diff --git a/src/interface.jl b/src/interface.jl
index 0110ff2..4b3e7cc 100644
--- a/src/interface.jl
+++ b/src/interface.jl
@@ -753,6 +753,7 @@ function conversation(a::T, userinput::Dict) where {T<:agent}
     addNewMessage(a, "user", userinput[:text])
 
     if isempty(a.plan[:currenttrajectory])
+
       a.plan[:currenttrajectory] = Dict{Symbol, Any}(
         # deepcopy the info to prevent modifying the info unintentionally during MCTS planning
         :customerinfo=> deepcopy(a.keywordinfo[:customerinfo]),
@@ -769,7 +770,10 @@ function conversation(a::T, userinput::Dict) where {T<:agent}
         :thoughtHistory=> OrderedDict{Symbol, Any}( 
           #[] :recap=>,
           :question=> userinput[:text],
-          )  
+          ),
+        :virtualCustomerChatHistory=> Vector{Dict{Symbol, Any}}(
+          [Dict(:name=> "user", :text=> userinput[:text])]
+          ),  
         )
     else
       _, a.plan[:currenttrajectory] = makeNewState(a.plan[:currenttrajectory], 
@@ -780,7 +784,7 @@ function conversation(a::T, userinput::Dict) where {T<:agent}
 
   while true
     bestNextState, besttrajectory = runMCTS(a, a.plan[:currenttrajectory], decisionMaker, 
-        evaluator, reflector, totalsample=2, maxDepth=2, maxiterations=1, explorationweight=1.0)
+        evaluator, reflector, totalsample=2, maxDepth=2, maxiterations=2, explorationweight=1.0)
     a.plan[:activeplan] = bestNextState
 
     latestActionKey, latestActionIndice = 
diff --git a/src/llmfunction.jl b/src/llmfunction.jl
index 98df02f..b176daa 100644
--- a/src/llmfunction.jl
+++ b/src/llmfunction.jl
@@ -3,7 +3,7 @@ module llmfunction
 export  virtualWineUserChatbox, jsoncorrection, winestock,
         virtualWineUserRecommendbox, userChatbox, userRecommendbox
 
-using HTTP, JSON3, URIs, Random
+using HTTP, JSON3, URIs, Random, PrettyPrinting
 using GeneralUtils
 using ..type, ..util
 
@@ -164,28 +164,119 @@ julia>
 
 # TODO
   - [] update docs 
+  - [x] write a prompt for virtual customer 
 
 # Signature
 """
-function virtualWineUserChatbox(a::T1, input::T2
+function virtualWineUserChatbox(a::T1, input::T2, virtualCustomerChatHistory
   )::Union{Tuple{String, Number, Number, Bool}, Tuple{String, Nothing, Number, Bool}} where {T1<:agent, T2<:AbstractString}
 
