The useful distinction is not old versus new. RPA fails when the work requires understanding; agents fail when the work requires exactness. Most real processes contain both, which is why the productive question is which step is which.

Rules first, model only where judgment is needed

A workflow should use the cheapest mechanism that is correct. Deterministic routing, validation and system updates belong in rules — they are faster, cheaper and testable. Reserve the model for the step where a human would otherwise have to read something and decide. Workflows built this way have far fewer places to go wrong, and each of those places is identifiable.

Both need a defined failure path

The difference shows up when something is unexpected. Classic RPA stops, and the queue silently grows until somebody notices. A well-built agent workflow escalates with context to a named owner. Neither is safe by default: whichever you choose, the exception path and the person who owns it have to be designed on purpose.

For the related distinction between agents, chatbots and plain workflow automation, see the guide linked below.