All Federal and state offices should assume a disabled person needs accommodations from the first contact. They should be asked what accommodations they need at the first contact, which may be via a web page on a mobile phone. Many disabled people do not use email because they forget or it's too hard to read. Webpages are a problem for people with a learning disability.
And keep the number of steps to apply for benefits or other services to a minimum. I'm the parent of a disabled person and I have trouble following all of the instructions from Social Security. And never assume the disabled person will have someone there whenever they are interacting with a Federal agency. My disabled child is an adult and is trying to be independent. But it's almost impossible for them to understand the instructions in written or online communications from Federal agencies.