Refining a Schema with a Type to Create a Literal Schema

is it possible to refine a schema with a type? for example, create a schema equivalent to

Schema.Literal<"a" | "b">

Schema.Literal<"a" | "b">

from just the type

"a" | "b"

"a" | "b"

Refining a Schema with a Type to Create a Literal Schema - Effect Community