This page is just a reference of all the known Steam APIs, I do not know how they work. Please do not email me with questions.
UNDOCUMENTEDGetWGToken
https://api.steampowered.com/IMobileAuthService/GetWGToken/v1/
UNDOCUMENTEDPOSTMigrateMobileSession
https://api.steampowered.com/IMobileAuthService/MigrateMobileSession/v1/
NameValueTypeRequiredDescription
click to setstring Yes Access key
fixed64 NoSteam ID of the user to migrate
string NoWG Token to migrate
bytes NoSignature over the wg token using the user's 2FA token
CMobileAuth_MigrateMobileSession_Request_DeviceDetails NoUser-supplied description of the authenticating device
↳ string No
↳ uint32 No
↳ int32 No
↳ uint32 No