Trial and error. So far, the only issues I've encountered are small oversights, not critical errors.
I did try working with codex (I think I used ChatGPT back then?) some 16 months ago, and half of the things I wanted to do ended up in a mess. Astra is the first one that seems to be actually somewhat usable (edit: but it's also like 10-20x more expensive, I run into limits under 20€ subscription quite fast)
On related note - It makes me uncomfortable to admit this, but the progress blows my mind away and it makes me uncomfortable, by now I truly believe it's there to stay and will make so many jobs obsolete. I was part of the AI hating club 1 month ago, and cognitive dissonance is real