Campus should only request enough to make informed decisions about accommodations. In Canada, college students and the Human Rights Commission are fighting for the right to provide documentation without specific diagnoses.
Most colleges have a person or full office that makes arrangements for disability accommodations. They use different names, like Disabled Student Services, Disability Resource Center or Accessibility Center, among others. Can't find it? Try using Google to search your college name and the term "disability services."
To get services and assistance from Disability Services (DS), you usually have to register with the office. They collect information about you, your disability and accommodations, and are required by law to keep that confidential, unless you give them permission to share it.
That information they collect is the "documentation" (finally!)
Because not all disabilities are easy to see or understand, documentation explains your disability and helps you and DS figure out what accommodations or services you might need.
Documentation of your disability also helps protect your rights under disability laws. If you've provided documentation of what you need, the college needs to provide services and accommodations.
There are three kinds of documentation: