You can search for identifiers within the package.
in-package search v0.2.0
ltac2_plugin
Tac2ffi.Valexpr
type t = valexpr
val is_int : t -> bool
val tag : t -> int
val field : t -> int -> t
val set_field : t -> int -> t -> unit
val make_block : int -> t array -> t
val make_int : int -> t