what do I add to a `ggplot(... geom_smooth(method=lm))`

form of argument to get it to display the gradient of the regression line as a number on the graph?

what would be even better is if R could return the gradient of the regression directly to the console along with the graph when the script runs.

apologies for the weird question with no reproducible examples provided im only looking for a very general method here, the specifics of my case are irrelevant and difficult to explain