Readable stream(s) to be sent as attachments. Can be any file, image, voiceclip...
a plain-text content of the outgoing message
Additional information when sending a message with user mentions. This property contains sorted "name & id" pairs.
message ID to which this new message would respond
ID of the desired sticker
Message can only be a regular message (
bodyfield set) and optionally one of asticker,attachmentorurl