diff --git a/src/protocol/route.ts b/src/protocol/route.ts
index 35f30da5..80b7e475 100644
--- a/src/protocol/route.ts
+++ b/src/protocol/route.ts
@@ -174,3 +174,33 @@ export type SCResponses =
   | SCMultiSearchResponse
   | SCSearchResponse
   | SCThingUpdateResponse;
+
+/**
+ * Associated response for a request
+ */
+export type SCAssociatedResponse<REQUEST> =
+  REQUEST extends SCBookAvailabilityRequest ? SCBookAvailabilityResponse :
+    REQUEST extends SCBulkRequest ? SCBulkResponse :
+      REQUEST extends SCBulkAddRequest ? SCBulkAddResponse :
+        REQUEST extends SCBulkDoneRequest ? SCBulkDoneResponse :
+          REQUEST extends SCFeedbackRequest ? SCFeedbackResponse :
+            REQUEST extends SCIndexRequest ? SCIndexResponse :
+              REQUEST extends SCMultiSearchRequest ? SCMultiSearchResponse :
+                REQUEST extends SCSearchRequest ? SCSearchResponse :
+                  REQUEST extends SCThingUpdateRequest ? SCThingUpdateResponse :
+                    never;
+
+/**
+ * Associated request for a response
+ */
+export type SCAssociatedRequest<RESPONSE> =
+  RESPONSE extends SCBookAvailabilityResponse ? SCBookAvailabilityRequest :
+    RESPONSE extends SCBulkResponse ? SCBulkRequest :
+      RESPONSE extends SCBulkAddResponse ? SCBulkAddRequest :
+        RESPONSE extends SCBulkDoneResponse ? SCBulkDoneRequest :
+          RESPONSE extends SCFeedbackResponse ? SCFeedbackRequest :
+            RESPONSE extends SCIndexResponse ? SCIndexRequest :
+              RESPONSE extends SCMultiSearchResponse ? SCMultiSearchRequest :
+                RESPONSE extends SCSearchResponse ? SCSearchRequest :
+                  RESPONSE extends SCThingUpdateResponse ? SCThingUpdateRequest :
+                    never;