diff --git a/pkgs/net-pkgs/net-doc/net/scribblings/http-client.scrbl b/pkgs/net-pkgs/net-doc/net/scribblings/http-client.scrbl
index 8eae5868d8..ec088d119e 100644
--- a/pkgs/net-pkgs/net-doc/net/scribblings/http-client.scrbl
+++ b/pkgs/net-pkgs/net-doc/net/scribblings/http-client.scrbl
@@ -83,8 +83,8 @@ additional headers given in @racket[headers] and the additional data
 @racket[data].
 
 If @racket[data] is a procedure, it will be called once with a
-procedure of one argument, which is a @racket[string] or
-@racket[byte-string] to be written to the request body using
+procedure of one argument, which is a string or
+byte string to be written to the request body using
 chunked transfer encoding.
 
 If @racket[headers] does not contain an @litchar{Accept-Encoding}
@@ -151,6 +151,14 @@ response, which is why there is no @racket[#:closed?] argument like
 
 }
 
+@defthing[data-procedure/c chaperone-contract?]{
+
+Contract for a procedure that accepts a procedure of one
+argument, which is a string or byte string:
+@racket[(-> (-> (or/c bytes? string?) any/c) any/c)].
+
+}
+
 @section[#:tag "faq"]{Troubleshooting and Tips}
 
 @subsection{How do I send properly formatted POST form requests?}