The Magic Link `token` from the `?token=` query parameter in the URL. The redirect URL will look like `https://example.com/authenticate?stytch_token_type=magic_links&token=rM_kw42CWBhsHLF62V75jELMbvJ87njMe3tFVj7Qupu7` In the redirect URL, the `stytch_token_type` will be `magic_link`. See [here](https://stytch.com/docs/workspace-management/redirect-urls) for more detail.

The `session_token` associated with a User's existing Session.

Set the session lifetime to be this many minutes from now. This will start a new session if one doesn't already exist, returning both an opaque `session_token` and `session_jwt` for this session. Remember that the `session_jwt` will have a fixed lifetime of five minutes regardless of the underlying session duration, and will need to be refreshed over time. This value must be a minimum of 5 and a maximum of 527040 minutes (366 days). If a `session_token` or `session_jwt` is provided then a successful authentication will continue to extend the session this many minutes. If the `session_duration_minutes` parameter is not specified, a Stytch session will not be created.

The `session_jwt` associated with a User's existing Session.

Add a custom claims map to the Session being authenticated. Claims are only created if a Session is initialized by providing a value in `session_duration_minutes`. Claims will be included on the Session object and in the JWT. To update a key in an existing Session, supply a new value. To delete a key, supply a null value. Custom claims made with reserved claims ("iss", "sub", "aud", "exp", "nbf", "iat", "jti") will be ignored. Total custom claims size cannot exceed four kilobytes.

A base64url encoded one time secret used to validate that the request starts and ends on the same device.

If the `telemetry_id` is passed, as part of this request, Stytch will call the [Fingerprint Lookup API](https://stytch.com/docs/fraud/api/fingerprint-lookup) and store the associated fingerprints and IPGEO information for the User. Your workspace must be enabled for Device Fingerprinting to use this feature.