diff --git a/internal/server/control/control_test.go b/internal/server/control/control_test.go
index c40b70b..9d1738d 100644
--- a/internal/server/control/control_test.go
+++ b/internal/server/control/control_test.go
@@ -130,7 +130,7 @@ func TestAddRouteReturnsBadRequestWhenMalformedJSONBody(t *testing.T) {
 	addRoute(resp, req)
 
 	for _, e := range checkErrorResponse(resp.Result(), http.StatusBadRequest, "Malformed JSON") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
@@ -194,7 +194,7 @@ func TestAddRouteReturns422ErrorWhenMandatoryFieldsMissing(t *testing.T) {
 		r := resp.Result()
 		if test.testMustFail {
 			for _, e := range checkErrorResponse(r, http.StatusUnprocessableEntity, "Invalid Route") {
-				t.Error(e.Error())
+				t.Error(e)
 			}
 		} else if !test.testMustFail {
 			if r.StatusCode != http.StatusCreated {
@@ -258,7 +258,7 @@ func TestAddRoute500sWhenIDGeneratorFails(t *testing.T) {
 	addRoute(resp, req)
 
 	for _, e := range checkErrorResponse(resp.Result(), http.StatusInternalServerError, "Internal Server Error") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
@@ -324,7 +324,7 @@ func TestAddRoute422sWhenInvalidRoute(t *testing.T) {
 	addRoute(resp, req)
 
 	for _, e := range checkErrorResponse(resp.Result(), http.StatusUnprocessableEntity, "Invalid Route") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
@@ -345,7 +345,7 @@ func TestRemoveRouteReturnsNotFound(t *testing.T) {
 	handler.ServeHTTP(resp, req)
 
 	for _, e := range checkErrorResponse(resp.Result(), http.StatusNotFound, "Route Not Found") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
@@ -436,7 +436,7 @@ func TestGetRouteReturns404sWhenRouteDoesntExist(t *testing.T) {
 	handler.ServeHTTP(w, r)
 
 	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Route Not Found") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
diff --git a/internal/server/data/decorator_test.go b/internal/server/data/decorator_test.go
index 420b7bb..1c75cdd 100644
--- a/internal/server/data/decorator_test.go
+++ b/internal/server/data/decorator_test.go
@@ -128,7 +128,7 @@ func TestCheckHandlerReturnsAFunctionsThat404sWhenHandlerDoesNotExist(t *testing
 	fn(w, r)
 
 	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Handler ID Not Found") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
 
diff --git a/internal/server/data/resource.go b/internal/server/data/resource.go
index caf3e13..d55fc72 100644
--- a/internal/server/data/resource.go
+++ b/internal/server/data/resource.go
@@ -28,12 +28,18 @@ import (
 	"github.com/gorilla/mux"
 )
 
+const (
+	ResourceItemNotFound = "Resource Item Not Found"
+	NonIntegerValue      = "Non Integer Value"
+	InvalidStatusCode    = "Invalid Status Code"
+)
+
 func getRequestBody(w http.ResponseWriter, r *http.Request, h *model.Handler) {
 	w.Header().Add("Content-Type", "application/octet-stream")
 	n, err := io.Copy(w, h.Request.Body)
 	if err != nil {
 		if n == 0 {
-			srverrors.WriteErrorResponse(http.StatusInternalServerError, "Internal Server Error", w)
+			srverrors.WriteErrorResponse(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError), w)
 		} else {
 			// Only way to abort current connection as of go 1.13
 			// https://github.com/golang/go/issues/16542
@@ -65,7 +71,7 @@ func getRequestMatches(w http.ResponseWriter, r *http.Request, h *model.Handler)
 	if value, ok := vars[name]; ok {
 		_, _ = w.Write([]byte(value))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -75,7 +81,7 @@ func getRequestParams(w http.ResponseWriter, r *http.Request, h *model.Handler)
 	if values, ok := h.Request.URL.Query()[name]; ok {
 		_, _ = w.Write([]byte(values[0]))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -85,7 +91,7 @@ func getRequestHeaders(w http.ResponseWriter, r *http.Request, h *model.Handler)
 	if values, ok := h.Request.Header[textproto.CanonicalMIMEHeaderKey(name)]; ok {
 		_, _ = w.Write([]byte(values[0]))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -95,7 +101,7 @@ func getRequestCookies(w http.ResponseWriter, r *http.Request, h *model.Handler)
 	if cookie, err := h.Request.Cookie(name); err == nil {
 		_, _ = w.Write([]byte(cookie.Value))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -111,11 +117,11 @@ func getRequestForm(w http.ResponseWriter, r *http.Request, h *model.Handler) {
 	// We tried to exercise this execution path but didn't know how.
 	err := h.Request.ParseForm()
 	if err != nil {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	} else if values, ok := h.Request.Form[name]; ok {
 		_, _ = w.Write([]byte(values[0]))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -126,7 +132,7 @@ func getRequestFileName(w http.ResponseWriter, r *http.Request, h *model.Handler
 	if err == nil {
 		_, _ = w.Write([]byte(header.Filename))
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -137,7 +143,7 @@ func getRequestFileContent(w http.ResponseWriter, r *http.Request, h *model.Hand
 	if err == nil {
 		_, _ = io.Copy(w, file)
 	} else {
-		w.WriteHeader(http.StatusNotFound)
+		srverrors.WriteErrorResponse(http.StatusNotFound, ResourceItemNotFound, w)
 	}
 }
 