-  # put in model format
-  virtualWineCustomer = a.config[:externalservice][:virtualWineCustomer_1]
-  llminfo = virtualWineCustomer[:llminfo]
-  prompt = 
-  if llminfo[:name] == "llama3instruct"
-    formatLLMtext_llama3instruct("assistant", input)
-  else
-    error("llm model name is not defied yet $(@__LINE__)")
+  previouswines = 
+  """
+  You have the following wines previously:
+
+  """
+
+  systemmsg = 
+  """
+  You find yourself in a well-stocked wine store, engaged in a conversation with the store's knowledgeable sommelier. 
+  You're on a quest to find a bottle of wine that aligns with your specific preferences and requirements. 
+  
+  The ideal wine you're seeking should meet the following criteria:
+  1. It should fit within your budget.
+  2. It should be suitable for the occasion you're planning.
+  3. It should pair well with the food you intend to serve.
+  4. It should be of a particular type of wine you prefer.
+  5. It should possess certain characteristics, including:
+    - The level of sweetness.
+    - The intensity of its flavor.
+    - The amount of tannin it contains.
+    - Its acidity level.
+
+  Here's the criteria details:
+  {
+    "budget": 50,
+    "occasion": "graduation ceremony",
+    "food pairing": "Thai food",
+    "type of wine": "red",
+    "wine sweetness level": "dry",
+    "wine intensity level": "full-bodied",
+    "wine tannin level": "low",
+    "wine acidity level": "medium", 
+  }
+
+  You should only respond with "text", "select", "reward", "isterminal" steps.
+  "text" is your conversation.
+  "select" is an integer. Choose an option when presented with choices, or leave it null if none of the options satisfy you or if no choices are available.
+  "reward" is an integer, it can be three number:
+    1) 1 if you find the right wine.
+    2) 0 if you don’t find the ideal wine.
+    3) -1 if you’re dissatisfied with the sommelier’s response.
+  "isterminal" can be false if you still want to talk with the sommelier, true otherwise.
+
+  You should only respond in JSON format as describe below:
+  {
+    "text": "your conversation",
+    "select": null,
+    "reward": 0,
+    "isterminal": false
+  }
+
+  Here are some examples:
+  {
+    "text": "My budget is 30 USD.",
+    "select": null,
+    "reward": 0,
+    "isterminal": false
+  }
+  {
+    "text": "I like the 2nd option.",
+    "select": 2,
+    "reward": 1,
+    "isterminal": true
+  }
+
+  Let's begin!
+  """
+
+  pushfirst!(virtualCustomerChatHistory, Dict(:name=> "system", :text=> systemmsg))
+  
+  # replace the :user key in chathistory to allow the virtual wine customer AI roleplay
+  chathistory::Vector{Dict{Symbol, Any}} = Vector{Dict{Symbol, Any}}()
+  for i in virtualCustomerChatHistory
+    newdict = Dict()
+    newdict[:name] =
+    if i[:name] == "user"
+      "you"
+    elseif i[:name] == "assistant"
+      "sommelier"
+    else
+      i[:name]
+    end
+
+    newdict[:text] = i[:text]
+    push!(chathistory, newdict)
   end
 
+  push!(chathistory, Dict(:name=> "assistant", :text=> input))
+
+  # put in model format
+  prompt = formatLLMtext(chathistory, "llama3instruct")
+  prompt *=
+    """
+    <|start_header_id|>you<|end_header_id|>
+    {"text"
+    """
+
+  pprint(prompt)
+  externalService = a.config[:externalservice][:text2textinstruct]
+
   # send formatted input to user using GeneralUtils.sendReceiveMqttMsg
   msgMeta = GeneralUtils.generate_msgMeta(
-    virtualWineCustomer[:mqtttopic],
+    externalService[:mqtttopic],
     senderName= "virtualWineUserChatbox",
     senderId= a.id,
-    receiverName= "virtualWineCustomer",
+    receiverName= "text2textinstruct",
     mqttBroker= a.config[:mqttServerInfo][:broker],
     mqttBrokerPort= a.config[:mqttServerInfo][:port],
     msgId = "dummyid" #CHANGE remove after testing finished
@@ -201,10 +292,33 @@ function virtualWineUserChatbox(a::T1, input::T2
   attempt = 0
   for attempt in 1:5
     try
-      result = GeneralUtils.sendReceiveMqttMsg(outgoingMsg; timeout=120)
-      response = result[:response]
+      response = GeneralUtils.sendReceiveMqttMsg(outgoingMsg; timeout=120)
+      _responseJsonStr = response[:response][:text]
+      expectedJsonExample =
+      """
+      Here is an expected JSON format:
+      {
+        "text": "...",
+        "select": "...",
+        "reward": "...",
+        "isterminal": "..."
+      }
+      """
+      responseJsonStr = jsoncorrection(a, _responseJsonStr, expectedJsonExample)
+      responseDict = copy(JSON3.read(responseJsonStr)) 
 
