docs: clarify usage of compute_alternative_routes in proto comment

Google APIs · copybara-github · commit 5d7f87c599e5 · 2023-03-10T10:29:38.000-08:00
PiperOrigin-RevId: 515674220
diff --git a/google/maps/routing/v2/routes_service.proto b/google/maps/routing/v2/routes_service.proto
@@ -195,7 +195,8 @@ message ComputeRoutesRequest {
       [(google.api.field_behavior) = OPTIONAL];
 
   // Optional. Specifies whether to calculate alternate routes in addition to
-  // the route.
+  // the route. No alternative routes are returned for requests that have
+  // intermediate waypoints.
   bool compute_alternative_routes = 8 [(google.api.field_behavior) = OPTIONAL];
 
   // Optional. A set of conditions to satisfy that affect the way routes are
