diff --git a/__tests__/api/cloud/sandbox-service.test.ts b/__tests__/api/cloud/sandbox-service.test.ts
new file mode 100644
index 0000000000..c46478e61a
--- /dev/null
+++ b/__tests__/api/cloud/sandbox-service.test.ts
@@ -0,0 +1,56 @@
+import axios from "axios";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import {
+  __resetActiveStoreForTests,
+  setActiveSelection,
+  setRegisteredBackends,
+} from "#/api/backend-registry/active-store";
+import { batchGetCloudSandboxes } from "#/api/cloud/sandbox-service.api";
+import type { Backend } from "#/api/backend-registry/types";
+
+vi.mock("axios");
+
+const cloudBackend: Backend = {
+  id: "cloud-prod",
+  name: "Production",
+  host: "https://app.all-hands.dev",
+  apiKey: "bearer-token",
+  kind: "cloud",
+};
+
+beforeEach(() => {
+  window.localStorage.clear();
+  __resetActiveStoreForTests();
+  setRegisteredBackends([cloudBackend]);
+  setActiveSelection({ backendId: cloudBackend.id });
+  vi.mocked(axios.post).mockReset();
+  vi.mocked(axios.post).mockResolvedValue({ data: [] });
+});
+
+afterEach(() => {
+  window.localStorage.clear();
+  __resetActiveStoreForTests();
+  vi.mocked(axios.post).mockReset();
+});
+
+describe("batchGetCloudSandboxes", () => {
+  it("targets /api/v1/sandboxes with one id query param per sandbox id", async () => {
+    // Arrange — multiple ids exercises the URLSearchParams.append path,
+    // which is the SaaS contract for batch-fetching sandboxes (the GUI
+    // reads sandbox.exposed_urls from the response to find the VSCODE
+    // URL instead of asking the runtime for a localhost address).
+    const ids = ["sandbox-a", "sandbox-b"];
+
+    // Act
+    await batchGetCloudSandboxes(ids);
+
+    // Assert — the cloud-proxy envelope encodes a GET against
+    // /api/v1/sandboxes?id=sandbox-a&id=sandbox-b on the SaaS.
+    const [, body] = vi.mocked(axios.post).mock.calls[0]!;
+    const upstream = body as { method: string; path: string };
+    expect(upstream.method).toBe("GET");
+    expect(upstream.path).toBe(
+      "/api/v1/sandboxes?id=sandbox-a&id=sandbox-b",
+    );
+  });
+});
diff --git a/__tests__/hooks/use-unified-vscode-url.test.tsx b/__tests__/hooks/use-unified-vscode-url.test.tsx
new file mode 100644
index 0000000000..eae7ab0ebc
--- /dev/null
+++ b/__tests__/hooks/use-unified-vscode-url.test.tsx
@@ -0,0 +1,202 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { renderHook, waitFor } from "@testing-library/react";
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+import { I18nextProvider } from "react-i18next";
+import i18n from "i18next";
+import { initReactI18next } from "react-i18next";
+import React from "react";
+import { useUnifiedVSCodeUrl } from "#/hooks/query/use-unified-vscode-url";
+import { batchGetCloudSandboxes } from "#/api/cloud/sandbox-service.api";
+import AgentServerConversationService from "#/api/conversation-service/agent-server-conversation-service.api";
+import ConversationService from "#/api/conversation-service/conversation-service.api";
+import { useActiveBackend } from "#/contexts/active-backend-context";
+import { useActiveConversation } from "#/hooks/query/use-active-conversation";
+import { useRuntimeIsReady } from "#/hooks/use-runtime-is-ready";
+import type { ResolvedActiveBackend } from "#/api/backend-registry/types";
+import type { V1SandboxInfo } from "#/api/cloud/sandbox-service.types";
+import type { AppConversation } from "#/api/conversation-service/agent-server-conversation-service.types";
+
+vi.mock("#/api/cloud/sandbox-service.api");
+vi.mock("#/api/conversation-service/agent-server-conversation-service.api");
+vi.mock("#/api/conversation-service/conversation-service.api");
+vi.mock("#/contexts/active-backend-context");
+vi.mock("#/hooks/query/use-active-conversation");
+vi.mock("#/hooks/use-runtime-is-ready");
+vi.mock("#/hooks/use-conversation-id", () => ({
+  useConversationId: () => ({ conversationId: "conv-123" }),
