Large language models (LLMs), such as GPT-4 or Claude 3, can do many things that were very hard to do only a couple of years ago, especially in interpreting and generating natural language. They become even more powerful with simple wrappers around them such as ChatGPT, that allow them to use external tools: for example, to execute code or search the web. An LLM surrounded by such a wrapper is called an "AI Agent".