improve comments in math.proto
diff --git a/src/csharp/Grpc.Examples/MathGrpc.cs b/src/csharp/Grpc.Examples/MathGrpc.cs
index 9319e31..4bbefcb 100644
--- a/src/csharp/Grpc.Examples/MathGrpc.cs
+++ b/src/csharp/Grpc.Examples/MathGrpc.cs
@@ -85,8 +85,8 @@
     public abstract class MathBase
     {
       /// <summary>
-      ///  Div divides args.dividend by args.divisor and returns the quotient and
-      ///  remainder.
+      ///  Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+      ///  and remainder.
       /// </summary>
       public virtual global::System.Threading.Tasks.Task<global::Math.DivReply> Div(global::Math.DivArgs request, ServerCallContext context)
       {
@@ -105,7 +105,7 @@
       }
 
       /// <summary>
-      ///  Fib generates numbers in the Fibonacci sequence.  If args.limit > 0, Fib
+      ///  Fib generates numbers in the Fibonacci sequence.  If FibArgs.limit > 0, Fib
       ///  generates up to limit numbers; otherwise it continues until the call is
       ///  canceled.  Unlike Fib above, Fib has no final FibReply.
       /// </summary>
@@ -144,32 +144,32 @@
       }
 
       /// <summary>
-      ///  Div divides args.dividend by args.divisor and returns the quotient and
-      ///  remainder.
+      ///  Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+      ///  and remainder.
       /// </summary>
       public virtual global::Math.DivReply Div(global::Math.DivArgs request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         return Div(request, new CallOptions(headers, deadline, cancellationToken));
       }
       /// <summary>
-      ///  Div divides args.dividend by args.divisor and returns the quotient and
-      ///  remainder.
+      ///  Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+      ///  and remainder.
       /// </summary>
       public virtual global::Math.DivReply Div(global::Math.DivArgs request, CallOptions options)
       {
         return CallInvoker.BlockingUnaryCall(__Method_Div, null, options, request);
       }
       /// <summary>
-      ///  Div divides args.dividend by args.divisor and returns the quotient and
-      ///  remainder.
+      ///  Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+      ///  and remainder.
       /// </summary>
       public virtual AsyncUnaryCall<global::Math.DivReply> DivAsync(global::Math.DivArgs request, Metadata headers = null, DateTime? deadline = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         return DivAsync(request, new CallOptions(headers, deadline, cancellationToken));
       }
       /// <summary>
-      ///  Div divides args.dividend by args.divisor and returns the quotient and
-      ///  remainder.
+      ///  Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+      ///  and remainder.
       /// </summary>
       public virtual AsyncUnaryCall<global::Math.DivReply> DivAsync(global::Math.DivArgs request, CallOptions options)
       {
@@ -196,7 +196,7 @@
         return CallInvoker.AsyncDuplexStreamingCall(__Method_DivMany, null, options);
       }
       /// <summary>
-      ///  Fib generates numbers in the Fibonacci sequence.  If args.limit > 0, Fib
+      ///  Fib generates numbers in the Fibonacci sequence.  If FibArgs.limit > 0, Fib
       ///  generates up to limit numbers; otherwise it continues until the call is
       ///  canceled.  Unlike Fib above, Fib has no final FibReply.
       /// </summary>
@@ -205,7 +205,7 @@
         return Fib(request, new CallOptions(headers, deadline, cancellationToken));
       }
       /// <summary>
-      ///  Fib generates numbers in the Fibonacci sequence.  If args.limit > 0, Fib
+      ///  Fib generates numbers in the Fibonacci sequence.  If FibArgs.limit > 0, Fib
       ///  generates up to limit numbers; otherwise it continues until the call is
       ///  canceled.  Unlike Fib above, Fib has no final FibReply.
       /// </summary>
diff --git a/src/proto/math/math.proto b/src/proto/math/math.proto
index 311e148..269c60b 100644
--- a/src/proto/math/math.proto
+++ b/src/proto/math/math.proto
@@ -55,8 +55,8 @@
 }
 
 service Math {
-  // Div divides args.dividend by args.divisor and returns the quotient and
-  // remainder.
+  // Div divides DivArgs.dividend by DivArgs.divisor and returns the quotient
+  // and remainder.
   rpc Div (DivArgs) returns (DivReply) {
   }
 
@@ -67,7 +67,7 @@
   rpc DivMany (stream DivArgs) returns (stream DivReply) {
   }
 
-  // Fib generates numbers in the Fibonacci sequence.  If args.limit > 0, Fib
+  // Fib generates numbers in the Fibonacci sequence.  If FibArgs.limit > 0, Fib
   // generates up to limit numbers; otherwise it continues until the call is
   // canceled.  Unlike Fib above, Fib has no final FibReply.
   rpc Fib (FibArgs) returns (stream Num) {