Choosing Between `Effect.sync` and `Effect.promise` for Functions with the Same Signature

Question about knowing when to run an Effect with
Effect.sync
or Effect.runPromise: if you're getting an Effect from a function, how would you know which to use if both async and synchronous Effects have the same signature?

I'm thinking there has to be a way without looking at a function's implementation. In fp-ts, you would know because the function's return signature would be a Task, TaskEither, or IO.
Was this page helpful?