I conducted a test last year with GPT 4. The idea was simple. Feed Powell's official fed meeting speeches and give a rating between 1 and 10, 10 being more dovish and 1 being more hawkish. I fed around 7 or so Fed speeches and kept getting around an 8 on the rating, which would have been more dovish. There were a few speeches in there that were definitely hawkish, and the markets reacted that way as well.

Although my simple test didn't prove anything, I'm 100% sure there is value here and if I had more time I would attempt to exploit it. I collect data from financial social platforms that assign bearish/neutral/bullish ratings and there are highly correlated markers of impending market movements when certain conditions are met. I'm sure fed speeches can be used in the same way for indicators.