Optional
completedA list of the stages the client has completed successfully
Optional
flowsA list of the login flows supported by the server for this API.
Optional
paramsContains any information that the client will need to know in order to use a given type of authentication. For each login type presented, that type may be present as a key in this dictionary. For example, the public part of an OAuth client ID could be given here.
Optional
sessionThis is a session identifier that the client must pass back to the home server, if one is provided, in subsequent attempts to authenticate in the same API call.
Data returned in the body of a 401 response from a UIA endpoint.
See
https://spec.matrix.org/v1.6/client-server-api/#user-interactive-api-in-the-rest-api