Know who owns normal work and exceptions
Ask who handles onboarding, payroll changes, benefits questions, employee records and manager requests. Then ask what happens when the usual process fails. A useful agreement names the service roles, backup coverage, escalation contacts and work that requires an additional fee.
Expect evidence, not only availability
Regular reporting should show open items, completed tasks, response performance, recurring errors and upcoming decisions. Schedule service reviews around the problems the provider was hired to solve. If the relationship relies on informal promises rather than visible work, it will be difficult to manage.
For related guidance, read HR outsourcing vendor checklist and compare HR outsourcing providers.