-      return (response[:text], response[:select], response[:reward], response[:isterminal])
+      text = responseDict[:text]
+      select = responseDict[:select] == "null" ? nothing : responseDict[:select]
+      reward = responseDict[:reward]
+      isterminal = responseDict[:isterminal]
+
+      if text != "" && select != "" && reward != "" && isterminal != ""
+        # pass test
+      else
+        error("virtual customer not answer correctly")
+      end
+      
+      return (text, select, reward, isterminal)
     catch e
       io = IOBuffer()
       showerror(io, e)
@@ -218,6 +332,57 @@ function virtualWineUserChatbox(a::T1, input::T2
   error("virtualWineUserChatbox failed to get a response")
 end
 
+# function virtualWineUserChatbox(a::T1, input::T2
+#   )::Union{Tuple{String, Number, Number, Bool}, Tuple{String, Nothing, Number, Bool}} where {T1<:agent, T2<:AbstractString}
+
+#   # put in model format
+#   virtualWineCustomer = a.config[:externalservice][:virtualWineCustomer_1]
+#   llminfo = virtualWineCustomer[:llminfo]
+#   prompt = 
+#   if llminfo[:name] == "llama3instruct"
+#     formatLLMtext_llama3instruct("assistant", input)
+#   else
+#     error("llm model name is not defied yet $(@__LINE__)")
+#   end
+
+#   # send formatted input to user using GeneralUtils.sendReceiveMqttMsg
+#   msgMeta = GeneralUtils.generate_msgMeta(
+#     virtualWineCustomer[:mqtttopic],
+#     senderName= "virtualWineUserChatbox",
+#     senderId= a.id,
+#     receiverName= "virtualWineCustomer",
+#     mqttBroker= a.config[:mqttServerInfo][:broker],
+#     mqttBrokerPort= a.config[:mqttServerInfo][:port],
+#     msgId = "dummyid" #CHANGE remove after testing finished
+#   )
+
+#   outgoingMsg = Dict(
+#     :msgMeta=> msgMeta,
+#     :payload=> Dict(
+#       :text=> prompt,
+#     )
+#   )
+
+#   attempt = 0
+#   for attempt in 1:5
+#     try
+#       result = GeneralUtils.sendReceiveMqttMsg(outgoingMsg; timeout=120)
+#       response = result[:response]
+
+#       return (response[:text], response[:select], response[:reward], response[:isterminal])
+#     catch e
+#       io = IOBuffer()
+#       showerror(io, e)
+#       errorMsg = String(take!(io))
+#       st = sprint((io, v) -> show(io, "text/plain", v), stacktrace(catch_backtrace()))
+#       println("")
+#       @warn "Error occurred: $errorMsg\n$st"
+#       println("")
+#     end
+#   end
+#   error("virtualWineUserChatbox failed to get a response")
+# end
+
 
 """ Search wine in stock.
 
@@ -239,7 +404,7 @@ julia> result = winestock(agent, input)
 
 # TODO
   [] update docs
-  [PENDING] implement the function
+  [WORKING] implement the function
 
 # Signature
 """
@@ -302,8 +467,8 @@ function jsoncorrection(a::T1, input::T2,
       _prompt =
       """
       Your goal are:
-      1) Use the info why the given JSON string failed to load and provide a corrected version that can be loaded by Python's json.load function.
-      2) The user need Corrected JSON string only. Do not provide any other info.
+      1) Use the expected JSON format as a guideline to check why the given JSON string failed to load and provide a corrected version that can be loaded by Python's json.load function.
+      2) Provide Corrected JSON string only. Do not provide any other info.
 
       $correctJsonExample
 
diff --git a/src/mcts.jl b/src/mcts.jl
index 5632351..536fc33 100644
--- a/src/mcts.jl
+++ b/src/mcts.jl
@@ -146,7 +146,6 @@ function expand(a::T1, node::MCTSNode, decisionMaker::Function,
       pprintln(thoughtDict)
       newNodeKey, newstate = MCTStransition(a, node.state, thoughtDict)
       
