First questions for an integration from a HRIS to SaaS provider

First piece of guidance is to make sure that the employee master data client provided / will provide to provider to build the payrolls was sourced from the HRIS or if not then the HRIS matches or will be updated to match the data provided to the provider. This is especially important for paycodes. As if the paycodes that were provided to build the payroll do not match the paycodes in HRIS then the integration will fail.