@@ -146,17 +152,16 @@ func getRequestFileContent(w http.ResponseWriter, r *http.Request, h *model.Hand
 func setResponseStatus(w http.ResponseWriter, r *http.Request, h *model.Handler) {
 	sb, err := ioutil.ReadAll(r.Body)
 	if err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
+		srverrors.WriteErrorResponse(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError), w)
 		return
 	}
 
-	si, err := strconv.Atoi(string(sb))
-	if http.StatusText(si) == "" {
-		w.WriteHeader(http.StatusBadRequest)
-	} else if err == nil {
-		h.Writer.WriteHeader(int(si))
+	if si, err := strconv.Atoi(string(sb)); err != nil {
+		srverrors.WriteErrorResponse(http.StatusUnprocessableEntity, NonIntegerValue, w)
+	} else if http.StatusText(si) == "" {
+		srverrors.WriteErrorResponse(http.StatusBadRequest, InvalidStatusCode, w)
 	} else {
-		w.WriteHeader(http.StatusBadRequest)
+		h.Writer.WriteHeader(int(si))
 	}
 }
 
@@ -164,7 +169,7 @@ func setResponseHeaders(w http.ResponseWriter, r *http.Request, h *model.Handler
 	name := mux.Vars(r)["name"]
 	vb, err := ioutil.ReadAll(r.Body)
 	if err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
+		srverrors.WriteErrorResponse(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError), w)
 		return
 	}
 
@@ -180,7 +185,7 @@ func setResponseCookies(w http.ResponseWriter, r *http.Request, h *model.Handler
 	name := mux.Vars(r)["name"]
 	vb, err := ioutil.ReadAll(r.Body)
 	if err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
+		srverrors.WriteErrorResponse(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError), w)
 		return
 	}
 
@@ -193,6 +198,6 @@ func setResponseBody(w http.ResponseWriter, r *http.Request, h *model.Handler) {
 		if n > 0 {
 			panic("Truncated body")
 		}
-		w.WriteHeader(http.StatusInternalServerError)
+		srverrors.WriteErrorResponse(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError), w)
 	}
 }
diff --git a/internal/server/data/resource_test.go b/internal/server/data/resource_test.go
index 73e7c32..7ed8fae 100644
--- a/internal/server/data/resource_test.go
+++ b/internal/server/data/resource_test.go
@@ -121,8 +121,8 @@ func TestGetRequestBody500sWhenHandlerRequestErrors(t *testing.T) {
 
 	getRequestBody(w, r, &h)
 
-	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, "Internal Server Error") {
-		t.Error(e.Error())
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
@@ -369,9 +369,8 @@ func TestGetRequestMatchesReturnsNotFoundWhenMatchDoesntExists(t *testing.T) {
 
 	getRequestMatches(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404. Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -433,9 +432,8 @@ func TestGetRequestParams404sWhenParamDoesntExist(t *testing.T) {
 
 	getRequestParams(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404. Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -478,14 +476,15 @@ func TestGetRequestHeadersSetsOctectStreamContentType(t *testing.T) {
 		Request: httptest.NewRequest("GET", "/", nil),
 		Writer:  httptest.NewRecorder(),
 	}
+	h.Request.Header.Set("bar", "BAZ")
 	r := createMuxRequest("/handlers/HANDLERID/request/headers/{name}", "/handlers/HANDLERID/request/headers/bar", "GET", nil)
 	w := httptest.NewRecorder()
 
 	getRequestHeaders(w, r, &h)
 
 	res := w.Result()
-	if res.Header.Get("Content-Type") != "application/octet-stream" {
-		t.Error("Content Type mismatch")
+	if v := res.Header.Get("Content-Type"); v != "application/octet-stream" {
+		t.Errorf("Content Type mismatch. Expected: application/octet-stream. Got: %q", v)
 	}
 }
 
@@ -567,9 +566,8 @@ func TestGetRequestHeaders404sWhenHeaderDoesntExist(t *testing.T) {
 
 	getRequestHeaders(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Error("Status code mismatch")
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -652,9 +650,8 @@ func TestGetRequestCookies404sIfCookieDoesntExist(t *testing.T) {
 
 	getRequestCookies(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -754,9 +751,8 @@ func TestGetRequestForm404sWhenFieldDoesntExist(t *testing.T) {
 
 	getRequestForm(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -810,9 +806,8 @@ func TestGetRequestForm404sWhenFormDoesntExist(t *testing.T) {
 
 	getRequestForm(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -885,9 +880,8 @@ func TestGetRequestFileName404sWhenFileDoesntExist(t *testing.T) {
 
 	getRequestFileName(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -902,9 +896,8 @@ func TestGetRequestFileName404sWhenFormDoesntExist(t *testing.T) {
 
 	getRequestFileName(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -966,9 +959,8 @@ func TestGetRequestFileContent404sWhenFileDoesntExist(t *testing.T) {
 
 	getRequestFileContent(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -983,9 +975,8 @@ func TestGetRequestFileContent404sWhenFormDoesntExist(t *testing.T) {
 
 	getRequestFileContent(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusNotFound {
-		t.Errorf("Status code mismatch. Expected: 404, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusNotFound, "Resource Item Not Found") {
+		t.Error(e)
 	}
 }
 
