Cashu is much faster. It can be minted by paying a lightning invoice. But we don't have to theorize, there's athenut for search and another project for cashu based ai based on openrouter. Both are open source, so you can just use the code today.
Discussion
Where can I pay a lightning invoice to to get bearer key that I can use on routstr?

Bearer key? Lightning invoice?
Your request, granted:
Use nutshell as a library.
You want a mint call.
I'm asking from the perspective of a normal non-dev user who just knows how to send lightning invoices. I don't want to have to install libraries and do function calls.
How does a normie use routstr when the normy only knows how to send lightning invoices?
If you can do API calls to access this, you can do one more to mint a token. Also, minibits or cashu.me will mint you tokens in exchange for lightning invoice in a normie friendly way.
If you are a normie, you need a user interface that someone builds for you and shows you the invoice. Athenut does this in a nice way, you don't even see tokens, only the invoice.
But please don't be a normie. If you can use AI, you can use the library. Learn. Normies will have a very hard time in what's coming at them. The normie way leads to a Disneyland themed gulag. You should expect more of yourself and for yourself.