Employment Offer Letter Instructions. An effective offer letter sets forth the material terms of an employee's employment and makes clear that no other "unwritten" terms are part of the agreement.Offer letters must be prepared to preserve at-will employment status unless the employer consciously decides otherwise. See Preserving At-Will Status. In the formal offer letter, provide comprehensive details about the position, compensation, benefits, and other pertinent terms. Job Offer Letters – An employer must be careful about the terms that are used in job offer letters that are submitted to applicants. This legal template is a concise employment contract designed for non-executive roles in the state of Michigan.