Inside the Fed, it's steady-as-she-goes. Investors see this week's meeting as an easy call, with officials set to vote for leaving their policy rate unchanged for now.

Outside, the conversation is quite different. Former policymakers and veteran Fed watchers are increasingly preoccupied with what the central bank will be able to do, and the tools it will need, when the next downturn arrives.

The debate keeps throwing up bold new ideas—from direct cash injections to a digital dollar to explicit coordination between central bankers and the politicians who control budgets, an idea floated by JPMorgan Chase & Co. chief Jamie Dimon in Davos last week. And the Fed is, in fact, halfway through a review of tools and communications, a discussion that may feature prominently at the meeting tomorrow and Wednesday.