diff --git a/test/e2e-scenario/support-tests/onboard-create-plan-guard-parity.test.ts b/test/e2e-scenario/support-tests/onboard-create-plan-guard-parity.test.ts
new file mode 100644
index 00000000000..f367524da55
--- /dev/null
+++ b/test/e2e-scenario/support-tests/onboard-create-plan-guard-parity.test.ts
@@ -0,0 +1,90 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+import { describe, expect, it, vi } from "vitest";
+
+import {
+  type OnboardEntryOptionsDeps,
+  resolveOnboardEntryOptions,
+} from "../../../dist/lib/onboard/entry-options";
+
+class ExitError extends Error {
+  constructor(readonly code: number) {
+    super(`exit ${code}`);
+  }
+}
+
+function createDeps(overrides: Partial<OnboardEntryOptionsDeps> = {}): OnboardEntryOptionsDeps {
+  return {
+    isNonInteractive: vi.fn(() => false),
+    validateName: vi.fn((name: string) => name.trim().toLowerCase()),
+    reservedSandboxNames: new Set(),
+    cliDisplayName: vi.fn(() => "NemoClaw"),
+    getNameValidationGuidance: vi.fn(() => ["Use lowercase letters, numbers, and hyphens."]),
+    error: vi.fn(),
+    exitProcess: vi.fn((code: number) => {
+      throw new ExitError(code);
+    }) as (code: number) => never,
+    ...overrides,
+  };
+}
+
+function expectExitOne(run: () => unknown): void {
+  let thrown: unknown;
+  try {
+    run();
+  } catch (error) {
+    thrown = error;
+  }
+  expect(thrown).toBeInstanceOf(ExitError);
+  expect(thrown).toMatchObject({ code: 1 });
+}
+
+describe("Package D onboard create-plan guard parity", () => {
+  it("preserves the legacy --from missing-name guard when prompts are unavailable", () => {
+    const deps = createDeps();
+
+    expectExitOne(() =>
+      resolveOnboardEntryOptions(
+        {
+          opts: { fromDockerfile: "Dockerfile.custom" },
+          env: {},
+          stdinIsTty: false,
+          stdoutIsTty: true,
+        },
+        deps,
+      ),
+    );
+    expect(deps.error).toHaveBeenCalledWith(
+      "  --from <Dockerfile> requires --name <sandbox> (or NEMOCLAW_SANDBOX_NAME) when running without a TTY or with --non-interactive.",
+    );
+    expect(deps.error).toHaveBeenCalledWith(
+      "  A sandbox name cannot be prompted for in this context.",
+    );
+  });
+
+  it("preserves the legacy --from + NEMOCLAW_SANDBOX_NAME validation path", () => {
+    const deps = createDeps({
+      validateName: vi.fn(() => {
+        throw new Error("Invalid sandbox name");
+      }),
+    });
+
+    expectExitOne(() =>
+      resolveOnboardEntryOptions(
+        {
+          opts: { fromDockerfile: "Dockerfile.custom" },
+          env: { NEMOCLAW_SANDBOX_NAME: "bad name" },
+          stdinIsTty: false,
+          stdoutIsTty: true,
+        },
+        deps,
+      ),
+    );
+    expect(deps.validateName).toHaveBeenCalledWith("bad name", "sandbox name");
+    expect(deps.error).toHaveBeenCalledWith("  Invalid sandbox name");
+    expect(deps.error).not.toHaveBeenCalledWith(
+      "  --from <Dockerfile> requires --name <sandbox> (or NEMOCLAW_SANDBOX_NAME) when running without a TTY or with --non-interactive.",
+    );
+  });
+});