel');assert.equal(writes.length,3);
+failRead=false;await api.fetchStatus();assert.equal(api.state.selectionUncertain,false);assert.equal(api.state.activeBigModel,'');
+window.location.pathname='/elsewhere';await api.runAction('select-big','gpu');assert.equal(writes.length,3);
+console.log('PASS: legacy explicit None, stale poll, readback failure lock, retry, cancellation and route guard');
diff --git a/starpilot/system/the_galaxy/tests/test_model_manager_lifecycle_browser.mjs b/starpilot/system/the_galaxy/tests/test_model_manager_lifecycle_browser.mjs
new file mode 100644
index 0000000000..9ac81f492c
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_manager_lifecycle_browser.mjs
@@ -0,0 +1,104 @@
+// Real Chromium, shipped components, synthetic API only. No device/network fall-through.
+import assert from 'node:assert/strict';
+import {readFileSync, writeFileSync, mkdirSync} from 'node:fs';
+import {fileURLToPath} from 'node:url';
+const {chromium} = await import(process.env.PLAYWRIGHT_MODULE || 'playwright');
+const root = (process.env.REPO || fileURLToPath(new URL('../../../../', import.meta.url))) + '/starpilot/system/the_galaxy';
+const out = process.env.EVIDENCE;
+if (out) mkdirSync(out, {recursive:true});
+const browser = await chromium.launch({executablePath:process.env.BROWSER_EXECUTABLE, args:['--no-sandbox']});
+const results=[];
+const tick=()=>new Promise(r=>setTimeout(r,100));
+try {
+for (const surface of ['classic','mobile']) for (const scenario of ['stale-poll','reject-read-failure','abort-read-failure','leave-write','leave-readback']) {
+ const context=await browser.newContext({viewport:{width:1200,height:850}});
+ const writes=[], unexpected=[], errors=[]; let active='gpu-a', heldGet=null, heldPut=null, holdNext=false, failReads=false, gets=0;
+ const models=['gpu-a','gpu-b','small'].map(value=>({value,label:value,installed:true,requiresGpu:value!=='small',gpuAvailable:true}));
+ const payload=()=>({models,activeBigModel:active,activeSmallModel:'small',currentModel:'small',summary:{installed:3,total:3},isOnroad:false,downloading:true,modelToDownload:'other'});
+ const mobile=surface==='mobile';
+ const mount=mobile ? `import {createApp} from 'vue';import {ModelManager} from '/assets/mobile/js/views/ModelManager.js';let app;window.mount=()=>{app=createApp(ModelManager);window.vm=app.mount('#app')};window.leave=()=>app.unmount();window.poll=()=>window.vm.refresh();window.act=(a)=>window.vm.runAction(a);` : `import {html} from '/assets/vendor/arrow-core.js';import {ModelManager} from '/assets/components/tools/model_manager.js';window.mount=()=>html\`\${()=>ModelManager()}\`(document.querySelector('#app'));window.leave=()=>document.querySelector('#app').replaceChildren();`;
+ await context.route('**/*',async route=>{
+  const req=route.request(),u=new URL(req.url());
+  if(u.origin!=='http://galaxy.invalid') {unexpected.push(req.url());return route.abort();}
+  if(u.pathname==='/api/models/status' && req.method()==='GET') {
+   gets++; const json=payload();
+   if(holdNext) {holdNext=false;heldGet={route,json};return;}
+   return route.fulfill(failReads?{status:503,json:{error:'Synthetic read failure'}}:{json});
+  }
+  if(req.method()!=='GET') {
+   writes.push({method:req.method(),path:u.pathname,body:req.postData()?req.postDataJSON():null});
+   if(u.pathname==='/api/models/cancel') return route.fulfill({json:{message:'cancelled'}});
+   if(u.pathname!=='/api/models/active') {unexpected.push(req.url());return route.abort();}
+   if(scenario==='leave-write') {heldPut=route;return;}
+   if(scenario!=='reject-read-failure') active=writes.at(-1).body.model;
+   if(scenario.includes('read-failure')) {failReads=true;return scenario.startsWith('abort')?route.abort('connectionreset'):route.fulfill({status:503,json:{error:'Synthetic rejection'}});}
+   if(scenario==='leave-readback') holdNext=true;
