TL

// Basic types
int ? = Int;
long ? = Long;
double ? = Double;
string ? = String;

// Vector
vector {t:Type} # [ t ] = Vector t;

// User type
user#d23c81a3 id:long access_hash:long first_name:string last_name:string username:string phone:string photo:UserProfilePhoto status:UserStatus = User;

// Message type
message#e470bcfd flags:# out:flags.1?true mentioned:flags.4?true media_unread:flags.5?true silent:flags.13?true post:flags.14?true from_scheduled:flags.18?true legacy:flags.19?true edit_hide:flags.21?true pinned:flags.24?true id:int from_id:flags.8?Peer peer_id:Peer fwd_from:flags.2?MessageFwdHeader via_bot_id:flags.11?long reply_to:flags.3?MessageReplyHeader date:int message:string media:flags.9?MessageMedia reply_markup:flags.6?ReplyMarkup entities:flags.7?Vector<MessageEntity> views:flags.10?int forwards:flags.10?int replies:flags.23?MessageReplies edit_date:flags.15?int post_author:flags.16?string grouped_id:flags.17?long reactions:flags.20?MessageReactions restriction_reason:flags.22?Vector<RestrictionReason> ttl_period:flags.25?int = Message;

// Function declaration
messages.sendMessage#d9d75a4 flags:# no_webpage:flags.1?true silent:flags.5?true background:flags.6?true clear_draft:flags.7?true noforwards:flags.14?true peer:InputPeer reply_to_msg_id:flags.0?int message:string random_id:long reply_markup:flags.2?ReplyMarkup entities:flags.3?Vector<MessageEntity> schedule_date:flags.10?int send_as:flags.13?InputPeer = Updates;