-
       stateevaluation, progressvalue = evaluator(a, newstate)
 
       if newstate[:reward] < 0
@@ -302,7 +301,9 @@ function MCTStransition(a::T1, state::T2, thoughtDict::T2
   # map action and input() to llm function
   response, select, reward, isterminal =
   if actionname == "chatbox"
-    virtualWineUserChatbox(a, actioninput)  # virtual customer
+    # deepcopy(state[:virtualCustomerChatHistory]) because I want to keep it clean
+    # so that other simulation start from this same node is not contaminated with actioninput
+    virtualWineUserChatbox(a, actioninput, deepcopy(state[:virtualCustomerChatHistory]))  # virtual customer
   elseif actionname == "winestock"
     winestock(a, actioninput)
   elseif actionname == "recommendbox"  
@@ -311,7 +312,13 @@ function MCTStransition(a::T1, state::T2, thoughtDict::T2
     error("undefined LLM function. Requesting $actionname")
   end
 
-  return makeNewState(state, thoughtDict, response, select, reward, isterminal)
+  newNodeKey, newstate = makeNewState(state, thoughtDict, response, select, reward, isterminal)
+  if actionname == "chatbox"
+    push!(newstate[:virtualCustomerChatHistory], Dict(:name=>"assistant", :text=> actioninput) )
+    push!(newstate[:virtualCustomerChatHistory], Dict(:name=>"user", :text=> response))
+  end
+
+  return (newNodeKey, newstate)
 end
 
 
@@ -386,7 +393,7 @@ julia>
 
 # TODO
   - [] update docstring
-  - [TESTING] implement the function
+  - [x] implement the function
 
 # Signature
 """
@@ -520,7 +527,7 @@ julia>
 
 # TODO
   - [] update docs
-  - [TESTING] implement the function
+  - [x] implement the function
 
 # Signature
 """
@@ -573,7 +580,7 @@ julia>
 
 # TODO
   - [] update docs
-  - [TESTING] implement the function
+  - [x] implement the function
 
 # Signature
 """
@@ -675,7 +682,7 @@ function runMCTS(
       leafNode = selectChildNode(node)
       simTrajectoryReward, terminalstate = simulate(a, leafNode, decisionMaker, evaluator, 
                                     reflector; maxDepth=maxDepth, totalsample=totalsample)
-      if terminalstate !== nothing
+      if terminalstate !== nothing  #XXX not sure why I need this 
         terminalstate[:totalTrajectoryReward] = simTrajectoryReward
       end
 
diff --git a/src/util.jl b/src/util.jl
index 80138c8..fa28a7e 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -201,13 +201,13 @@ function formatLLMtext_llama3instruct(name::T, text::T) where {T<:AbstractString
     <|begin_of_text|>
     <|start_header_id|>$name<|end_header_id|>
     $text
-    <|eot_id|>\n
+    <|eot_id|>
     """
   else
     """
     <|start_header_id|>$name<|end_header_id|>
     $text
-    <|eot_id|>\n
+    <|eot_id|>
     """
   end
 
@@ -286,7 +286,7 @@ end
   TODO\n
   -----
     [] update docstring
-    [TESTING] implement the function
+    [PENDING] implement the function
 
   Signature\n
   -----
diff --git a/test/runtest.jl b/test/runtest.jl
index dd617e9..3e4fc6a 100644
--- a/test/runtest.jl
+++ b/test/runtest.jl
@@ -51,8 +51,6 @@ tools=Dict( # update input format
   )
 
   a = YiemAgent.sommelier(
-    receiveUserMsgChannel,
-    receiveInternalMsgChannel,
     agentConfig, 
     name="assistant",
     id="testingSessionID",  # agent instance id
@@ -68,7 +66,7 @@ response = YiemAgent.conversation(a, Dict(:text=> "Hello, I would like a get a b
                                 ) )
 println("---> YiemAgent: ", response)
 
-response = YiemAgent.conversation(a, Dict(:text=> "I'm having a graduation party this evening",
+response = YiemAgent.conversation(a, Dict(:text=> "I'm having a graduation party this evening. I'll pay at most 30 bucks.",
                                           :select=> nothing,
                                           :reward=> 0,
                                           :isterminal=> false,