diff --git a/src/oauth-vault.ts b/src/oauth-vault.ts
index 80cb8fa..1a41201 100644
--- a/src/oauth-vault.ts
+++ b/src/oauth-vault.ts
@@ -6,8 +6,6 @@ import type { OAuthClientInformationMixed, OAuthTokens } from '@modelcontextprot
 import type { ServerDefinition } from './config.js';
 import { readJsonFile, writeJsonFile } from './fs-json.js';
 
-const VAULT_PATH = path.join(os.homedir(), '.mcporter', 'credentials.json');
-
 type VaultKey = string;
 
 export interface VaultEntry {
@@ -25,10 +23,14 @@ interface VaultFile {
   entries: Record<VaultKey, VaultEntry>;
 }
 
+function vaultPath(): string {
+  return path.join(os.homedir(), '.mcporter', 'credentials.json');
+}
+
 async function readVault(): Promise<VaultFile> {
   let shouldRewrite = false;
   try {
-    const existing = await readJsonFile<VaultFile>(VAULT_PATH);
+    const existing = await readJsonFile<VaultFile>(vaultPath());
     if (existing && existing.version === 1 && existing.entries && typeof existing.entries === 'object') {
       return existing;
     }
@@ -46,9 +48,10 @@ async function readVault(): Promise<VaultFile> {
 }
 
 async function writeVault(contents: VaultFile): Promise<void> {
-  const dir = path.dirname(VAULT_PATH);
+  const filePath = vaultPath();
+  const dir = path.dirname(filePath);
   await fs.mkdir(dir, { recursive: true });
-  await writeJsonFile(VAULT_PATH, contents);
+  await writeJsonFile(filePath, contents);
 }
 
 export function vaultKeyForDefinition(definition: ServerDefinition): VaultKey {
diff --git a/tests/cli-call-errors.test.ts b/tests/cli-call-errors.test.ts
index 2e5ab3a..982d8b9 100644
--- a/tests/cli-call-errors.test.ts
+++ b/tests/cli-call-errors.test.ts
@@ -24,4 +24,27 @@ describe('CLI call error reporting', () => {
     logSpy.mockRestore();
     errorSpy.mockRestore();
   });
+
+  it('emits structured http envelopes for non-auth transport failures', async () => {
+    const { handleCall } = await cliModulePromise;
+    const callTool = vi.fn().mockRejectedValue(new Error('SSE error: Non-200 status code (410)'));
+    const runtime = {
+      callTool,
+      close: vi.fn().mockResolvedValue(undefined),
+    } as unknown as Awaited<ReturnType<typeof import('../src/runtime.js')['createRuntime']>>;
+
+    const logSpy = vi.spyOn(console, 'log').mockImplementation(() => {});
+    const errorSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+
+    await handleCall(runtime, ['deepwiki.read_wiki_structure', '--output', 'json']);
+
+    const payload = JSON.parse(logSpy.mock.calls.at(-1)?.[0] ?? '{}');
+    expect(payload.issue?.kind).toBe('http');
+    expect(payload.issue?.statusCode).toBe(410);
+    expect(payload.tool).toBe('read_wiki_structure');
+    expect(errorSpy.mock.calls.some((call) => call.join(' ').includes('responded with HTTP 410'))).toBe(true);
+
+    logSpy.mockRestore();
+    errorSpy.mockRestore();
+  });
 });
diff --git a/tests/cli-output-utils.test.ts b/tests/cli-output-utils.test.ts
index 6364c2a..4faebf5 100644
--- a/tests/cli-output-utils.test.ts
+++ b/tests/cli-output-utils.test.ts
@@ -116,6 +116,14 @@ describe('printCallOutput format selection', () => {
         expect(String(logged)).toContain("type: 'json'");
       },
     ],
+    [
+      'auto falls back to readable raw output for plain object payloads',
+      'auto',
+      { result: 'Available pages for facebook/react' },
+      (logged: unknown) => {
+        expect(String(logged)).toContain("result: 'Available pages for facebook/react'");
+      },
+    ],
   ] as const)('%s', (_name, format, raw, assertLogged) => {
     const wrapped = createCallResult(raw);
     const log = vi.spyOn(console, 'log').mockImplementation(() => {});
diff --git a/vitest.config.ts b/vitest.config.ts
index f494188..d25f57e 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -14,5 +14,8 @@ export default defineConfig({
     // Quiet mode hides console output for passing tests so CLI fixture logs
     // (e.g., the full `mcporter list` banners) don't overwhelm the reporter.
     ...quietReporterOptions,
+    // CLI-heavy suites import the full entrypoint in parallel and can exceed the
+    // default 5s timeout under local load even when behavior is correct.
+    testTimeout: 10_000,
   },
 });