This bot does nothing except for: accept your trade request, click ready when you do, and accept the trade when you do.

ReallySimpleUserHandler.cs

using SteamKit2;
using System.Collections.Generic;
using SteamTrade;

namespace SteamBot
{
    public class ReallySimpleUserHandler : UserHandler
    {
        public SimpleUserHandler (Bot bot, SteamID sid) : base(bot, sid) {}

        public override bool OnFriendAdd () 
        {
            return true;
        }
        
        public override void OnFriendRemove () {}
        
        public override void OnMessage (string message, EChatEntryType type) 
        {
            Bot.SteamFriends.SendChatMessage(OtherSID, type, Bot.ChatResponse);
        }

        public override bool OnTradeRequest() 
        {
            return true;
        }
        
        public override void OnTradeError (string error) 
        {
            Bot.SteamFriends.SendChatMessage (OtherSID, 
                                              EChatEntryType.ChatMsg,
                                              "Oh, there was an error: " + error + "."
                                              );
            Bot.log.Warn (error);
        }
        
        public override void OnTradeTimeout () 
        {
            Bot.SteamFriends.SendChatMessage (OtherSID, EChatEntryType.ChatMsg,
                                              "Sorry, but you were AFK and the trade was canceled.");
            Bot.log.Info ("User was kicked because he was AFK.");
        }
        
        public override void OnTradeInit() 
        {
            Trade.SendMessage ("Success. Please put up your items.");
        }
        
        public override void OnTradeAddItem (Schema.Item schemaItem, Inventory.Item inventoryItem) {}
        
        public override void OnTradeRemoveItem (Schema.Item schemaItem, Inventory.Item inventoryItem) {}
        
        public override void OnTradeMessage (string message) {}
        
        public override void OnTradeReady (bool ready) 
        {
            if (!ready)
            {
                Trade.SetReady (false);
            }
            else
            {
                Trade.SetReady (true);
            }
        }
        
        public override void OnTradeAccept() 
        {
            bool success = Trade.AcceptTrade();

            if (success)
            {
                Log.Success ("Trade was Successful!");
            }
            else
            {
                Log.Warn ("Trade might have failed.");
            }
            
            OnTradeClose ();
        }
    }
 
}

This isn't working anymore either 😢