diff --git a/discovery/testing-v1.json b/discovery/testing-v1.json
index 120001c8db..b34e73a9e7 100644
--- a/discovery/testing-v1.json
+++ b/discovery/testing-v1.json
@@ -282,7 +282,7 @@
       }
     }
   },
-  "revision": "20211228",
+  "revision": "20220301",
   "rootUrl": "https://testing.googleapis.com/",
   "schemas": {
     "Account": {
@@ -851,7 +851,7 @@
       "type": "object"
     },
     "Date": {
-      "description": "Represents a whole or partial calendar date, such as a birthday. The time of day and time zone are either specified elsewhere or are insignificant. The date is relative to the Gregorian Calendar. This can represent one of the following: * A full date, with non-zero year, month, and day values * A month and day value, with a zero year, such as an anniversary * A year on its own, with zero month and day values * A year and month value, with a zero day, such as a credit card expiration date Related types are google.type.TimeOfDay and `google.protobuf.Timestamp`.",
+      "description": "Represents a whole or partial calendar date, such as a birthday. The time of day and time zone are either specified elsewhere or are insignificant. The date is relative to the Gregorian Calendar. This can represent one of the following: * A full date, with non-zero year, month, and day values * A month and day, with a zero year (e.g., an anniversary) * A year on its own, with a zero month and a zero day * A year and month, with a zero day (e.g., a credit card expiration date) Related types: * google.type.TimeOfDay * google.type.DateTime * google.protobuf.Timestamp",
       "id": "Date",
       "properties": {
         "day": {
@@ -2141,7 +2141,7 @@
       "type": "object"
     },
     "UniformSharding": {
-      "description": "Uniformly shards test cases given a total number of shards. For Instrumentation test, it will be translated to \"-e numShard\" \"-e shardIndex\" AndroidJUnitRunner arguments. With uniform sharding enabled, specifying these sharding arguments via environment_variables is invalid.",
+      "description": "Uniformly shards test cases given a total number of shards. For Instrumentation test, it will be translated to \"-e numShard\" \"-e shardIndex\" AndroidJUnitRunner arguments. Based on the sharding mechanism AndroidJUnitRunner uses, there is no guarantee that test cases will be distributed uniformly across all shards. With uniform sharding enabled, specifying these sharding arguments via environment_variables is invalid.",
       "id": "UniformSharding",
       "properties": {
         "numShards": {
diff --git a/src/apis/testing/v1.ts b/src/apis/testing/v1.ts
index c31d0732cc..f04ebd24ee 100644
--- a/src/apis/testing/v1.ts
+++ b/src/apis/testing/v1.ts
@@ -518,7 +518,7 @@ export namespace testing_v1 {
     value?: string | null;
   }
   /**
-   * Represents a whole or partial calendar date, such as a birthday. The time of day and time zone are either specified elsewhere or are insignificant. The date is relative to the Gregorian Calendar. This can represent one of the following: * A full date, with non-zero year, month, and day values * A month and day value, with a zero year, such as an anniversary * A year on its own, with zero month and day values * A year and month value, with a zero day, such as a credit card expiration date Related types are google.type.TimeOfDay and `google.protobuf.Timestamp`.
+   * Represents a whole or partial calendar date, such as a birthday. The time of day and time zone are either specified elsewhere or are insignificant. The date is relative to the Gregorian Calendar. This can represent one of the following: * A full date, with non-zero year, month, and day values * A month and day, with a zero year (e.g., an anniversary) * A year on its own, with a zero month and a zero day * A year and month, with a zero day (e.g., a credit card expiration date) Related types: * google.type.TimeOfDay * google.type.DateTime * google.protobuf.Timestamp
    */
   export interface Schema$Date {
     /**
@@ -1410,7 +1410,7 @@ export namespace testing_v1 {
     packetLossRatio?: number | null;
   }
   /**
-   * Uniformly shards test cases given a total number of shards. For Instrumentation test, it will be translated to "-e numShard" "-e shardIndex" AndroidJUnitRunner arguments. With uniform sharding enabled, specifying these sharding arguments via environment_variables is invalid.
+   * Uniformly shards test cases given a total number of shards. For Instrumentation test, it will be translated to "-e numShard" "-e shardIndex" AndroidJUnitRunner arguments. Based on the sharding mechanism AndroidJUnitRunner uses, there is no guarantee that test cases will be distributed uniformly across all shards. With uniform sharding enabled, specifying these sharding arguments via environment_variables is invalid.
    */
   export interface Schema$UniformSharding {
     /**