This repository contains the Microsoft 365 Agents SDK and samples for building conversational agents deployable to Microsoft 365 channels (Teams, Copilot Studio, web chat) and custom channels. The SDK is AI-service agnostic, allowing integration of any AI model or service. Samples demonstrate common agent patterns including welcome messages, tool usage (dice roller, inventory, weather lookup), streaming responses, authentication (OBO, auto sign-in), observability (OpenTelemetry), and integrations (Genesys, Slack, Semantic Kernel, LangChain). The architecture follows a consistent pattern across languages: initialize storage, connection manager, adapter, and authorization; instantiate AgentApplication; register event handlers; start server. Entry points vary by language (Program.cs for .NET, src/index.ts for Node.js, src/main.py for Python). External dependencies include Microsoft Graph, GitHub API, Azure OpenAI, and various agent frameworks.