How do i set maximum length for my String fields ?

That not something that is GraphQL's job to decide. If you want to do validation I can recommend

joi

or something similar.

thanks, Prisma itself as an ORM doesn't have any solution for this ?!

Afaik, no. I think by default the type is

TEXT

, so it's uncapped.

Hmm that seems to be right, Tnx 👍