2.2.2.4 login_hint OR username

 GET /authorize?response_type={response_type}&client_id={client_id}&state={state}&resource={resource}&login_hint={login_hint}&redirect_uri={redirect_uri} HTTP/1.1

OPTIONAL

When an OAuth 2.0 client requests authorization from an AD FS server (as specified in [RFC6749] sections 4.1 and 4.2), it MAY use the login_hint query parameter. This query parameter provides a hint to the AD FS server about the login identifier the end user might use to log in.

Note: login_hint and username are aliases that signify the same query parameter. The OAuth 2.0 client can use either of these query parameters to provide a hint to the AD FS server about the login identifier the end user might use to log in.

The following is an example of the login_hint query parameter as it is being used (which could be added to the example in section 4.1).

 &login_hint=janedow@contoso.com

The format for the login_hint query parameter is as follows.

 String = *(%x20-7E)
 login_hint OR username = String