fix(tui): surface model errors

src/agents/pi-embedded-helpers.formatrawassistanterrorforui.test.ts

@@ -0,0 +1,21 @@
+import { describe, expect, it } from "vitest";
+
+import { formatRawAssistantErrorForUi } from "./pi-embedded-helpers.js";
+
+describe("formatRawAssistantErrorForUi", () => {
+  it("renders HTTP code + type + message from Anthropic payloads", () => {
+    const text = formatRawAssistantErrorForUi(
+      '429 {"type":"error","error":{"type":"rate_limit_error","message":"Rate limited."},"request_id":"req_123"}',
+    );
+
+    expect(text).toContain("HTTP 429");
+    expect(text).toContain("rate_limit_error");
+    expect(text).toContain("Rate limited.");
+    expect(text).toContain("req_123");
+  });
+
+  it("renders a generic unknown error message when raw is empty", () => {
+    expect(formatRawAssistantErrorForUi("")).toContain("unknown error");
+  });
+});
+