Handle preflight model-list transport failures

Wrap the auth+listModelIds preflight so a throw (e.g. a transient 5xx from
Cursor.models.list after auth succeeds) returns EXIT.TRANSPORT with a clean
JSON result instead of an unhandled rejection that crashed with no stdout.
Add a CLI entrypoint .catch backstop. Found by the final whole-branch review.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: baonguyenNava

strata-qa/src/cli.ts

@@ -139,5 +139,12 @@ if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href)
   main(process.argv.slice(2), {
     out: (s) => process.stdout.write(s),
     err: (s) => process.stderr.write(s),
-  }).then((code) => process.exit(code));
+  })
+    .then((code) => process.exit(code))
+    // Backstop: any unexpected throw still exits non-zero (never a silent unhandled
+    // rejection), preserving the "operational failures exit non-zero" contract.
+    .catch((e) => {
+      process.stderr.write(`fatal: ${String(e)}\n`);
+      process.exit(EXIT.TRANSPORT);
+    });
 }

strata-qa/src/run.test.ts

@@ -108,6 +108,21 @@ describe("runQa", () => {
     expect(out.errorMessage).toContain("sonnet-4");
   });
 
+  test("listModelIds throws (post-auth transport failure) -> exit 7, status error, no crash", async () => {
+    const root = makeDocsRoot();
+    const out = await runQa(
+      opts(root, join(root, "logs")),
+      fakeSeam({
+        listModelIds: async () => {
+          throw new Error("models.list 503");
+        },
+      }),
+    );
+    expect(out.exitCode).toBe(EXIT.TRANSPORT);
+    expect(out.result.status).toBe("error");
+    expect(out.errorMessage).toContain("models.list 503");
+  });
+
   test("missing docs root files -> exit 4", async () => {
     const empty = mkdtempSync(join(tmpdir(), "strata-qa-empty-"));
     const out = await runQa(opts(empty, join(empty, "logs")), fakeSeam());

strata-qa/src/run.ts

@@ -106,14 +106,26 @@ export async function runQa(opts: RunOptions, seam: AgentSeam): Promise<RunOutco
   const logDir = opts.logDir ?? join(".logs", "qa");
 
   // Preflight — fail loud with a distinct exit code per failure mode.
-  if (!(await seam.checkAuth())) {
+  // A THROW from the auth/list SDK calls (e.g. a transient 5xx after auth) maps
+  // to TRANSPORT so the exit-code + single-JSON contract holds; checkAuth
+  // returning false is the distinct AUTH case.
+  let ids: string[];
+  try {
+    if (!(await seam.checkAuth())) {
+      return {
+        result: errorResult(model, "", null, null),
+        exitCode: EXIT.AUTH,
+        errorMessage: "CURSOR_API_KEY missing or failed to authenticate",
+      };
+    }
+    ids = await seam.listModelIds();
+  } catch (e) {
     return {
       result: errorResult(model, "", null, null),
-      exitCode: EXIT.AUTH,
-      errorMessage: "CURSOR_API_KEY missing or failed to authenticate",
+      exitCode: EXIT.TRANSPORT,
+      errorMessage: `preflight failed contacting the model API: ${String(e)}`,
     };
   }
-  const ids = await seam.listModelIds();
   if (!ids.includes(model)) {
     return {
       result: errorResult(model, "", null, null),