feat(models): show LangBot Models availability

src/langbot/pkg/api/http/controller/groups/system.py

@@ -220,6 +220,21 @@ class SystemRouterGroup(group.RouterGroup):
                 return self.http_status(503, -1, str(exc))
             return self.success(data=model)
 
+        @self.route(
+            '/model-availability',
+            methods=['GET'],
+            auth_type=group.AuthType.USER_TOKEN,
+            permission=Permission.RESOURCE_VIEW,
+        )
+        async def _(request_context: RequestContext) -> str:
+            """Expose Space's latest persisted model probes to the WebUI."""
+            try:
+                models = await self.ap.space_service.get_model_selection()
+            except Exception as exc:
+                self.ap.logger.warning(f'Failed to load LangBot Models availability: {exc}')
+                return self.http_status(503, -1, 'Model availability is unavailable')
+            return self.success(data={'models': [model.model_dump(mode='json') for model in models]})
+
         @self.route(
             '/tasks',
             methods=['GET'],

src/langbot/pkg/api/http/service/space.py

@@ -242,13 +242,14 @@ class SpaceService:
             models_data = data.get('data', {}).get('models', [])
             return [SpaceModel.model_validate(model_dict) for model_dict in models_data]
 
-    async def get_model_selection(self, category: str) -> typing.List[SpaceModelSelection]:
+    async def get_model_selection(self, category: str | None = None) -> typing.List[SpaceModelSelection]:
         """Return Space models in the availability-ranked selection order."""
         space_url = self._get_space_config()['url']
         session = httpclient.get_session()
+        params = {'category': category} if category else None
         async with session.get(
             f'{space_url}/api/v1/models/selection',
-            params={'category': category},
+            params=params,
         ) as response:
             if response.status != 200:
                 error = await httpclient.read_text_limited(response)
@@ -266,7 +267,17 @@ class SpaceService:
             models = []
             for selection in data:
                 if isinstance(selection, dict) and isinstance(selection.get('model'), dict):
-                    models.append(selection['model'])
+                    model = dict(selection['model'])
+                    availability = selection.get('availability')
+                    if not isinstance(availability, dict):
+                        # Accept the short-lived pre-release response shape.
+                        availability = {
+                            key: selection[key]
+                            for key in ('up', 'last_probed_at', 'latency_ms', 'http_code')
+                            if key in selection
+                        }
+                    model['availability'] = availability
+                    models.append(model)
                 else:
                     models.append(selection)
             return [SpaceModelSelection.model_validate(model) for model in models]

src/langbot/pkg/entity/dto/space_model.py

@@ -49,8 +49,19 @@ class SpaceModel(pydantic.BaseModel):
     updated_at: str | None = None
 
 
+class SpaceModelAvailability(pydantic.BaseModel):
+    """Latest availability probe. ``up`` is None when no probe exists."""
+
+    up: bool | None = None
+    last_probed_at: str | None = None
+    latency_ms: int = 0
+    http_code: int = 0
+
+
 class SpaceModelSelection(pydantic.BaseModel):
-    """Minimal model identity returned by the ranked selection endpoint."""
+    """Model identity and the latest persisted probe from Space."""
 
     uuid: str
     model_id: str
+    category: str | None = None
+    availability: SpaceModelAvailability = pydantic.Field(default_factory=SpaceModelAvailability)