Type Alias: MessageTextInput

MessageTextInput = string | { attachment_id?: string; recipient_id?: string; text?: string; voice_url?: string; }

What sendMessage takes as the message. A plain string is the text. The object form can also carry a private recipient and a file (attachment_id, or the deprecated voice_url) — see Emby.sendMessage for where each comes from. With a file the text is optional and becomes the caption.