diff --git a/google/pubsub/v1/BUILD.bazel b/google/pubsub/v1/BUILD.bazel
index f1512dc6da..78d98d2729 100644
--- a/google/pubsub/v1/BUILD.bazel
+++ b/google/pubsub/v1/BUILD.bazel
@@ -11,7 +11,7 @@ proto_library(
     srcs = ["pubsub.proto"],
     deps = [
         "//google/api:annotations_proto",
-        "//google/api:resource_proto",
+        "//google/api:client_proto",
         "@com_google_protobuf//:duration_proto",
         "@com_google_protobuf//:empty_proto",
         "@com_google_protobuf//:field_mask_proto",
diff --git a/google/pubsub/v1/pubsub.proto b/google/pubsub/v1/pubsub.proto
index 7cea47b1e5..ea0d4c7e53 100644
--- a/google/pubsub/v1/pubsub.proto
+++ b/google/pubsub/v1/pubsub.proto
@@ -18,7 +18,7 @@ syntax = "proto3";
 package google.pubsub.v1;
 
 import "google/api/annotations.proto";
-import "google/api/resource.proto";
+import "google/api/client.proto";
 import "google/protobuf/duration.proto";
 import "google/protobuf/empty.proto";
 import "google/protobuf/field_mask.proto";
@@ -36,6 +36,11 @@ option ruby_package = "Google::Cloud::PubSub::V1";
 // The service that an application uses to manipulate topics, and to send
 // messages to a topic.
 service Publisher {
+  option (google.api.default_host) = "pubsub.googleapis.com";
+  option (google.api.oauth_scopes) =
+      "https://www.googleapis.com/auth/cloud-platform,"
+      "https://www.googleapis.com/auth/pubsub";
+
   // Creates the given topic with the given name. See the
   // <a href="https://cloud.google.com/pubsub/docs/admin#resource_names">
   // resource name rules</a>.
@@ -112,12 +117,11 @@ service Publisher {
 }
 
 message MessageStoragePolicy {
-  // The list of GCP region IDs where messages that are published to the topic
+  // A list of IDs of GCP regions where messages that are published to the topic
   // may be persisted in storage. Messages published by publishers running in
   // non-allowed GCP regions (or running outside of GCP altogether) will be
-  // routed for storage in one of the allowed regions. An empty list indicates a
-  // misconfiguration at the project or organization level, which will result in
-  // all Publish operations failing.
+  // routed for storage in one of the allowed regions. An empty list means that
+  // no regions are allowed, and is not a valid configuration.
   repeated string allowed_persistence_regions = 1;
 }
 
@@ -135,21 +139,15 @@ message Topic {
   // managing labels</a>.
   map<string, string> labels = 2;
 
-  // Policy constraining how messages published to the topic may be stored. It
-  // is determined when the topic is created based on the policy configured at
-  // the project level. It must not be set by the caller in the request to
-  // CreateTopic or to UpdateTopic. This field will be populated in the
-  // responses for GetTopic, CreateTopic, and UpdateTopic: if not present in the
-  // response, then no constraints are in effect.
+  // Policy constraining the set of Google Cloud Platform regions where messages
+  // published to the topic may be stored. If not present, then no constraints
+  // are in effect.
   MessageStoragePolicy message_storage_policy = 3;
 
   // The resource name of the Cloud KMS CryptoKey to be used to protect access
   // to messages published on this topic.
   //
   // The expected format is `projects/*/locations/*/keyRings/*/cryptoKeys/*`.
-  // <b>EXPERIMENTAL:</b> This feature is part of a closed alpha release. This
-  // API might be changed in backward-incompatible ways and is not recommended
-  // for production use. It is not subject to any SLA or deprecation policy.
   string kms_key_name = 5;
 }
 
@@ -316,6 +314,11 @@ message DeleteTopicRequest {
 // consume messages from a subscription via the `Pull` method or by
 // establishing a bi-directional stream using the `StreamingPull` method.
 service Subscriber {
+  option (google.api.default_host) = "pubsub.googleapis.com";
+  option (google.api.oauth_scopes) =
+      "https://www.googleapis.com/auth/cloud-platform,"
+      "https://www.googleapis.com/auth/pubsub";
+
   // Creates a subscription to a given topic. See the
   // <a href="https://cloud.google.com/pubsub/docs/admin#resource_names">
   // resource name rules</a>.
@@ -646,27 +649,27 @@ message PushConfig {
   // For example, a Webhook endpoint might use "https://example.com/push".
   string push_endpoint = 1;
 
-  // Endpoint configuration attributes.
+  // Endpoint configuration attributes that can be used to control different
+  // aspects of the message delivery.
   //
-  // Every endpoint has a set of API supported attributes that can be used to
-  // control different aspects of the message delivery.
-  //
-  // The currently supported attribute is `x-goog-version`, which you can
+  // The only currently supported attribute is `x-goog-version`, which you can
   // use to change the format of the pushed message. This attribute
   // indicates the version of the data expected by the endpoint. This
   // controls the shape of the pushed message (i.e., its fields and metadata).
-  // The endpoint version is based on the version of the Pub/Sub API.
   //
   // If not present during the `CreateSubscription` call, it will default to
-  // the version of the API used to make such call. If not present during a
+  // the version of the Pub/Sub API used to make such call. If not present in a
   // `ModifyPushConfig` call, its value will not be changed. `GetSubscription`
   // calls will always return a valid version, even if the subscription was
   // created without this attribute.
   //
-  // The possible values for this attribute are:
+  // The only supported values for the `x-goog-version` attribute are:
   //
   // * `v1beta1`: uses the push format defined in the v1beta1 Pub/Sub API.
   // * `v1` or `v1beta2`: uses the push format defined in the v1 Pub/Sub API.
+  //
+  // For example:
+  // <pre><code>attributes { "x-goog-version": "v1" } </code></pre>
   map<string, string> attributes = 2;
 
   // An authentication method used by push endpoints to verify the source of