How to make ToolCalls from a GroupChat Orchestration

[DD2XAlpha]

I am developing a multi-agentic solution, the problem is that on C# I don't see clear documentarion on how to do this. I have made my ChatCompletionAgents with toolcalls, individually they do work properly, but on the ChatGroup they don't.

I cannot share code due to privacy on it.

But my ChatCompletionAgents are something like this:

ChatCompletionAgent agent = new(){
 Instructions = instruction
 Name=name
 Kernel=_MyKernel
 Arguments = new KernelArguments(new AzureOpenAIPromptExecutionSettings(){
 FunctionChoiceBehaviour= FunctionChoiceBehaviour.Auto(),
 ToolCallBehaviour= ToolCallBehaviour.AutoInvokeFunctions
}

}

And my Orchestration is as how it is seen in this sample:

https://github.com/microsoft/semantic-kernel/blob/main/dotnet/samples/GettingStartedWithAgents/Orchestration/Step03_GroupChat.cs

[KeepALifeUS]

This is a common issue with group chats and tool execution. Here are some approaches:

1. Dedicated Tool Agent

Instead of having all agents invoke tools, designate one agent as the "tool executor":

// Analyzer agent - no tools, just analysis
var analyzerAgent = new ChatCompletionAgent {
    Name = "Analyzer",
    Instructions = "Analyze and request tool calls from ToolExecutor"
};

// Tool executor - has all tools
var toolExecutorAgent = new ChatCompletionAgent {
    Name = "ToolExecutor",
    Instructions = "Execute tools when requested",
    Kernel = kernelWithTools,
    Arguments = new KernelArguments(settings)
};

2. State-Based Tool Routing

Track tool requests in shared state:

var state = new Dictionary<string, object> {
    ["pending_tool_calls"] = new List<ToolCall>(),
    ["tool_results"] = new Dictionary<string, object>()
};

// When agent requests tool
if (message.Contains("TOOL_REQUEST:")) {
    state["pending_tool_calls"].Add(ParseToolRequest(message));
    // Route to tool executor
}

3. Check Agent Kernel Configuration

Ensure each agent in the group has its own properly configured Kernel:

foreach (var agent in groupChat.Agents) {
    if (agent is ChatCompletionAgent cca) {
        // Verify kernel has plugins
        var plugins = cca.Kernel.Plugins;
        // Verify settings allow auto-invoke
    }
}

Root Cause

In group chats, the orchestration layer may intercept messages before tool calls are processed. The solution is often to make tool execution explicit rather than relying on auto-invocation.

Could you share how your ChatGroup is configured?