Federal Reserve Chairman Kevin Warsh has spent months projecting a tough stance on inflation. Yet his refusal to signal a clear plan for follow-through has left Wall Street questioning whether he is genuinely committed to price stability.

Markets barely moved when the Fed announced on Wednesday that it would hold rates unchanged, as most investors had already anticipated a steady policy. The real reaction came during Warsh's post-meeting press conference, where his remarks triggered a Treasury selloff that drove yields sharply higher.

Warsh has pledged what he calls a "regime change" at the Fed, centered on rolling back forward guidance — the practice of signaling the likely path of interest rates. The tool became a cornerstone of Fed communication over the post-2008 era, when chairmen from Bernanke through Yellen used it to anchor market expectations during years of near-zero rates. On Wednesday, Warsh offered no such direction, sidestepping even straightforward questions about how the central bank intends to bring inflation down.

Further unsettling investors, Warsh signaled openness to alternative inflation gauges beyond the Fed's preferred measure — the Personal Consumption Expenditures price index, which the central bank formally targets at 2 percent over the long run — and suggested that tools other than rate hikes could be deployed. He also implied that rising bond yields had already accomplished part of the Fed's tightening work.

The strategy backfired. Aditya Bhave and the U.S. economy team at Bank of America described the result as a "central bank inflation credibility shock."

"Ironically, we think the need to re-establish credibility increases the probability that the Fed will hike in September, all else equal," Bhave added in a note published Wednesday.

In effect, Warsh's dovish tone may force a hawkish outcome, with other members of the rate-setting Federal Open Market Committee left to repair the damage.

JPMorgan economist Michael Feroli wrote in a note that the chairman's comments about looking beyond the Fed's preferred inflation gauge likely did not sit well with all FOMC members. "It is those members who we believe will vote to take action to deliver on the institution's mandate," Feroli said.

A critical test for the Fed arrives Friday, when the Labor Department releases its monthly payroll report. Signs of continued labor market strength could intensify concerns about persistent inflation. The data will feed directly into the Fed's assessment ahead of its next scheduled meeting, where the FOMC will have to decide whether Warsh's open-ended approach can stand or whether the committee needs to supply the clarity the chairman withheld.

Bank of America pointed to the bond yield curve as a barometer of market confidence in the Fed's anti-inflation resolve. If investors expect near-term rate hikes, short-term yields rise while long-term yields fall as markets price in lower future inflation — flattening the curve across maturities. Conversely, if markets doubt the Fed's commitment, the short end falls and the long end surges.

"Flattening of the curve would mean markets still believe the Fed will do what it takes to meet its mandate," BofA economists said. "But if the curve were to steepen on strong jobs/inflation data, that would indicate the Fed is behind the curve, raising more serious questions about its credibility."

Apollo Chief Economist Torsten Slok emphasized that backing tough rhetoric with concrete details is essential to the Fed's credibility. In a Saturday note, he drew an analogy to promising someone a trip from New York to Los Angeles without specifying the duration, cost, or mode of transportation — inevitably raising doubts about whether the trip will happen at all.

"The risk with abandoning forward guidance is a steeper yield curve with investors asking more questions about the journey ahead, which is what we have seen since the statement came out," Slok said. "The bottom line is that an important part of the Fed's credibility is not just to say that it has certain goals but also to explain how it will achieve those goals."