The difference between answering and doing
A support agent trained only on your documentation can tell a customer what your refund policy is. It cannot tell them whether *their* refund has been processed. That second question is the one people actually ask, and it is the one that ends in a support ticket.
An action closes that gap. You describe one endpoint you already own, the agent works out when a question needs it, extracts the parameters from what the customer said, calls it, and answers from the response. The agent is not guessing. It is reading your system, at the moment it is asked.
This is what separates deflection from automation. A chatbot that deflects sends people to a help article. A chatbot with actions resolves the thing they came for and closes the conversation.