// __tests__/api.contract.test.ts
test("POST /resource returns correct error shape on validation failure", async () => {
  const response = await fetch("/resource", {
    method: "POST",
    body: JSON.stringify({ field: "invalid" }),
  });

  const error = await response.json();

  expect(error).toMatchObject({
    success: false,
    error: "VALIDATION_ERROR",
    details: {
      validationErrors: expect.any(Array),
    },
  });
  expect(error).not.toHaveProperty("stack"); // 👈 NO LEAKS
});

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