+   return route.fulfill({json:{message:'selected'}});
+  }
+  if(u.pathname.startsWith('/assets/')) {
+   try {
+    let body=readFileSync(root+u.pathname);
+    if(u.pathname.endsWith('/tools/model_manager.js')) body=body.toString()+ '\nwindow.poll=()=>fetchStatus();window.act=(a)=>runAction(a);';
+    return route.fulfill({body,contentType:u.pathname.endsWith('.css')?'text/css':'text/javascript'});
+   } catch(e) {unexpected.push(u.pathname);return route.abort();}
+  }
+  if(u.pathname!=='/manage_models') {unexpected.push(u.pathname);return route.abort();}
+  return route.fulfill({contentType:'text/html',body:`<script type="importmap">{"imports":{"vue":"/assets/vendor/vue/vue.esm-browser.js"}}</script><div id="snackbar_wrapper"></div><main id="app"></main><script type="module">${mount}window.mount();</script>`});
+ });
+ const page=await context.newPage();page.on('pageerror',e=>errors.push(e.message));
+ // Capture snackbar effects without changing the shipped API module.
+ await page.addInitScript(()=>{
+  // Hold periodic polling; every race uses explicitly released real requests.
+  const timeout=window.setTimeout;window.setTimeout=(fn,ms,...args)=>timeout(fn,[1000,2000,4000].includes(ms)?60000:ms,...args);
+  window.notices=[];window.showSnackbar=(...a)=>window.notices.push(a);
+  new MutationObserver(records=>{for(const r of records) if(r.target.id==='snackbar_wrapper') for(const n of r.addedNodes) window.notices.push(n.textContent);}).observe(document,{childList:true,subtree:true});
+ });
+ const select=mobile?page.locator('.gx-row').filter({has:page.getByText('Active Big',{exact:true})}).locator('select'):page.locator('#mm-active-big-model-select');
+ const until=async(fn,msg)=>{for(let i=0;i<80;i++){if(await fn())return;await tick();}throw new Error(msg);};
+ let failure=null;
+ try {
+  await page.goto('http://galaxy.invalid/manage_models');
+  await until(async()=>await select.count() && await select.inputValue()==='gpu-a','initial selection');
+  if(scenario==='stale-poll') {holdNext=true;await page.evaluate(()=>{window.poll()});await until(()=>heldGet,'held prewrite poll');}
+  await select.selectOption('');
+  await until(()=>writes.length===1,'selection PUT');
+  assert.deepEqual(writes,[{method:'PUT',path:'/api/models/active',body:{profile:'big',model:''}}]);
+  if(scenario==='stale-poll') {
+   await tick(); await heldGet.route.fulfill({json:heldGet.json});heldGet=null;await tick();
+   assert.equal(await select.inputValue(),'','old poll must not overwrite accepted selection');
+   assert.equal(await select.isDisabled(),false,'post-write readback unlocks');
+  } else if(scenario.includes('read-failure')) {
+   await until(()=>gets>=2,'failed readback requested');await tick();
+   assert.equal(await select.isDisabled(),true,'uncertain selection stays locked');
+   await page.evaluate(()=>window.act('select-big'));await tick();assert.equal(writes.length,1,'programmatic second selection blocked');
+   await page.evaluate(()=>window.act('cancel'));await until(()=>writes.length===2,'cancel remains usable');
+   assert.deepEqual(writes[1],{method:'POST',path:'/api/models/cancel',body:null});
+   failReads=false;await page.evaluate(()=>window.poll());
+   await until(async()=>!(await select.isDisabled()),'authoritative retry unlocks');
+   assert.equal(await select.inputValue(),scenario.startsWith('abort')?'':'gpu-a');
+  } else {
+   await until(()=>scenario==='leave-write'?heldPut:heldGet,'held write/readback');
+   await page.evaluate(()=>{history.pushState({},'', '/elsewhere');window.leave();});await tick();
+   const before=await page.evaluate(()=>window.notices.length);
+   if(scenario==='leave-readback') active='gpu-b';
+   await page.evaluate(()=>{history.pushState({},'', '/manage_models');window.mount();});await tick();
+   if(heldPut) {
+    // A remount GET before this acceptance cannot establish the final selection.
+    active='';await heldPut.fulfill({json:{message:'selected'}});heldPut=null;
+   } else {active='gpu-b';await heldGet.route.fulfill({json:heldGet.json});heldGet=null;}
+   await tick();await tick();
+   assert.equal(await page.evaluate(()=>window.notices.length),before,'old generation must not notify');
+   await until(async()=>await select.count() && await select.inputValue()===active && !(await select.isDisabled()),'remount must read current state after pending write');
+   assert.equal(writes.length,1,'navigation must not duplicate writes');
+  }
+  assert.deepEqual(errors,[]);assert.deepEqual(unexpected,[]);
+ } catch(e) {failure=e.stack;}
+ results.push({surface,scenario,passed:!failure,failure,gets,writes,unexpected,errors});
+ if(heldGet) await heldGet.route.abort().catch(()=>{});
+ if(heldPut) await heldPut.abort().catch(()=>{});
+ await context.close();
+}
+} finally {await browser.close();}
+if(out)writeFileSync(out+'/results.json',JSON.stringify(results,null,2));
+console.log(JSON.stringify(results,null,2));
+assert.equal(results.length,10);assert.equal(results.filter(r=>!r.passed).length,0);
diff --git a/starpilot/system/the_galaxy/tests/test_model_manager_selection_browser.mjs b/starpilot/system/the_galaxy/tests/test_model_manager_selection_browser.mjs
new file mode 100644
index 0000000000..6af90932ff
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_manager_selection_browser.mjs
@@ -0,0 +1,65 @@
+const {chromium} = await import(process.env.PLAYWRIGHT_MODULE || 'playwright');
+import {fileURLToPath} from 'node:url';
+import {mkdtempSync, mkdirSync} from 'node:fs';
+import {tmpdir} from 'node:os';
+import { readFileSync, writeFileSync } from 'node:fs';
+import assert from 'node:assert/strict';
+const root = (process.env.REPO || fileURLToPath(new URL('../../../../', import.meta.url))) + '/starpilot/system/the_galaxy';
+const out = process.env.EVIDENCE || mkdtempSync(tmpdir() + '/model-manager-browser-');
+mkdirSync(out, {recursive:true});
+const browser = await chromium.launch({executablePath:process.env.BROWSER_EXECUTABLE || undefined, args:['--no-sandbox']});
+const errors = [], results = [];
+const baseline = !!process.env.BASELINE;
+try {
+ for (const surface of (process.env.MODEL_SURFACE ? [process.env.MODEL_SURFACE] : ['classic', 'mobile'])) for (const width of [1200,390]) {
+  const mobile=surface==='mobile';
+  const context=await browser.newContext({viewport:{width,height:850}});
+  let downloading=false, target='', polls=0, activeBig='fixture-0';
+  const writes=[];
+  const models=Array.from({length:36},(_,i)=>({value:`fixture-${i}`,label:`UI fixture model ${String(i).padStart(2,'0')}`,series:`Series ${i%3}`,released:`2026-08-${String(28-i%28).padStart(2,'0')}`,requiresGpu:i%2===0,gpuAvailable:true,installed:i===0 || i===2,userFavorite:i%3===0}));
+  const mount = mobile ? `import {createApp} from 'vue';import {ModelManager} from '/assets/mobile/js/views/ModelManager.js';createApp(ModelManager).mount('#app');` : `import {html} from '/assets/vendor/arrow-core.js';import {ModelManager} from '/assets/components/tools/model_manager.js';window.showSnackbar=()=>{};html\`\${()=>ModelManager()}\`(document.querySelector('#app'));`;
+  const preview=`<!doctype html><html><head><meta charset="utf-8"><link rel="stylesheet" href="/assets/vendor/bootstrap-icons/bootstrap-icons.min.css"><meta name="viewport" content="width=device-width, initial-scale=1"><link rel="stylesheet" href="${mobile?'/assets/mobile/css/material.css':'/assets/components/tools/model_manager.css'}"><script type="importmap">{"imports":{"vue":"/assets/vendor/vue/vue.esm-browser.js"}}</script><style>:root{--text-color:#e9eaf2;--text-muted:#aab0c1;--card-bg:#1b2030;--secondary-bg:#262c3c;--sidebar-border-color:#353e54;--input-bg:#171c29;--success-bg:#81d4b1;--color-black:#10251c;--danger-bg:#883644;--sidebar-active-bg:#384560;--font-size-base:14px;--padding-base:16px;--margin-base:16px;--gap-xs:4px;--gap-sm:8px;--gap-md:12px;--gap-lg:20px;--border-radius-base:8px;--border-radius-lg:12px}body{background:#101420;color:#e9eaf2;font:14px system-ui;margin:16px}*{box-sizing:border-box}</style></head><body><p style="color:#aab0c1">UI DEVELOPMENT PREVIEW — SYNTHETIC CATALOGUE, NO DEVICE CONNECTION</p><main id="app"></main><script type="module">${mount}</script></body></html>`;