+}));
+
+if (!i18n.isInitialized) {
+  i18n.use(initReactI18next).init({
+    lng: "en",
+    fallbackLng: "en",
+    ns: ["openhands"],
+    defaultNS: "openhands",
+    resources: { en: { openhands: {} } },
+    interpolation: { escapeValue: false },
+    returnEmptyString: false,
+  });
+}
+
+const cloudBackend: ResolvedActiveBackend = {
+  backend: {
+    id: "cloud-prod",
+    name: "Production",
+    host: "https://app.all-hands.dev",
+    apiKey: "key",
+    kind: "cloud",
+  },
+  orgId: "org-1",
+};
+
+const localBackend: ResolvedActiveBackend = {
+  backend: {
+    id: "local-1",
+    name: "Local",
+    host: "http://localhost:8000",
+    apiKey: "key",
+    kind: "local",
+  },
+  orgId: null,
+};
+
+function makeConversation(
+  overrides: Partial<AppConversation> = {},
+): AppConversation {
+  return {
+    id: "conv-123",
+    sandbox_id: "sandbox-9",
+    conversation_url: "http://abc.staging-runtime.all-hands.dev/api/conv/1",
+    session_api_key: "sek",
+    created_by_user_id: null,
+    selected_repository: null,
+    selected_branch: null,
+    git_provider: null,
+    title: null,
+    trigger: null,
+    pr_number: [],
+    llm_model: null,
+    metrics: null,
+    created_at: "2026-05-12T00:00:00Z",
+    updated_at: "2026-05-12T00:00:00Z",
+    execution_status: "running",
+    sub_conversation_ids: [],
+    ...overrides,
+  } as AppConversation;
+}
+
+function makeSandbox(
+  overrides: Partial<V1SandboxInfo> = {},
+): V1SandboxInfo {
+  return {
+    id: "sandbox-9",
+    created_by_user_id: null,
+    sandbox_spec_id: "spec-1",
+    status: "RUNNING",
+    session_api_key: "sek",
+    exposed_urls: [
+      {
+        name: "VSCODE",
+        url: "https://vscode-abc.staging-runtime.all-hands.dev/?tkn=sek&folder=%2Fworkspace%2Fproject",
+      },
+    ],
+    created_at: "2026-05-12T00:00:00Z",
+    ...overrides,
+  };
+}
+
+function createWrapper() {
+  const queryClient = new QueryClient({
+    defaultOptions: { queries: { retry: false } },
+  });
+  return ({ children }: { children: React.ReactNode }) => (
+    <QueryClientProvider client={queryClient}>
+      <I18nextProvider i18n={i18n}>{children}</I18nextProvider>
+    </QueryClientProvider>
+  );
+}
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  vi.mocked(useRuntimeIsReady).mockReturnValue(true);
+  vi.mocked(useActiveConversation).mockReturnValue({
+    data: makeConversation(),
+  } as unknown as ReturnType<typeof useActiveConversation>);
+});
+
+afterEach(() => {
+  vi.clearAllMocks();
+});
+
+describe("useUnifiedVSCodeUrl", () => {
+  it("returns the SaaS-computed VSCode URL from sandbox.exposed_urls in cloud mode", async () => {
+    // Arrange — cloud backend, sandbox returned with a VSCODE entry.
+    // This is the steady-state happy path: the SaaS pre-builds the
+    // public vscode subdomain URL and the GUI must surface it directly
+    // instead of asking the runtime for /api/vscode/url (which only
+    // knows its own localhost:8001).
+    vi.mocked(useActiveBackend).mockReturnValue(cloudBackend);
+    vi.mocked(batchGetCloudSandboxes).mockResolvedValue([makeSandbox()]);
+
+    // Act
+    const { result } = renderHook(() => useUnifiedVSCodeUrl(), {
+      wrapper: createWrapper(),
+    });
+
+    // Assert
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(result.current.data?.url).toBe(
+      "https://vscode-abc.staging-runtime.all-hands.dev/?tkn=sek&folder=%2Fworkspace%2Fproject",
+    );
+    expect(
+      AgentServerConversationService.getVSCodeUrl,
+    ).not.toHaveBeenCalled();
+  });
+
+  it("returns null url in cloud mode when the sandbox has no VSCODE exposed_url", async () => {
+    // Arrange — sandbox is reachable but isn't running yet (STARTING /
+    // PAUSED), so exposed_urls hasn't been populated. The hook must
+    // surface "no URL" gracefully so the tab shows the empty-state
+    // copy instead of crashing or serving a localhost fallback.