@@ -1009,9 +1000,8 @@ func TestGetRequestFileContent500sWhenHandlerRequestErrors(t *testing.T) {
 
 	getRequestFileContent(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusInternalServerError {
-		t.Error("status not 500", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
@@ -1058,9 +1048,8 @@ func TestSetResponseStatus400sWhenNonparseableStatusCode(t *testing.T) {
 
 	setResponseStatus(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusBadRequest {
-		t.Errorf("Status code mismatch. Expected: 400, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusUnprocessableEntity, "Non Integer Value") {
+		t.Error(e)
 	}
 }
 
@@ -1074,9 +1063,8 @@ func TestSetResponseStatus500sWhenErrorReadingRequest(t *testing.T) {
 
 	setResponseStatus(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusInternalServerError {
-		t.Errorf("Status code mismatch. Expected: 500, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
@@ -1092,9 +1080,8 @@ func TestSetResponseStatus400sWhenStatusCodeNotSupportedByGo(t *testing.T) {
 
 	setResponseStatus(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusBadRequest {
-		t.Errorf("Status code mismatch. Expected: 400, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusBadRequest, "Invalid Status Code") {
+		t.Error(e)
 	}
 }
 
@@ -1162,9 +1149,8 @@ func TestSetResponseHeaders500sWhenErrorReadingRequest(t *testing.T) {
 
 	setResponseHeaders(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusInternalServerError {
-		t.Errorf("Status code mismatch. Expected: 500, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
@@ -1181,9 +1167,8 @@ func TestSetResponseHeaders400sOnInvalidHeaderKey(t *testing.T) {
 
 	setResponseHeaders(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusBadRequest {
-		t.Errorf("Status code mismatch. Expected: 400, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusBadRequest, "Invalid Header Name") {
+		t.Error(e)
 	}
 }
 
@@ -1200,9 +1185,8 @@ func TestSetResponseHeaders400sOnInvalidHeaderValue(t *testing.T) {
 
 	setResponseHeaders(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusBadRequest {
-		t.Errorf("Status code mismatch. Expected: 400, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusBadRequest, "Invalid Header Value") {
+		t.Error(e)
 	}
 }
 
@@ -1250,9 +1234,8 @@ func TestSetResponseCookies500sWhenErrorReadingRequest(t *testing.T) {
 
 	setResponseCookies(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusInternalServerError {
-		t.Errorf("Status code mismatch. Expected: 500, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
@@ -1322,9 +1305,8 @@ func TestSetResponseBody500sWhenReaderFailsInFirstRead(t *testing.T) {
 
 	setResponseBody(w, r, &h)
 
-	res := w.Result()
-	if res.StatusCode != http.StatusInternalServerError {
-		t.Errorf("Status code mismatch. Expected: 500, Got: %d", res.StatusCode)
+	for _, e := range checkErrorResponse(w.Result(), http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError)) {
+		t.Error(e)
 	}
 }
 
diff --git a/internal/server/data/server_test.go b/internal/server/data/server_test.go
index 30cadf5..7481e5a 100644
--- a/internal/server/data/server_test.go
+++ b/internal/server/data/server_test.go
@@ -78,6 +78,6 @@ func TestConfigRouterReturnsRouterThat400sOnUnconfiguredResources(t *testing.T)
 	m.ServeHTTP(w, httptest.NewRequest("GET", "/handlers/FOO/dummy", nil))
 
 	for _, e := range checkErrorResponse(w.Result(), http.StatusBadRequest, "Invalid Resource Path") {
-		t.Error(e.Error())
+		t.Error(e)
 	}
 }
diff --git a/spec/README.md b/spec/README.md
index ba95891..aadca97 100644
--- a/spec/README.md
+++ b/spec/README.md
@@ -554,6 +554,10 @@ path doesn't exist or is invalid.
 * **Error Responses**:
   * **Code**: `400`; Reason: `Invalid Resource Path`<br />
     **Notes**: Check the list of valid resource paths at the top of this section.
+  * **Code**: `422`; Reason: `Non Integer Value`<br />
+    **Notes**: When setting the status code with a non integer value.
+  * **Code**: `400`; Reason: `Invalid Status Code`<br />
+    **Notes**: When setting a non-supported status code.
   * **Code**: `404`; Reason: `Handler ID Not Found`<br />
     **Notes**: Refers to the handler resource itself.
 * **Sample Call**:<br />