io

 import cats.effect.IO
 import org.http4s._
 import org.http4s.client._
 import org.http4s.client.io._
 import org.http4s.Http4s._
 import org.http4s.Status._
 import org.http4s.Method._
 import org.http4s.EntityDecoder

 def client: Client[IO] = ???

 val r: IO[String] = client(GET(uri("https://www.foo.bar/"))).as[String]
 val r2: DecodeResult[String] = client(GET(uri("https://www.foo.bar/"))).attemptAs[String] // implicitly resolve the decoder
 val req1 = r.unsafeRunSync()
 val req2 = r.unsafeRunSync() // Each invocation fetches a new Result based on the behavior of the Client