The hourly chart puts the SPX is a good context for understanding this bounce/retracement. There are virtually no shorts here to run, so the algos are likely to pack up and see what happens. The caution point is where the hourly Cycle Top at 2185.15 and short-term trendline lay.
A reversal/pivot here may give the SPX the momentum to break the next trendline support at 2171.00. Mid-Cycle support is just beneath it at 2169.26, so we may wish to use it as our next short entry point.