feat(agent): let users choose model route

src/app/api/agent/models/route.ts

@@ -1,7 +1,7 @@
 import { apiError, apiJson } from "@/lib/api-handler";
 import { resolveApiAuth } from "@/lib/api-auth";
 import { getAssistantPreferences } from "@/lib/assistant-preference";
-import { listLlmModels, resolveAssistantModel } from "@/lib/llm/models";
+import { isValidAssistantModelRoute, listLlmModels, resolveAssistantModel } from "@/lib/llm/models";
 
 export const dynamic = "force-dynamic";
 
@@ -21,10 +21,16 @@ export async function GET(request: Request) {
     return noStore(apiError("Assistant not enabled", 403));
   }
 
-  const modelList = await listLlmModels();
+  const requestedRoute = new URL(request.url).searchParams.get("route");
+  if (requestedRoute !== null && !isValidAssistantModelRoute(requestedRoute)) {
+    return noStore(apiError("Invalid assistant model route", 400));
+  }
+
+  const modelRoute = requestedRoute ?? assistant.modelRoute;
+  const modelList = await listLlmModels({ route: modelRoute });
   const resolved = resolveAssistantModel({
     requestedModel: null,
-    savedModel: assistant.model,
+    savedModel: requestedRoute === null ? assistant.model : null,
     fallbackModel: modelList.fallbackModel,
     models: modelList.models,
   });
@@ -34,6 +40,7 @@ export async function GET(request: Request) {
       models: modelList.models,
       selectedModel: resolved.model,
       fallbackModel: modelList.fallbackModel,
+      route: modelList.route,
       degraded: modelList.degraded,
     }),
   );