You can search for identifiers within the package.
in-package search v0.2.0
type cert_id = X509.OCSP.cert_id
val create_cert_id : ?hash:Mirage_crypto.Hash.hash -> X509.Certificate.t -> Z.t -> cert_id
val cert_id_serial : cert_id -> Z.t
val pp_cert_id : cert_id Fmt.t
module Request : sig ... end
module Response : sig ... end