Debugging bad splines during construction

I don't want to type out the whole game pitch here (it's long), but let's just say that it's a game where cars and buses roam around the streets. Kinda like Cities: Skylines.

"Bad splines" in my game means that the curve is too tight for long buses.

https://imgur.com/a/PLVj63H

The roads are made using a spline mesh component. The one on the right is fine, the one on the left should be "throwing" an error at the spline points where the curve is too tight. My gut tells me that the answer is related to the tangents of the path at the bad spline points, but I'm not sure where to begin with that.

The errors need to be highlighted during construction (not PIE) because I'll be building a lot of roads for the game and I don't have the patience to load PIE every single time I make a change.

ps: Yes, I tried AI. Claude gave me a long-ass BP function that kept claiming "yes your BP is correct" when I gave it the image of the BP. It was not.