feat: add provider availability detection and normalize legacy "default" model IDs

packages/app/src/utils/extract-agent-model.test.ts

@@ -19,4 +19,13 @@ describe("extractAgentModel", () => {
 
     expect(extractAgentModel(agent)).toBe("gpt-5.1-codex");
   });
+
+  it("treats legacy 'default' model ids as unset", () => {
+    const agent = {
+      model: "default",
+      runtimeInfo: { model: "default" },
+    } as Partial<Agent> as Agent;
+
+    expect(extractAgentModel(agent)).toBeNull();
+  });
 });

packages/app/src/utils/extract-agent-model.ts

@@ -4,11 +4,17 @@ export function extractAgentModel(agent?: Agent | null): string | null {
   if (!agent) return null;
   const runtimeModel = agent.runtimeInfo?.model;
   const fallbackModel = agent.model;
-  if (typeof runtimeModel === "string" && runtimeModel.trim().length > 0) {
-    return runtimeModel.trim();
+  if (typeof runtimeModel === "string") {
+    const normalized = runtimeModel.trim();
+    if (normalized.length > 0 && normalized.toLowerCase() !== "default") {
+      return normalized;
+    }
   }
-  if (typeof fallbackModel === "string" && fallbackModel.trim().length > 0) {
-    return fallbackModel.trim();
+  if (typeof fallbackModel === "string") {
+    const normalized = fallbackModel.trim();
+    if (normalized.length > 0 && normalized.toLowerCase() !== "default") {
+      return normalized;
+    }
   }
   return null;
 }