diff --git a/src/v1/image_annotator_client.ts b/src/v1/image_annotator_client.ts
index e8e2b8ef..c543a372 100644
--- a/src/v1/image_annotator_client.ts
+++ b/src/v1/image_annotator_client.ts
@@ -47,6 +47,7 @@ const version = require('../../../package.json').version;
 export class ImageAnnotatorClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -58,6 +59,7 @@ export class ImageAnnotatorClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -102,6 +104,9 @@ export class ImageAnnotatorClient {
     const staticMembers = this.constructor as typeof ImageAnnotatorClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -222,6 +227,9 @@ export class ImageAnnotatorClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -250,7 +258,8 @@ export class ImageAnnotatorClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1.ImageAnnotator,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1/product_search_client.ts b/src/v1/product_search_client.ts
index 7362a5fd..3ab1f21a 100644
--- a/src/v1/product_search_client.ts
+++ b/src/v1/product_search_client.ts
@@ -62,6 +62,7 @@ const version = require('../../../package.json').version;
 export class ProductSearchClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -73,6 +74,7 @@ export class ProductSearchClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -117,6 +119,9 @@ export class ProductSearchClient {
     const staticMembers = this.constructor as typeof ProductSearchClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -258,6 +263,9 @@ export class ProductSearchClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -286,7 +294,8 @@ export class ProductSearchClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1.ProductSearch,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p1beta1/image_annotator_client.ts b/src/v1p1beta1/image_annotator_client.ts
index 9c6a1ccf..cbafd0a3 100644
--- a/src/v1p1beta1/image_annotator_client.ts
+++ b/src/v1p1beta1/image_annotator_client.ts
@@ -41,6 +41,7 @@ const version = require('../../../package.json').version;
 export class ImageAnnotatorClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -52,6 +53,7 @@ export class ImageAnnotatorClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   imageAnnotatorStub?: Promise<{[name: string]: Function}>;
 
@@ -94,6 +96,9 @@ export class ImageAnnotatorClient {
     const staticMembers = this.constructor as typeof ImageAnnotatorClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -153,6 +158,9 @@ export class ImageAnnotatorClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -181,7 +189,8 @@ export class ImageAnnotatorClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p1beta1.ImageAnnotator,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p2beta1/image_annotator_client.ts b/src/v1p2beta1/image_annotator_client.ts
index bed840f2..54a0090f 100644
--- a/src/v1p2beta1/image_annotator_client.ts
+++ b/src/v1p2beta1/image_annotator_client.ts
@@ -47,6 +47,7 @@ const version = require('../../../package.json').version;
 export class ImageAnnotatorClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -58,6 +59,7 @@ export class ImageAnnotatorClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   operationsClient: gax.OperationsClient;
   imageAnnotatorStub?: Promise<{[name: string]: Function}>;
@@ -101,6 +103,9 @@ export class ImageAnnotatorClient {
     const staticMembers = this.constructor as typeof ImageAnnotatorClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -191,6 +196,9 @@ export class ImageAnnotatorClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -219,7 +227,8 @@ export class ImageAnnotatorClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p2beta1.ImageAnnotator,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p3beta1/image_annotator_client.ts b/src/v1p3beta1/image_annotator_client.ts
index 25b22473..11b2d0c1 100644
--- a/src/v1p3beta1/image_annotator_client.ts
+++ b/src/v1p3beta1/image_annotator_client.ts
@@ -47,6 +47,7 @@ const version = require('../../../package.json').version;
 export class ImageAnnotatorClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -58,6 +59,7 @@ export class ImageAnnotatorClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -102,6 +104,9 @@ export class ImageAnnotatorClient {
     const staticMembers = this.constructor as typeof ImageAnnotatorClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -207,6 +212,9 @@ export class ImageAnnotatorClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -235,7 +243,8 @@ export class ImageAnnotatorClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p3beta1.ImageAnnotator,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p3beta1/product_search_client.ts b/src/v1p3beta1/product_search_client.ts
index 34f9be8d..787adcc5 100644
--- a/src/v1p3beta1/product_search_client.ts
+++ b/src/v1p3beta1/product_search_client.ts
@@ -62,6 +62,7 @@ const version = require('../../../package.json').version;
 export class ProductSearchClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -73,6 +74,7 @@ export class ProductSearchClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -117,6 +119,9 @@ export class ProductSearchClient {
     const staticMembers = this.constructor as typeof ProductSearchClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -247,6 +252,9 @@ export class ProductSearchClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -275,7 +283,8 @@ export class ProductSearchClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p3beta1.ProductSearch,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p4beta1/image_annotator_client.ts b/src/v1p4beta1/image_annotator_client.ts
index e091415a..8263df36 100644
--- a/src/v1p4beta1/image_annotator_client.ts
+++ b/src/v1p4beta1/image_annotator_client.ts
@@ -47,6 +47,7 @@ const version = require('../../../package.json').version;
 export class ImageAnnotatorClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -58,6 +59,7 @@ export class ImageAnnotatorClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -102,6 +104,9 @@ export class ImageAnnotatorClient {
     const staticMembers = this.constructor as typeof ImageAnnotatorClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -222,6 +227,9 @@ export class ImageAnnotatorClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -250,7 +258,8 @@ export class ImageAnnotatorClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p4beta1.ImageAnnotator,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/src/v1p4beta1/product_search_client.ts b/src/v1p4beta1/product_search_client.ts
index 38e602eb..0bb2d629 100644
--- a/src/v1p4beta1/product_search_client.ts
+++ b/src/v1p4beta1/product_search_client.ts
@@ -66,6 +66,7 @@ const version = require('../../../package.json').version;
 export class ProductSearchClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -77,6 +78,7 @@ export class ProductSearchClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -121,6 +123,9 @@ export class ProductSearchClient {
     const staticMembers = this.constructor as typeof ProductSearchClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -262,6 +267,9 @@ export class ProductSearchClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -290,7 +298,8 @@ export class ProductSearchClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.cloud.vision.v1p4beta1.ProductSearch,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides