diff --git a/tests/test_console_available_models.py b/tests/test_console_available_models.py
index caf331e9..b058c338 100644
--- a/tests/test_console_available_models.py
+++ b/tests/test_console_available_models.py
@@ -67,6 +67,7 @@ def _make_client(
     storage: SQLiteBackend,
     *,
     settings: dict[str, str] | None = None,
+    registry_default: str | None = None,
 ) -> TestClient:
     app = Starlette(
         routes=[Route("/v1/api/models", list_available_models)],
@@ -74,6 +75,12 @@ def _make_client(
     )
     app.state.auth_storage = storage
     app.state.config_store = _FakeConfigStore(dict(settings or {}))
+    if registry_default is not None:
+        # Mimic the live console's ``coord_registry`` shape — the handler
+        # only reads ``.default``, so a SimpleNamespace is enough.
+        from types import SimpleNamespace
+
+        app.state.coord_registry = SimpleNamespace(default=registry_default)
     client = TestClient(app)
     client.headers.update({"X-Test-User": "admin", "X-Test-Perms": ""})
     return client
@@ -165,6 +172,34 @@ def test_coordinator_set_to_unknown_alias_falls_back_to_default(
     assert body["coordinator_default_alias"] == "primary"
 
 
+def test_coordinator_falls_back_to_registry_default_when_config_store_empty(
+    storage: SQLiteBackend,
+) -> None:
+    """Match ``console/session_factory.py:109-110``: when both
+    ``coordinator.model_alias`` and ``model.default_alias`` are unset, new
+    coordinator sessions run on ``registry.default`` (loaded from
+    config.toml ``[model].default``).  The placeholder must report the
+    same alias rather than going blank — otherwise the home composer
+    advertises "Default model" while sessions actually launch on a
+    concrete alias."""
+    _seed_model(storage, definition_id="m1", alias="primary")
+    body = _get_models(_make_client(storage, registry_default="primary"))
+    assert body["default_alias"] == ""
+    assert body["coordinator_default_alias"] == "primary"
+    assert body["judge_default_alias"] == "primary"
+
+
+def test_coordinator_skips_registry_default_when_alias_disabled(
+    storage: SQLiteBackend,
+) -> None:
+    """Registry default points at an alias that's been disabled in the DB
+    — the placeholder stays blank rather than advertising a model that
+    workstream creation would refuse to use."""
+    _seed_model(storage, definition_id="m1", alias="legacy", enabled=False)
+    body = _get_models(_make_client(storage, registry_default="legacy"))
+    assert body["coordinator_default_alias"] == ""
+
+
 # ---------------------------------------------------------------------------
 # Judge resolution
 # ---------------------------------------------------------------------------
diff --git a/turnstone/console/server.py b/turnstone/console/server.py
index 584b9ce8..33648fd5 100644
--- a/turnstone/console/server.py
+++ b/turnstone/console/server.py
@@ -1684,15 +1684,25 @@ async def list_available_models(request: Request) -> JSONResponse:
         default_alias = ""
     if channel_default_alias and channel_default_alias not in enabled_aliases:
         channel_default_alias = ""
-    # Coordinator falls back to model.default_alias when its setting is
-    # empty or points at a disabled/removed alias (matches
-    # console/session_factory.py).  Judge falls back to the resolved
-    # coordinator alias when judge.model is empty *or* not a registered
-    # alias — judge.model is alias-only (matches IntentJudge.__init__),
-    # so an unknown value is operator misconfiguration that the judge
-    # itself silently inherits the session model on.
+    # Coordinator fallback chain mirrors console/session_factory.py:109-110:
+    # explicit ``coordinator.model_alias`` → ``model.default_alias``
+    # (admin-managed) → ``registry.default`` (the config.toml default that
+    # session_factory falls through to via ``registry.default`` when both
+    # ConfigStore keys are unset).  Without the registry tier the
+    # placeholder lies whenever an operator never set ``model.default_alias``
+    # in the admin UI — new coordinator sessions will still run on
+    # ``registry.default``.  Judge falls back to the resolved coordinator
+    # alias when ``judge.model`` is empty *or* not a registered alias —
+    # judge.model is alias-only (matches IntentJudge.__init__), so an
+    # unknown value is operator misconfiguration that the judge itself
+    # silently inherits the session model on.
     if not coordinator_default_alias or coordinator_default_alias not in enabled_aliases:
         coordinator_default_alias = default_alias
+    if not coordinator_default_alias:
+        coord_registry = getattr(request.app.state, "coord_registry", None)
+        registry_default = getattr(coord_registry, "default", "") if coord_registry else ""
+        if registry_default and registry_default in enabled_aliases:
+            coordinator_default_alias = registry_default
     if not judge_default_alias or judge_default_alias not in enabled_aliases:
         judge_default_alias = coordinator_default_alias
     return JSONResponse(
diff --git a/turnstone/console/static/app.js b/turnstone/console/static/app.js
index 04979434..3506b4be 100644
--- a/turnstone/console/static/app.js
+++ b/turnstone/console/static/app.js
@@ -1813,7 +1813,7 @@ function _resolveModelLabel(alias, models) {
       return m.alias === m.model ? m.alias : m.alias + " (" + m.model + ")";
     }
   }
-  return alias;
+  return "";
 }
 
 // Populate Model + Judge Model dropdowns from /v1/api/models — same