+    vi.mocked(useActiveBackend).mockReturnValue(cloudBackend);
+    vi.mocked(batchGetCloudSandboxes).mockResolvedValue([
+      makeSandbox({ status: "STARTING", exposed_urls: null }),
+    ]);
+
+    // Act
+    const { result } = renderHook(() => useUnifiedVSCodeUrl(), {
+      wrapper: createWrapper(),
+    });
+
+    // Assert
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(result.current.data?.url).toBeNull();
+  });
+
+  it("falls through to AgentServerConversationService.getVSCodeUrl in local mode", async () => {
+    // Arrange — local backend: cloud sandbox lookup must be skipped and
+    // the existing local resolver must drive the URL. Regression check
+    // for the cloud/local branch that was added to the hook.
+    vi.mocked(useActiveBackend).mockReturnValue(localBackend);
+    vi.mocked(AgentServerConversationService.getVSCodeUrl).mockResolvedValue({
+      vscode_url: "http://localhost:8001/?tkn=local-key&folder=workspace",
+    });
+
+    // Act
+    const { result } = renderHook(() => useUnifiedVSCodeUrl(), {
+      wrapper: createWrapper(),
+    });
+
+    // Assert
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(
+      AgentServerConversationService.getVSCodeUrl,
+    ).toHaveBeenCalledWith(
+      "conv-123",
+      "http://abc.staging-runtime.all-hands.dev/api/conv/1",
+      "sek",
+    );
+    expect(batchGetCloudSandboxes).not.toHaveBeenCalled();
+    expect(ConversationService.getVSCodeUrl).not.toHaveBeenCalled();
+  });
+});
diff --git a/src/api/cloud/sandbox-service.api.ts b/src/api/cloud/sandbox-service.api.ts
new file mode 100644
index 0000000000..98bcd52b20
--- /dev/null
+++ b/src/api/cloud/sandbox-service.api.ts
@@ -0,0 +1,39 @@
+import { getActiveBackend } from "../backend-registry/active-store";
+import type { Backend } from "../backend-registry/types";
+import { callCloudProxy } from "./proxy";
+import type { V1SandboxInfo } from "./sandbox-service.types";
+
+function getActiveCloudBackend(): Backend {
+  const active = getActiveBackend().backend;
+  if (active.kind !== "cloud") {
+    throw new Error("Cloud sandboxes call requires a cloud backend.");
+  }
+  return active;
+}
+
+/**
+ * Batch-fetch cloud sandboxes by id. Mirrors OpenHands'
+ * `SandboxService.batchGetSandboxes` — routes through the bundled
+ * agent-server's cloud proxy and hits `GET /api/v1/sandboxes?id=...` on
+ * the SaaS, returning each `SandboxInfo` (or null if not found).
+ *
+ * The returned `SandboxInfo.exposed_urls` carry the SaaS-computed,
+ * publicly-reachable URLs for the sandbox's services (VSCODE,
+ * AGENT_SERVER, WORKER_*) — the GUI reads them directly instead of
+ * asking the runtime for `/api/vscode/url`, which only knows its
+ * internal localhost address.
+ */
+export async function batchGetCloudSandboxes(
+  ids: string[],
+): Promise<(V1SandboxInfo | null)[]> {
+  if (ids.length === 0) return [];
+  const backend = getActiveCloudBackend();
+  const params = new URLSearchParams();
+  for (const id of ids) params.append("id", id);
+  const data = await callCloudProxy<(V1SandboxInfo | null)[]>({
+    backend,
+    method: "GET",
+    path: `/api/v1/sandboxes?${params.toString()}`,
+  });
+  return data ?? [];
+}
diff --git a/src/api/cloud/sandbox-service.types.ts b/src/api/cloud/sandbox-service.types.ts
new file mode 100644
index 0000000000..a4848951bb
--- /dev/null
+++ b/src/api/cloud/sandbox-service.types.ts
@@ -0,0 +1,21 @@
+export type V1SandboxStatus =
+  | "STARTING"
+  | "RUNNING"
+  | "PAUSED"
+  | "ERROR"
+  | "MISSING";
+
+export interface V1ExposedUrl {
+  name: string;
+  url: string;
+}
+
+export interface V1SandboxInfo {
+  id: string;
+  created_by_user_id: string | null;
+  sandbox_spec_id: string;
+  status: V1SandboxStatus;
+  session_api_key: string | null;
+  exposed_urls: V1ExposedUrl[] | null;
+  created_at: string;
+}
diff --git a/src/api/conversation-service/agent-server-conversation-service.api.ts b/src/api/conversation-service/agent-server-conversation-service.api.ts
index d775bab365..9b75b82492 100644
--- a/src/api/conversation-service/agent-server-conversation-service.api.ts
+++ b/src/api/conversation-service/agent-server-conversation-service.api.ts
@@ -186,28 +186,13 @@ class AgentServerConversationService {
     conversationUrl: string | null | undefined,
     sessionApiKey?: string | null,
   ): Promise<GetVSCodeUrlResponse> {
-    const active = getActiveBackend().backend;
-
-    // Cloud mode: route through the cloud-proxy to the runtime sandbox.