+  await context.route('**/*',async route=>{
+   const url=new URL(route.request().url());
+   if(url.origin!=='http://galaxy.invalid') return route.abort();
+   if(url.pathname.startsWith('/api/')) {
+    if(route.request().method()!=='GET') {
+     writes.push({path:url.pathname,body:route.request().postDataJSON()});
+     if(url.pathname==='/api/models/active') { assert.equal(writes.at(-1).body.profile,'big'); if (!(process.env.MODEL_FAULT === 'reject' && writes.length === 1)) activeBig=writes.at(-1).body.model;
+       if (process.env.MODEL_FAULT && writes.length === 1) return route.fulfill({status:503,json:{error:'Synthetic uncertain response'}});
+     }
+     else throw new Error('Unexpected write '+url.pathname);
+     return route.fulfill({json:{message:'Synthetic UI fixture action'}});
+    }
+    assert.equal(url.pathname,'/api/models/status');polls++;
+    return route.fulfill({json:{models,currentModel:'fixture-0',activeBigModel:activeBig,activeSmallModel:'',summary:{installed:1,missing:35,total:36},downloading,modelToDownload:target,progress:downloading?`${polls}%`:'',isOnroad:false}});
+   }
+   if(url.pathname.startsWith('/assets/')) {
+    try {return route.fulfill({body:readFileSync(root+url.pathname),contentType:url.pathname.endsWith('.css')?'text/css':'text/javascript'});} catch(e) {errors.push(String(e));return route.abort();}
+   }
+   return route.fulfill({contentType:'text/html',body:preview});
+  });
+  const page=await context.newPage();page.on('pageerror',e=>{errors.push(e.message); console.error('PAGEERROR',e.message);});
+  await page.goto('http://galaxy.invalid/manage_models');
+  const rowSelector=mobile?'.gx-card-grid > section':'.mm-row';
+  const rows=page.locator(rowSelector);
+  await rows.first().waitFor();
+  const select=mobile?page.locator('.gx-row').filter({has:page.getByText('Active Big',{exact:true})}).locator('select'):page.locator('#mm-active-big-model-select');
+  assert.equal(await select.inputValue(),'fixture-0');
+  await select.selectOption('');
+  await new Promise(r=>setTimeout(r,350));
+  assert.deepEqual(writes,[{path:'/api/models/active',body:{profile:'big',model:''}}],`${surface}: None must disable Active Big through API`);
+  assert.equal(await select.inputValue(),process.env.MODEL_FAULT === 'reject' ? 'fixture-0' : '', 'Selection must match authoritative status after uncertain response');
+  if (process.env.MODEL_FAULT) assert.ok(polls >= 2, 'Uncertain write requires immediate authoritative readback');
+  await select.selectOption('fixture-2');
+  await new Promise(r=>setTimeout(r,350));
+  assert.equal(writes.length,2);
+  assert.deepEqual(writes[1],{path:'/api/models/active',body:{profile:'big',model:'fixture-2'}});
+  await page.reload();await rows.first().waitFor();
+  assert.equal(await select.inputValue(),'fixture-2');
+  results.push({surface,width,writes});
+  await context.close();
+ }
+ assert.deepEqual(errors,[]);
+ console.log(JSON.stringify({results,errors},null,2));
+} finally {await browser.close();}
diff --git a/starpilot/system/the_galaxy/tests/test_model_manager_state.mjs b/starpilot/system/the_galaxy/tests/test_model_manager_state.mjs
new file mode 100644
index 0000000000..c3bc7b54bd
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_manager_state.mjs
@@ -0,0 +1,44 @@
+// Exercise shipped component methods with deferred requests; no device I/O.
+import assert from 'node:assert/strict';
+import {readFileSync} from 'node:fs';
+const source = readFileSync(new URL('../assets/mobile/js/views/ModelManager.js', import.meta.url), 'utf8');
+const hardware = await import('../assets/components/tools/model_hardware.js');
+let status, write, prompt, requests, notices;
+const deferred = () => { let resolve, reject; const promise = new Promise((a,b)=>{resolve=a;reject=b}); return {promise,resolve,reject}; };
+const payload = (overrides={}) => ({models:[{value:'gpu',requiresGpu:true,gpuAvailable:false,installed:false},{value:'small',requiresGpu:false,installed:true}],activeBigModel:'gpu',activeSmallModel:'small',currentModel:'small',summary:{},...overrides});
+const api = {
+ getModelStatus: () => status(),
+ setActiveModel: (profile,model) => { requests.push({profile,model}); return write(); },
+ startModelDownload: (model,allow) => { requests.push({model,allow});return write(); },
+ downloadAllModels: allow => { requests.push({all:true,allow});return write(); },
+ postAction: action => { requests.push({action});return write(); },
+};
+const component = new Function('api','showSnackbar','usePolling','GalaxyConfirm','openGalaxyHelpDialog',...Object.keys(hardware), source.replace(/^import .*$/gm,'').replace('export const ModelManager', 'const ModelManager')+';return ModelManager;')(api,(...a)=>notices.push(a),()=>{},()=>{},()=>prompt(),...Object.values(hardware));
+function instance() { const vm=component.data();for(const [key,value] of Object.entries(component.methods))vm[key]=value.bind(vm);return vm; }
+async function reset() {requests=[];notices=[];status=async()=>payload();write=async()=>({});prompt=async()=>true;const vm=instance();await vm.refresh();return vm;}
+// Filters combine without altering the catalogue or selection.
+let vm=await reset();vm.hardwareFilter='comma';vm.userFilter='all';vm.communityFilter='all';assert.deepEqual(component.computed.sorted.call(vm).map(m=>m.value),['small']);assert.equal(vm.activeBigModel,'gpu');assert.deepEqual(requests,[]);
+// GPU approval is per action; cancellation sends no write and releases busy.
+prompt=async()=>false;await vm.runAction('download',vm.models[0]);assert.deepEqual(requests,[]);assert.equal(vm.busy,'');
+prompt=async()=>true;await vm.runAction('download',vm.models[0]);assert.deepEqual(requests,[{model:'gpu',allow:true}]);
+// Approval must recheck road state, competing downloads and status failures.
+for(const changed of [{isOnroad:true},{downloading:true},null]) { vm=await reset();status=changed?async()=>payload(changed):async()=>{throw Error('read failed')};await vm.runAction('download',vm.models[0]);assert.deepEqual(requests,[]);assert.equal(vm.busy,''); }
+// Ordinary downloads never reuse approval, and failed writes release busy.
+vm=await reset();write=async()=>{throw Error('download failed')};await vm.runAction('download',vm.models[1]);assert.deepEqual(requests,[{model:'small',allow:false}]);assert.equal(vm.busy,'');
+vm=await reset();await vm.runAction('downloadAll');assert.deepEqual(requests,[{all:true,allow:true}]);
+// A pre-write poll cannot overwrite authoritative post-write selection.
+vm=await reset();let old=deferred();status=()=>old.promise;let poll=vm.refresh();write=async()=>({});status=async()=>payload({activeBigModel:''});await vm.runAction('select-big');old.resolve(payload());await poll;assert.equal(vm.activeBigModel,'');assert.equal(vm.selectionUncertain,false);
+// An uncertain write plus failed readback locks only selection until retry.
+vm=await reset();write=async()=>{throw Error('uncertain write')};status=async()=>{throw Error('read failure')};await vm.runAction('select-big');assert.equal(vm.selectionUncertain,true);await vm.runAction('select-big');assert.equal(requests.length,1);await vm.runAction('cancel');assert.equal(requests.length,2);status=async()=>payload({activeBigModel:''});await vm.refresh();assert.equal(vm.selectionUncertain,false);assert.equal(vm.activeBigModel,'');
+// A remount must wait for an already sent write and ignore old notifications.
+vm=await reset();const pending=deferred();write=()=>pending.promise;const action=vm.runAction('select-big');component.beforeUnmount.call(vm);const next=instance();let reads=0;status=async()=>{reads++;return payload({activeBigModel:''})};const refreshed=next.refresh();await Promise.resolve();assert.equal(reads,0);pending.resolve({message:'old success'});await action;await refreshed;assert.equal(next.activeBigModel,'');assert.equal(next.selectionUncertain,false);assert.deepEqual(notices,[]);
+// Unmounted confirmation and overlapping action cannot submit another request.
+vm=await reset();const confirmation=deferred();prompt=()=>confirmation.promise;const downloading=vm.runAction('download',vm.models[0]);await vm.runAction('downloadAll');assert.deepEqual(requests,[]);component.beforeUnmount.call(vm);confirmation.resolve(true);await downloading;assert.deepEqual(requests,[]);
+// Two concurrent polls resolve newest-first.
+vm=await reset();const a=deferred(),b=deferred();status=()=>a.promise;const first=vm.refresh();status=()=>b.promise;const second=vm.refresh();b.resolve(payload({activeBigModel:'new'}));await second;a.resolve(payload({activeBigModel:'old'}));await first;assert.equal(vm.activeBigModel,'new');
+assert.ok(!source.includes('GalaxySelect'));assert.ok(!source.includes('model_metrics'));assert.ok(!source.includes('model_stats'));assert.ok(source.includes('selectionUncertain || status.isOnroad'));
+console.log('PASS: 15 hardware/download/selection/lifecycle scenarios against shipped methods');
+
+const {compile} = await import('../assets/vendor/vue/vue.esm-browser.js');
+assert.equal(typeof compile(component.template, {onError(error) {throw error;}}), 'function');
+console.log('PASS: shipped Vue compiler accepts the native-select Model Manager template');
diff --git a/starpilot/system/the_galaxy/tests/test_model_profile_payloads.py b/starpilot/system/the_galaxy/tests/test_model_profile_payloads.py
new file mode 100644
index 0000000000..2d5177c8b4
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_profile_payloads.py
@@ -0,0 +1,23 @@
+"""Exercise shipped Flask handler with the existing isolated Params harness."""
