diff --git a/NAMESPACE b/NAMESPACE
index fe13d26a..8419ec7d 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -38,6 +38,7 @@ export(local_mock)
 export(local_mocked_responses)
 export(local_verbosity)
 export(multi_req_perform)
+export(new_response)
 export(oauth_cache_clear)
 export(oauth_cache_path)
 export(oauth_client)
diff --git a/NEWS.md b/NEWS.md
index 2d86514a..a2c6dc5a 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,6 @@
 # httr2 (development version)
 
+* `new_response()` is now exported (#751).
 * URL construction is now powered by `curl::curl_modify_url()`, and hence now (correctly) escapes the `path` component (#732). This means that `req_url_path()` now can only affect the path component of the URL, not the query params or fragment.
 * Redacted headers are no longer serialized to disk. This is important since it makes it harder to accidentally leak secrets to files on disk, but comes at a cost: you can longer perform such requests that have been saved and reloaded (#721).
 * New `req_get_method()` and `req_get_body()` allow you to do some limited prediction of what a request _will_ do when it's performed (#718).
diff --git a/R/req-mock.R b/R/req-mock.R
index b05c4912..0ab73f85 100644
--- a/R/req-mock.R
+++ b/R/req-mock.R
@@ -1,8 +1,10 @@
 #' Temporarily mock requests
 #'
 #' Mocking allows you to selectively and temporarily replace the response
-#' you would typically receive from a request with your own code. It's
-#' primarily used for testing.
+#' you would typically receive from a request with your own code. These
+#' functions are low-level and we don't recommend using them directly.
+#' Instead use package that uses these functions under the hood, like
+#' \pkg{httptest2} or \pkg{vcr}.
 #'
 #' @param mock A function, a list, or `NULL`.
 #'
diff --git a/R/resp.R b/R/resp.R
index 1c998103..94188028 100644
--- a/R/resp.R
+++ b/R/resp.R
@@ -1,27 +1,16 @@
-#' Create a new HTTP response
+#' Create a HTTP response for testing
 #'
 #' @description
-#' Generally, you should not need to call this function directly; you'll
-#' get a real HTTP response by calling [req_perform()] and friends. This
-#' function is provided primarily for testing, and a place to describe
-#' the key components of a response.
-#'
 #' `response()` creates a generic response; `response_json()` creates a
-#' response with a JSON body, automatically adding the correct Content-Type
+#' response with a JSON body, automatically adding the correct `Content-Type`
 #' header.
 #'
-#' @keywords internal
-#' @param status_code HTTP status code. Must be a single integer.
-#' @param url URL response came from; might not be the same as the URL in
-#'   the request if there were any redirects.
-#' @param method HTTP method used to retrieve the response.
-#' @param headers HTTP headers. Can be supplied as a raw or character vector
-#'   which will be parsed using the standard rules, or a named list.
-#' @param body Response, if any, contained in the response body.
-#'   For `response_json()`, a R data structure to serialize to JSON.
-#' @param timing A named numeric vector giving the time taken by various
-#'   components.
-#' @returns An HTTP response: an S3 list with class `httr2_response`.
+#' Generally, you should not need to call these function directly; you'll
+#' get a real HTTP response by calling [req_perform()] and friends. These
+#' function is provided primarily for use in tests; if you are creating
+#' responses for mocked requests, use the lower-level [new_response()].
+#'
+#' @inherit new_response params return
 #' @export
 #' @examples
 #' response()
@@ -40,6 +29,10 @@ response <- function(
   check_string(method)
 
   headers <- as_headers(headers)
+  # ensure we always have a date field
+  if (!"date" %in% tolower(names(headers))) {
+    headers$Date <- "Wed, 01 Jan 2020 00:00:00 UTC"
+  }
 
   new_response(
     method = method,
@@ -74,6 +67,25 @@ response_json <- function(
   )
 }
 