-    // The runtime exposes a SaaS-style endpoint at `/api/vscode/url`
-    // that returns `{ url }`; we map it back to `{ vscode_url }` to
-    // match the local response shape.
-    if (active.kind === "cloud" && conversationUrl) {
-      const data = await callCloudProxy<{ url: string | null }>({
-        backend: active,
-        method: "GET",
-        hostOverride: buildHttpBaseUrl(conversationUrl),
-        path: "/api/vscode/url",
-        authMode: "session-api-key",
-        sessionApiKey,
-      });
-      return { vscode_url: data?.url ?? null };
-    }
-
+    // Local-only path. Cloud conversations read the VSCode URL straight
+    // from the SaaS-computed `sandbox.exposed_urls` (see
+    // `useUnifiedVSCodeUrl` + `useCloudSandbox`); the runtime's own
+    // `/api/vscode/url` only knows its internal `localhost:8001`, which
+    // the user's browser can't reach.
     const workspaceDir =
       await this.resolveConversationWorkingDir(conversationId);
-    // Local mode: the typescript-client targets the local agent-server
-    // directly via the conversationUrl override.
     const vscodeUrl = await createVSCodeClient({
       conversationUrl,
       sessionApiKey,
diff --git a/src/hooks/query/use-cloud-sandbox.ts b/src/hooks/query/use-cloud-sandbox.ts
new file mode 100644
index 0000000000..0841a2e2ab
--- /dev/null
+++ b/src/hooks/query/use-cloud-sandbox.ts
@@ -0,0 +1,20 @@
+import { useQuery } from "@tanstack/react-query";
+import { batchGetCloudSandboxes } from "#/api/cloud/sandbox-service.api";
+import { useActiveBackend } from "#/contexts/active-backend-context";
+
+export const useCloudSandbox = (sandboxId: string | null | undefined) => {
+  const active = useActiveBackend();
+  const isCloud = active.backend.kind === "cloud";
+
+  return useQuery({
+    queryKey: ["cloud", "sandbox", active.backend.id, active.orgId, sandboxId],
+    queryFn: async () => {
+      if (!sandboxId) return null;
+      const [sandbox] = await batchGetCloudSandboxes([sandboxId]);
+      return sandbox ?? null;
+    },
+    enabled: isCloud && !!sandboxId,
+    staleTime: 1000 * 60 * 5,
+    gcTime: 1000 * 60 * 15,
+  });
+};
diff --git a/src/hooks/query/use-unified-vscode-url.ts b/src/hooks/query/use-unified-vscode-url.ts
index a8298eec02..b84f1c0d68 100644
--- a/src/hooks/query/use-unified-vscode-url.ts
+++ b/src/hooks/query/use-unified-vscode-url.ts
@@ -7,27 +7,40 @@ import AgentServerConversationService from "#/api/conversation-service/agent-ser
 import { transformVSCodeUrl } from "#/utils/vscode-url-helper";
 import { useRuntimeIsReady } from "#/hooks/use-runtime-is-ready";
 import { useActiveConversation } from "#/hooks/query/use-active-conversation";
+import { useActiveBackend } from "#/contexts/active-backend-context";
+import { useCloudSandbox } from "#/hooks/query/use-cloud-sandbox";
 
 interface VSCodeUrlResult {
   url: string | null;
 }
 
+const VSCODE_EXPOSED_URL_NAME = "VSCODE";
+
 export const useUnifiedVSCodeUrl = () => {
   const { t } = useTranslation("openhands");
   const { conversationId } = useConversationId();
   const runtimeIsReady = useRuntimeIsReady({ allowAgentError: true });
   const { data: conversation } = useActiveConversation();
+  const active = useActiveBackend();
 
   const conversationUrl = conversation?.conversation_url ?? null;
   const sessionApiKey = conversation?.session_api_key ?? null;
+  const sandboxId = conversation?.sandbox_id ?? null;
+  const isCloud = active.backend.kind === "cloud";
 
-  const mainQuery = useQuery<VSCodeUrlResult>({
+  // Cloud mode: read VSCode URL from the SaaS-computed `exposed_urls` on
+  // the conversation's sandbox. The runtime's `/api/vscode/url` only
+  // knows its internal `localhost:8001`, so calling it returned a URL
+  // the user's browser couldn't reach.