+import pytest
+from test_dashboard_stats import _load_server_module, FakeParams
+
+
+@pytest.mark.parametrize('payload', [
+  {'profile': 'big'}, {'profile': 'big', 'model': None},
+  {'profile': 'big', 'model': False}, {'profile': 'big', 'model': 0},
+  {'profile': 'big', 'model': []}, {'profile': 'big', 'model': {}},
+  [], ['big'], True, 1,
+])
+def test_malformed_selection_never_disables_big(monkeypatch, payload):
+  server = _load_server_module()
+  assert server._import_galaxy_web_symbols()
+  app = server.Flask('model_payload_test')
+  server.setup(app)
+  params = FakeParams({'IsOnroad': False, 'ActiveBigModel': 'installed-big',
+                       'ActiveBigModelName': 'Installed Big', 'ActiveBigModelVersion': 'v16'})
+  monkeypatch.setattr(server, 'params', params)
+  before = params.values.copy()
+  response = app.test_client().put('/api/models/active', json=payload)
+  assert response.status_code == 400
+  assert params.values == before
diff --git a/starpilot/system/the_galaxy/tests/test_model_selection_contract.py b/starpilot/system/the_galaxy/tests/test_model_selection_contract.py
new file mode 100644
index 0000000000..88ae9099d0
--- /dev/null
+++ b/starpilot/system/the_galaxy/tests/test_model_selection_contract.py
@@ -0,0 +1,16 @@
+"""Actual Flask Active Big contract with in-memory Params, no native/device I/O."""
+import pytest
+from test_personality_profiles_api import _client, the_galaxy
+
+@pytest.mark.parametrize('profile,onroad,expected', [('big',False,200),('small',False,400),('big',True,403),('invalid',False,400)])
+def test_active_big_empty_contract(monkeypatch, profile, onroad, expected):
+  client, params = _client(monkeypatch, {'IsOnroad':onroad})
+  calls=[]
+  monkeypatch.setattr(the_galaxy,'disable_big_model_profile',lambda p:calls.append(p))
+  monkeypatch.setattr(the_galaxy,'normalize_model_lab_config',lambda raw:{'enabled':False})
+  response=client.put('/api/models/active',json={'profile':profile,'model':''})
+  assert response.status_code == expected, response.get_json()
+  assert len(calls) == (expected == 200)
+  if expected == 200:
+    assert response.get_json()['model'] == ''
+    assert response.get_json()['profile'] == 'big'
diff --git a/starpilot/system/the_galaxy/the_galaxy.py b/starpilot/system/the_galaxy/the_galaxy.py
index 9f2176aa0d..eecd23f4cd 100644
--- a/starpilot/system/the_galaxy/the_galaxy.py
+++ b/starpilot/system/the_galaxy/the_galaxy.py
@@ -5171,6 +5171,8 @@ class GalaxySlugMiddleware:
 
 
 def setup(app):
+  from openpilot.starpilot.assets.model_sizes import ModelSizes
+  model_sizes = ModelSizes()
   if not isinstance(app.wsgi_app, GalaxySlugMiddleware):
     app.wsgi_app = GalaxySlugMiddleware(app.wsgi_app)
 
@@ -6887,7 +6889,10 @@ def setup(app):
     if params.get_bool("IsOnroad"):
       return jsonify({"error": "Cannot change active models while driving."}), 403
 
-    data = request.get_json(silent=True) or {}
+    data = request.get_json(silent=True)
+    # An explicit empty model disables Active Big; malformed values must not.
+    if not isinstance(data, dict) or not isinstance(data.get("model"), str):
+      return jsonify({"error": "An explicit model string is required."}), 400
     profile = str(data.get("profile") or "").strip().lower()
     if profile not in ("small", "big"):
       return jsonify({"error": "Model profile must be 'small' or 'big'."}), 400
@@ -7529,7 +7534,9 @@ def setup(app):
       })
 
     models.sort(key=lambda model: (model["series"].lower(), model["label"].lower()))
-    return models
+    return model_sizes.annotate(models, MODELS_PATH,
+                                Path(__file__).resolve().parents[3] / "selfdrive/modeld/models/driving_tinygrad.pkl",
+                                artifact_metadata, model_accelerator_artifact_filename)
 
   @app.route("/api/routes", methods=["GET"])
   def list_routes():