I recently stumbled upon ts-rest which is a contract library, you create a with subcontracts from which you can derive clients which each have their methods, I personally think it's easier and less work that generating clients methods

Sorry if that's not very clear, better read : https://ts-rest.com/docs/intro

Also, it integrates well with OpenAPI to document the API

I am using it between NestJs and SvelteKit and it's great