+  const cloudSandboxQuery = useCloudSandbox(isCloud ? sandboxId : null);
+
+  const localQuery = useQuery<VSCodeUrlResult>({
     // Include conversation host + key in the cache key so different
-    // conversations don't share VSCode URL data, and so a cloud-→-local
-    // (or vice versa) swap re-fetches against the right host.
+    // conversations don't share VSCode URL data.
     queryKey: [
       "unified",
       "vscode_url",
+      "local",
       conversationId,
       conversationUrl,
       sessionApiKey,
@@ -35,9 +48,6 @@ export const useUnifiedVSCodeUrl = () => {
     queryFn: async () => {
       if (!conversationId) throw new Error("No conversation ID");
 
-      // Forward the conversation's owning host + session key so cloud
-      // conversations hit their cloud sandbox rather than falling back
-      // to the bundled local agent-server.
       const response = await AgentServerConversationService.getVSCodeUrl(
         conversationId,
         conversationUrl,
@@ -46,25 +56,69 @@ export const useUnifiedVSCodeUrl = () => {
 
       return { url: transformVSCodeUrl(response.vscode_url) };
     },
-    enabled: runtimeIsReady && !!conversationId,
+    enabled: !isCloud && runtimeIsReady && !!conversationId,
     refetchOnMount: true,
     retry: 3,
   });
 
+  let data: VSCodeUrlResult | undefined;
+  let isLoading: boolean;
+  let isError: boolean;
+  let isSuccess: boolean;
+  let status: typeof localQuery.status;
+  let error: unknown;
+  let refetch: () => Promise<{ data: VSCodeUrlResult | undefined }>;
+
+  if (isCloud) {
+    const sandbox = cloudSandboxQuery.data;
+    const exposedUrl =
+      sandbox?.exposed_urls?.find((u) => u.name === VSCODE_EXPOSED_URL_NAME)
+        ?.url ?? null;
+    data = cloudSandboxQuery.isSuccess
+      ? { url: transformVSCodeUrl(exposedUrl) }
+      : undefined;
+    isLoading = cloudSandboxQuery.isLoading;
+    isError = cloudSandboxQuery.isError;
+    isSuccess = cloudSandboxQuery.isSuccess;
+    status = cloudSandboxQuery.status;
+    error = cloudSandboxQuery.error;
+    refetch = async () => {
+      const result = await cloudSandboxQuery.refetch();
+      const refreshedUrl =
+        result.data?.exposed_urls?.find(
+          (u) => u.name === VSCODE_EXPOSED_URL_NAME,
+        )?.url ?? null;
+      return {
+        data: result.data
+          ? { url: transformVSCodeUrl(refreshedUrl) }
+          : undefined,
+      };
+    };
+  } else {
+    data = localQuery.data;
+    isLoading = localQuery.isLoading;
+    isError = localQuery.isError;
+    isSuccess = localQuery.isSuccess;
+    status = localQuery.status;
+    error = localQuery.error;
+    refetch = async () => {
+      const result = await localQuery.refetch();
+      return { data: result.data };
+    };
+  }
+
   // Derive the i18n'd "URL unavailable" message outside `queryFn` so the
   // queryKey doesn't have to include `t`.
-  const error =
-    mainQuery.data && !mainQuery.data.url
-      ? t(I18nKey.VSCODE$URL_NOT_AVAILABLE)
-      : null;
+  const errorMessage =
+    data && !data.url ? t(I18nKey.VSCODE$URL_NOT_AVAILABLE) : null;
 
   return {
-    data: mainQuery.data ? { ...mainQuery.data, error } : undefined,
-    error: mainQuery.error,
-    isLoading: mainQuery.isLoading,
-    isError: mainQuery.isError,
-    isSuccess: mainQuery.isSuccess,
-    status: mainQuery.status,
-    refetch: mainQuery.refetch,
+    data: data ? { ...data, error: errorMessage } : undefined,
+    error,
+    isLoading,
+    isError,
+    isSuccess,
+    status,
+    refetch,
   };
 };