Use records that show each party’s genuine role, including the employment terms and the scope of services. A customer should not be asked to certify facts it cannot know.
Assign evidence to the party with knowledge
Build the package from the arrangement that actually exists. The U.S. employer can normally explain the offered position, salary, supervision, and duration.
A statement of work or client agreement may show the project, location, deliverables, and limits of the customer relationship. Where the applicant will be assigned to a customer, identify who retains employment authority and how the professional work is directed. Avoid a stack of generic letters that repeat a title but omit the activities that matter.
If a document contains a condition, such as a project award, access requirement, or customer approval, preserve that condition instead of rewriting it as certainty. Include credential evidence and citizenship evidence separately; neither proves the employment arrangement. For a foreign-language supporting record, check whether the selected process requires a complete certified translation.
A short explanatory note can help a reviewer navigate the records, but it should point back to the agreement, offer, or project document rather than make unsupported promises about the future. Keep a contact list for the people who can authenticate each record, particularly where a customer contract uses technical language. If a contract is revised, retain both versions and explain the change.
Accuracy about a limited project is more useful than a broad letter that the underlying commercial records cannot support.