microsoft/semantic-kernel ? reverse-engineered prompt

Build me a library that helps me create my own AI agents. The main idea is that these agents shouldn't just be simple chatbots; I need to be able to give them custom tools and functions to work with. For example, I want to be able to give an agent a tool that can look up menu specials and prices, and it should be smart enough to automatically use that tool when a user asks "what's the price of the soup special?".

It should be flexible, allowing me to connect to different AI models like the ones from OpenAI and Azure. I'd also like the ability to orchestrate multiple agents so they can work together to solve more complex problems. Please build out the core framework and provide example code in both Python and C# showing how to create a basic agent and another one that uses a custom plugin, just like that menu example.