Working for the federal government does not necessarily allow you to see patients via telepsychiatry, wherever you are. While there are no absolute contraindications to patients being assessed or treated using telemental health, you have to check with your supervisor — and any applicable administrative rules and trainings — for these rules.
Ask your supervisor about federal telework agreements, contingency plans for persons who appear in-person or who are unable to connect by video, and whether support staff are available to guide your patient in case of an outage.
Furthermore, telemedicine requires you to know which state a patient is located. You would need to follow that state's licensing laws and regulations. Usually, this means you must have a license to practice in that patient's state, have malpractice cover your practice in that state. Some states allow for a single state license to cover multiple states — the Interstate Licensure Compact, for instance — but not all states participate in this.
Resources, such as the American Medical Association Telehealth quick guide, can help you determine which laws apply.