diff --git a/protos/google/cloud/vision/v1/product_search.proto b/protos/google/cloud/vision/v1/product_search.proto
index bede95be..6df694b8 100644
--- a/protos/google/cloud/vision/v1/product_search.proto
+++ b/protos/google/cloud/vision/v1/product_search.proto
@@ -21,6 +21,7 @@ import "google/cloud/vision/v1/geometry.proto";
 import "google/cloud/vision/v1/product_search_service.proto";
 import "google/protobuf/timestamp.proto";
 import "google/api/annotations.proto";
+import "google/api/resource.proto";
 
 option cc_enable_arenas = true;
 option go_package = "google.golang.org/genproto/googleapis/cloud/vision/v1;vision";
@@ -39,7 +40,9 @@ message ProductSearchParams {
   //
   // Format is:
   // `projects/PROJECT_ID/locations/LOC_ID/productSets/PRODUCT_SET_ID`.
-  string product_set = 6;
+  string product_set = 6 [(google.api.resource_reference) = {
+    type: "vision.googleapis.com/ProductSet"
+  }];
 
   // The list of product categories to search in. Currently, we only consider
   // the first category, and either "homegoods-v2", "apparel-v2", "toys-v2",
diff --git a/protos/google/cloud/vision/v1/product_search_service.proto b/protos/google/cloud/vision/v1/product_search_service.proto
index e5b5c5b5..ecfcdf6c 100644
--- a/protos/google/cloud/vision/v1/product_search_service.proto
+++ b/protos/google/cloud/vision/v1/product_search_service.proto
@@ -260,6 +260,7 @@ service ProductSearch {
     option (google.api.http) = {
       get: "/v1/{name=projects/*/locations/*/products/*/referenceImages/*}"
     };
+    option (google.api.method_signature) = "name";
   }
 
   // Adds a Product to the specified ProductSet. If the Product is already
diff --git a/protos/protos.json b/protos/protos.json
index 29fcad7c..28b91718 100644
--- a/protos/protos.json
+++ b/protos/protos.json
@@ -920,7 +920,10 @@
                         },
                         "productSet": {
                           "type": "string",
-                          "id": 6
+                          "id": 6,
+                          "options": {
+                            "(google.api.resource_reference).type": "vision.googleapis.com/ProductSet"
+                          }
                         },
                         "productCategories": {
                           "rule": "repeated",
@@ -1126,7 +1129,8 @@
                           "requestType": "GetReferenceImageRequest",
                           "responseType": "ReferenceImage",
                           "options": {
-                            "(google.api.http).get": "/v1/{name=projects/*/locations/*/products/*/referenceImages/*}"
+                            "(google.api.http).get": "/v1/{name=projects/*/locations/*/products/*/referenceImages/*}",
+                            "(google.api.method_signature)": "name"
                           }
                         },
                         "AddProductToProductSet": {
diff --git a/synth.metadata b/synth.metadata
index afb63a6d..f9e94574 100644
--- a/synth.metadata
+++ b/synth.metadata
@@ -1,19 +1,19 @@
 {
-  "updateTime": "2019-10-01T11:38:30.509743Z",
+  "updateTime": "2019-10-10T11:36:24.226193Z",
   "sources": [
     {
       "generator": {
         "name": "artman",
-        "version": "0.37.1",
-        "dockerImage": "googleapis/artman@sha256:6068f67900a3f0bdece596b97bda8fc70406ca0e137a941f4c81d3217c994a80"
+        "version": "0.38.0",
+        "dockerImage": "googleapis/artman@sha256:0d2f8d429110aeb8d82df6550ef4ede59d40df9062d260a1580fce688b0512bf"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "ce3c574d1266026cebea3a893247790bd68191c2",
-        "internalRef": "272147209"
+        "sha": "10f91fa12f70e8e0209a45fc10807ed1f77c7e4e",
+        "internalRef": "273826591"
       }
     },
     {