You can search for identifiers within the package.
in-package search v0.2.0
module Signal : sig ... end
module Exit : sig ... end
module Output : sig ... end
module type S = sig ... end
include S with type 'a io = 'a
type 'a io = 'a
val run : ?stdin:Bytes.t -> ?exit_status:int list -> string -> string array -> Output.t io
val read_stdout : ?stdin:Bytes.t -> ?exit_status:int list -> string -> string array -> string list io