+#' Create a HTTP response
+#'
+#' This is the constructor function for the `httr2_response` S3 class. It is
+#' useful primarily for mocking.
+#'
+#' @param method HTTP method used to retrieve the response.
+#' @param url URL response came from; might not be the same as the URL in
+#'   the request if there were any redirects.
+#' @param status_code HTTP status code. Must be a single integer.
+#' @param headers HTTP headers. Can be supplied as a raw or character vector
+#'   which will be parsed using the standard rules, or a named list.
+#' @param body Response, if any, contained in the response body.
+#'   For `response_json()`, a R data structure to serialize to JSON.
+#' @param timing A named numeric vector giving the time taken by various
+#'   components.
+#' @param request The [request] used to generate this response.
+#' @param error_call Environment (on call stack) used in error messages.
+#' @returns An HTTP response: an S3 list with class `httr2_response`.
+#' @export
 new_response <- function(
   method,
   url,
@@ -87,15 +99,22 @@ new_response <- function(
   check_string(method, call = error_call)
   check_string(url, call = error_call)
   check_number_whole(status_code, call = error_call)
-  check_request(request, allow_null = TRUE)
+  check_request(request, allow_null = TRUE, call = error_call)
   if (!is.null(timing) && !is_bare_numeric(timing)) {
-    stop_input_type(timing, "a numeric vector", allow_null = TRUE)
+    stop_input_type(
+      timing,
+      "a numeric vector",
+      allow_null = TRUE,
+      call = error_call
+    )
   }
-
   headers <- as_headers(headers, error_call = error_call)
-  # ensure we always have a date field
-  if (!"date" %in% tolower(names(headers))) {
-    headers$Date <- "Wed, 01 Jan 2020 00:00:00 UTC"
+  if (!is.raw(body) && !is_path(body) && !inherits(body, "connection")) {
+    stop_input_type(
+      body,
+      "a raw vector, a path, or a connection",
+      call = error_call
+    )
   }
 
   structure(
diff --git a/_pkgdown.yml b/_pkgdown.yml
index dacbe7d9..be0c3bc7 100644
--- a/_pkgdown.yml
+++ b/_pkgdown.yml
@@ -33,7 +33,6 @@ reference:
       - last_request
       - req_dry_run
       - req_verbose
-      - with_mock
       - with_verbosity
 
   - subtitle: Authentication
@@ -78,8 +77,6 @@ reference:
     contents:
       - curl_translate
       - is_online
-      - secrets
-      - obfuscate
 
   - title: OAuth
     desc: >
@@ -88,6 +85,16 @@ reference:
       - starts_with("oauth_")
       - -starts_with("req_oauth")
 
