sub agents instead of agent as tools

[Mohanr1122]

Description

Currently, when building hierarchical agent patterns in the .NET implementation of the Microsoft Agent Framework, adding a child/sub-agent to a parent agent requires converting the sub-agent into an AIFunction via .AsAIFunction() and injecting it into the parent's Tools collection.

Proposed Solution

Provide a native way to attach child agents to a parent agent directly, separate from the Tools collection. For example:

var subAgent = new ChatClientAgent(chatClient, instructions: "Deep analyzer...", name: "Analyzer");

var parentAgent = new ChatClientAgent(
    chatClient,
    instructions: "You are the primary coordinator.",
    name: "Coordinator",
    subAgents: [ subAgent ] // <-- Native architectural support for child agents
);

Any idea to implement in future

[moonbox3]

Interesting though. What would the advantage be of connecting "child agents" to a ChatClientAgent? Is it still a parent <-> child agent relationship? Is a childAgentA <-> allowed to talk to childAgentB? If so, we support that in our handoff orchestration pattern now.