User intent is a classification problem. By giving the LLM model different examples of classifications, it can help simplify the process, since LLMs understand nuances.
For example, by classifying the difference between booking a ticket and booking a restaurant, LLMs can understand that “booking a table” means “booking a restaurant”, even though there is no use of the word “restaurant” in the statement.
For more information, NLP has a vast amount of literature dedicated to determining the most efficient classification technique to recognize user intent from a sentence.