+  - title: Package development
+    desc: >
+      These functions are useful when developing packges that use httr2.
+    contents:
+      - with_mock
+      - secrets
+      - obfuscate
+      - response
+      - new_response
+
 articles:
   - title: Using httr2
     navbar: ~
diff --git a/man/new_response.Rd b/man/new_response.Rd
new file mode 100644
index 00000000..6d416b4c
--- /dev/null
+++ b/man/new_response.Rd
@@ -0,0 +1,45 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/resp.R
+\name{new_response}
+\alias{new_response}
+\title{Create a HTTP response}
+\usage{
+new_response(
+  method,
+  url,
+  status_code,
+  headers,
+  body,
+  timing = NULL,
+  request = NULL,
+  error_call = caller_env()
+)
+}
+\arguments{
+\item{method}{HTTP method used to retrieve the response.}
+
+\item{url}{URL response came from; might not be the same as the URL in
+the request if there were any redirects.}
+
+\item{status_code}{HTTP status code. Must be a single integer.}
+
+\item{headers}{HTTP headers. Can be supplied as a raw or character vector
+which will be parsed using the standard rules, or a named list.}
+
+\item{body}{Response, if any, contained in the response body.
+For \code{response_json()}, a R data structure to serialize to JSON.}
+
+\item{timing}{A named numeric vector giving the time taken by various
+components.}
+
+\item{request}{The \link{request} used to generate this response.}
+
+\item{error_call}{Environment (on call stack) used in error messages.}
+}
+\value{
+An HTTP response: an S3 list with class \code{httr2_response}.
+}
+\description{
+This is the constructor function for the \code{httr2_response} S3 class. It is
+useful primarily for mocking.
+}
diff --git a/man/response.Rd b/man/response.Rd
index f0eb95a0..7dc2874b 100644
--- a/man/response.Rd
+++ b/man/response.Rd
@@ -3,7 +3,7 @@
 \name{response}
 \alias{response}
 \alias{response_json}
-\title{Create a new HTTP response}
+\title{Create a HTTP response for testing}
 \usage{
 response(
   status_code = 200,
@@ -43,18 +43,17 @@ components.}
 An HTTP response: an S3 list with class \code{httr2_response}.
 }
 \description{
-Generally, you should not need to call this function directly; you'll
-get a real HTTP response by calling \code{\link[=req_perform]{req_perform()}} and friends. This
-function is provided primarily for testing, and a place to describe
-the key components of a response.
-
 \code{response()} creates a generic response; \code{response_json()} creates a
-response with a JSON body, automatically adding the correct Content-Type
+response with a JSON body, automatically adding the correct \code{Content-Type}
 header.
+
+Generally, you should not need to call these function directly; you'll
+get a real HTTP response by calling \code{\link[=req_perform]{req_perform()}} and friends. These
+function is provided primarily for use in tests; if you are creating
+responses for mocked requests, use the lower-level \code{\link[=new_response]{new_response()}}.
 }
 \examples{
 response()
 response(404, method = "POST")
 response(headers = c("Content-Type: text/html", "Content-Length: 300"))
 }
-\keyword{internal}
diff --git a/man/with_mocked_responses.Rd b/man/with_mocked_responses.Rd
index f0190605..7cdbb12d 100644
--- a/man/with_mocked_responses.Rd
+++ b/man/with_mocked_responses.Rd
@@ -31,8 +31,10 @@ handle the request) or a \link{response} (if it does).
 }
 \description{
 Mocking allows you to selectively and temporarily replace the response
-you would typically receive from a request with your own code. It's
-primarily used for testing.
+you would typically receive from a request with your own code. These
+functions are low-level and we don't recommend using them directly.
+Instead use package that uses these functions under the hood, like
+\pkg{httptest2} or \pkg{vcr}.
 }
 \examples{
 # This function should perform a response against google.com:
diff --git a/tests/testthat/_snaps/resp.md b/tests/testthat/_snaps/resp.md
index a8e851fe..05cf1fa1 100644
--- a/tests/testthat/_snaps/resp.md
+++ b/tests/testthat/_snaps/resp.md
@@ -52,3 +52,41 @@
       Error:
       ! `1` must be an HTTP response object, not the number 1.
 
+# new_response() checks its inputs
+
+    Code
+      new_response(1)
+    Condition
+      Error:
+      ! `method` must be a single string, not the number 1.
+    Code
+      new_response("GET", 1)
+    Condition
+      Error:
+      ! `url` must be a single string, not the number 1.
+    Code
+      new_response("GET", "http://x.com", "x")
+    Condition
+      Error:
+      ! `status_code` must be a whole number, not the string "x".
+    Code
+      new_response("GET", "http://x.com", 200, 1)
+    Condition
+      Error:
+      ! `headers` must be a list, character vector, or raw.
+    Code
+      new_response("GET", "http://x.com", 200, list(), 1)
+    Condition
+      Error:
+      ! `body` must be a raw vector, a path, or a connection, not the number 1.
+    Code
+      new_response("GET", "http://x.com", 200, list(), raw(), "x")
+    Condition
+      Error:
+      ! `timing` must be a numeric vector or `NULL`, not the string "x".
+    Code
+      new_response("GET", "http://x.com", 200, list(), raw(), c(x = 1), 1)
+    Condition
+      Error:
+      ! `request` must be an HTTP request object or `NULL`, not the number 1.
+
diff --git a/tests/testthat/test-resp.R b/tests/testthat/test-resp.R
index 2c2030b5..934bb090 100644
--- a/tests/testthat/test-resp.R
+++ b/tests/testthat/test-resp.R
@@ -24,3 +24,15 @@ test_that("response adds date if not provided by server", {
 test_that("check_response produces helpful error", {
   expect_snapshot(check_response(1), error = TRUE)
 })
+
+test_that("new_response() checks its inputs", {
+  expect_snapshot(error = TRUE, {
+    new_response(1)
+    new_response("GET", 1)
+    new_response("GET", "http://x.com", "x")
+    new_response("GET", "http://x.com", 200, 1)
+    new_response("GET", "http://x.com", 200, list(), 1)
+    new_response("GET", "http://x.com", 200, list(), raw(), "x")
+    new_response("GET", "http://x.com", 200, list(), raw(), c(x = 1), 1)
+  })
+})