diff --git a/packages/deploy/src/login.test.ts b/packages/deploy/src/login.test.ts
index e55bcfb4..cb4ad010 100644
--- a/packages/deploy/src/login.test.ts
+++ b/packages/deploy/src/login.test.ts
@@ -141,6 +141,27 @@ test('resolveWorkspaceToken fails clearly when workspace resolve returns non-JSO
   });
 });
 
+test('resolveWorkspaceToken surfaces stale-workspace guidance on 404', async () => {
+  await withCloudSessionEnv(async () => {
+    const restoreFetch = withTrappedFetch(async () =>
+      new Response('Workspace not found', { status: 404 })
+    );
+    try {
+      await assert.rejects(
+        resolveWorkspaceToken({
+          workspace: 'rw_stale',
+          cloudUrl: 'https://cloud.example.test',
+          io: createBufferedIO(),
+          noPrompt: true
+        }),
+        /agent-relay workspace list.*agent-relay workspace switch/s
+      );
+    } finally {
+      restoreFetch();
+    }
+  });
+});
+
 test('resolveWorkspaceToken without a cloud session fails with login guidance', () => {
   const home = mkdtempSync(path.join(os.tmpdir(), 'wf-no-cloud-session-'));
   const env: NodeJS.ProcessEnv = {
diff --git a/packages/deploy/src/login.ts b/packages/deploy/src/login.ts
index b7187678..b0d4229b 100644
--- a/packages/deploy/src/login.ts
+++ b/packages/deploy/src/login.ts
@@ -158,6 +158,8 @@ async function resolveWorkspaceDescriptor(args: {
     return resolveActiveWorkspace({
       apiUrl: args.apiUrl,
       interactive: false
+    }).catch((error) => {
+      throw workspaceNotFoundError(error, undefined);
     });
   }
 
@@ -171,12 +173,38 @@ async function resolveWorkspaceDescriptor(args: {
   );
   if (!response.ok) {
     const text = await response.text().catch(() => '');
-    throw new Error(`workspace resolve failed for ${workspace}: ${response.status} ${text}`.trim());
+    throw workspaceNotFoundError(
+      new Error(`workspace resolve failed for ${workspace}: ${response.status} ${text}`.trim()),
+      workspace,
+      response.status
+    );
   }
   const payload = await response.json().catch(() => null);
   return normalizeWorkspaceDescriptor(payload, session.auth.apiUrl || args.apiUrl);
 }
 
+/**
+ * The active-workspace pointer stored locally (`agent-relay workspace switch`)
+ * can go stale if the workspace was deleted or expired server-side; the raw
+ * 404 from @agent-relay/cloud gives no hint that the *fix* is to re-pick a
+ * workspace rather than retry. Detect that case and append actionable guidance.
+ */
+function workspaceNotFoundError(error: unknown, workspace: string | undefined, status?: number): Error {
+  const message = error instanceof Error ? error.message : String(error);
+  const is404 = status === 404 || /:\s*404\b/.test(message) || /workspace not found/i.test(message);
+  if (!is404) {
+    return error instanceof Error ? error : new Error(message);
+  }
+  const diagnosis = workspace
+    ? `workspace "${workspace}" was not found server-side (deleted, expired, revoked, or never provisioned).`
+    : 'the active workspace was not found server-side (deleted, expired, or never provisioned) — the local workspace pointer is stale.';
+  return new Error(
+    `${message}\n\n${diagnosis} ` +
+      'Run `agent-relay workspace list` to see valid workspaces, then `agent-relay workspace switch <name>` to pick one, ' +
+      'or `agentworkforce deploy --mode cloud` to provision a new one.'
+  );
+}
+
 function normalizeWorkspaceDescriptor(payload: unknown, apiUrl: string): ActiveWorkspaceDescriptor {
   if (!payload || typeof payload !== 'object' || Array.isArray(payload)) {
     throw new Error('workspace resolve returned an invalid descriptor');