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VB.NET

Streaming AI with Manual AI Tool Function Calling

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Demonstrates how to get AI responses in streaming mode, including manual tool function calls.

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

' Create the following JSON to define tool functions available for the AI to use.
' Note: You'll use the following JSON format regardless of the AI provider, whether
' it be ChatGPT, Gemini, Claude, Grok, etc.  Chilkat automatically converts to the required
' format needed for a given AI provider.

' In this example, the application is providing a single function the AI may choose to call.

' {
'   "tools": [
'     {
'       "name": "get_horoscope",
'       "description": "Get today's horoscope for an astrological sign.",
'       "parameters": {
'         "properties": {
'           "sign": {
'             "type": "string",
'             "description": "An astrological sign like Taurus or Aquarius"
'           }
'         }
'       }
'     }
'   ]
' }

Dim jsonTools As New Chilkat.JsonObject

Dim toolIdx As Integer = 0

jsonTools.I = toolIdx
jsonTools.UpdateString("tools[i].name","get_horoscope")
jsonTools.UpdateString("tools[i].description","Get today's horoscope for an astrological sign.")
jsonTools.UpdateString("tools[i].parameters.properties.sign.type","string")
jsonTools.UpdateString("tools[i].parameters.properties.sign.description","An astrological sign like Taurus or Aquarius")
' More tools can be added as desired..

jsonTools.EmitCompact = False
Debug.WriteLine(jsonTools.Emit())

Dim ai As New Chilkat.Ai

' Register the tools that will be made available to the AI.
ai.RegisterManualTools(jsonTools)

' The provider can be "openai", "google", "claude", "grok", "mistral", "custom", etc.
ai.Provider = "openai"
' Use your provider's API key.
ai.ApiKey = "MY_API_KEY"
' Choose a model.
ai.Model = "gpt-5-mini"

' Tool function calling must always occur within a conversation.
Dim conversation_name As String = "convo_astrology"
Dim sysMessage As String = "You are a helpful astrologer"
Dim devMessage As String = "Respond only with markdown."
ai.NewConvo(conversation_name,sysMessage,devMessage)

' Provide inputs
ai.InputAddText("What is my horoscope? I am an Aquarius.")

' Get the response in streaming mode.
ai.Streaming = True

' In streaming mode, if we receive an AI event that is a request for tool use,
' we'll need to make the call to the JavaScript and then continue with a followup Ask,
' until the final response is received.

Dim sbEventName As New Chilkat.StringBuilder
Dim sbDelta As New Chilkat.StringBuilder
Dim sbFullResponse As New Chilkat.StringBuilder

' When PollAi returns with an event, it's highly unlikely the
' call to NextAiEvent does not immediately return.  Setting a max
' timeout is just a precaution..
Dim maxWaitMs As Integer = 5000

Dim jsonFn As New Chilkat.JsonObject

Dim finished As Boolean = False
Dim numAsks As Integer = 0
' Set a max # of followup Asks to prevent any unexpected infinite looping.
While Not finished And (numAsks < 10)

    ' Send the request to the AI model.
    success = ai.Ask("text")
    If (success = False) Then
        Debug.WriteLine(ai.LastErrorText)
        Exit Sub
    End If


    Dim madeFunctionCalls As Boolean = False
    Dim streamingDone As Boolean = False

    While Not streamingDone
        Dim result As Integer = ai.PollAi(False)
        If (result < 0) Then
            Debug.WriteLine(ai.LastErrorText)
            Debug.WriteLine("Failed.")
            Exit Sub
        End If

        If (result > 0) Then
            ' We have an event..
            success = ai.NextAiEvent(maxWaitMs,sbEventName,sbDelta)
            If (success = False) Then
                Debug.WriteLine(ai.LastErrorText)
                Exit Sub
            End If


            ' Is this an event where the AI is requesting a function call?
            If (sbEventName.ContentsEqual("function_call",True)) Then
                jsonFn.LoadSb(sbDelta)

                ' Note: Chilkat will convert responses from all AI providers to this format:

                ' {
                '   "function_call": [
                '     {
                '       "name": "get_horoscope",
                '       "call_id": "call_RYmeysYQFocFc7Z2ofkv61dW",
                '       "arguments": "{\"sign\":\"Aquarius\"}",
                '       "args": {
                '         "sign": "Aquarius"
                '       }
                '     }
                '   ]
                ' }

                Dim numFnCalls As Integer = jsonFn.SizeOfArray("function_call")
                Dim fn_idx As Integer = 0
                While (fn_idx < numFnCalls)
                    jsonFn.I = fn_idx

                    Dim sbFnName As New Chilkat.StringBuilder
                    jsonFn.StringOfSb("function_call[i].name",sbFnName)
                    Dim callId As String = jsonFn.StringOf("function_call[i].call_id")

                    If (sbFnName.ContentsEqual("get_horoscope",True) = True) Then

                        ' The get_horoscope function (as defined above) has one argument named "sign".
                        Dim zodiac_sign As String = jsonFn.StringOf("function_call[i].args.sign")
                        Debug.WriteLine("zodiac_sign = " & zodiac_sign)

                        ' Insert application code here to call your app's get_horoscope function, passing the zodiac_sign to it..

                        ' For this example, we'll pretend the app's get_horoscope function returned the following:
                        Dim applicationFnCallResult As String = "Aquarius: Next Tuesday you will befriend a baby otter."

                        ' Provide the tool call result as an input for the followup Ask.
                        ai.InputAddFnResult(callId,applicationFnCallResult)

                        madeFunctionCalls = True
                    End If

                    ' Your application would add code to check for and handle each possible function call.


                    fn_idx = fn_idx + 1
                End While


            Else
                If (Not sbEventName.ContentsEqual("empty",True)) Then
                    sbFullResponse.AppendSb(sbDelta)

                    If (sbEventName.ContentsEqual("null_terminator",True)) Then
                        streamingDone = True
                    End If

                End If

            End If


        Else
            ' No event arrived, so wait a short time rather than spin in a loop..
            ai.SleepMs(100)
        End If


    End While

    If (Not madeFunctionCalls) Then
        finished = True
    End If


    numAsks = numAsks + 1
End While

Debug.WriteLine("Full Response:")
Debug.WriteLine(sbFullResponse.GetAsString())