U.S. stock benchmarks moved lower on Wednesday as questions linger about how much longer the AI rally can run and as higher oil prices offset recent gains.

The S&P 500 declined 0.2% from its prior record close, while the Nasdaq 100 briefly traded down as much as 1% intraday and finished the session about 0.2% lower. Brent crude settled near $100 a barrel as tensions in the Strait of Hormuz intensified and Middle East oil shipments stayed resilient.

The 10-year U.S. Treasury yield rebounded after a solid $39 billion auction, though yields remained near their highest level in more than two decades. Investors require higher compensation for bond risk amid concerns about inflation, government spending and corporate debt linked to AI expansion.

Money markets are pricing in a relatively high probability that the Federal Reserve will raise rates again before the end of 2026. Minutes from the central bank's September meeting showed all 19 officials supported the rate increase, with many participants saying another hike could help curb inflationary pressures.

Some analysts saw room for one more rate move this year even as policy remains accommodative, while others noted the minutes reflected a broad range of views among participants.

The AI bubble debate persisted, rattling confidence in parts of the market that led gains in recent years. Bridgewater founder Ray Dalio warned that AI is in a classic bubble and could peak as rates rise and investors tighten spending on risk assets.

The IMF warned about risks from AI, persistent energy shocks and the global debt load. Investors are turning to upcoming earnings reports to assess whether corporate profits can sustain elevated valuations amid macro headwinds and ongoing AI investment.