diff --git a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcBuilder.cs b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcBuilder.cs
index 13994db34d..5e12b9da62 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcBuilder.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcBuilder.cs
@@ -3,8 +3,14 @@
 
 namespace Microsoft.Extensions.DependencyInjection
 {
+    /// <summary>
+    /// An interface for configuring MVC services.
+    /// </summary>
     public interface IMvcBuilder
     {
+        /// <summary>
+        /// Gets the <see cref="IServiceCollection"/> where MVC services are configured.
+        /// </summary>
         IServiceCollection Services { get; }
     }
 }
diff --git a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcCoreBuilder.cs b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcCoreBuilder.cs
index 02e0751a66..4c621afe1b 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcCoreBuilder.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/IMvcCoreBuilder.cs
@@ -3,8 +3,14 @@
 
 namespace Microsoft.Extensions.DependencyInjection
 {
+    /// <summary>
+    /// An interface for configuring essential MVC services.
+    /// </summary>
     public interface IMvcCoreBuilder
     {
+        /// <summary>
+        /// Gets the <see cref="IServiceCollection"/> where essential MVC services are configured.
+        /// </summary>
         IServiceCollection Services { get; }
     }
 }
diff --git a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs
index 9f01cd034c..b0454b4410 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs
@@ -22,8 +22,16 @@ using Microsoft.Extensions.PlatformAbstractions;
 
 namespace Microsoft.Extensions.DependencyInjection
 {
+    /// <summary>
+    /// Extension methods for setting up essential MVC services in an <see cref="IServiceCollection" />.
+    /// </summary>
     public static class MvcCoreServiceCollectionExtensions
     {
+        /// <summary>
+        /// Adds essential MVC services to the specified <see cref="IServiceCollection" />.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
+        /// <returns>An <see cref="IMvcCoreBuilder"/> that can be used to further configure the MVC services.</returns>
         public static IMvcCoreBuilder AddMvcCore(this IServiceCollection services)
         {
             if (services == null)
@@ -31,9 +39,18 @@ namespace Microsoft.Extensions.DependencyInjection
                 throw new ArgumentNullException(nameof(services));
             }
 
-            return AddMvcCore(services, setupAction: null);
+            ConfigureDefaultServices(services);
+            AddMvcCoreServices(services);
+
+            return new MvcCoreBuilder(services);
         }
 
+        /// <summary>
+        /// Adds essential MVC services to the specified <see cref="IServiceCollection" />.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
+        /// <param name="setupAction">An <see cref="Action{MvcOptions}"/> to configure the provided <see cref="MvcOptions"/>.</param>
+        /// <returns>An <see cref="IMvcCoreBuilder"/> that can be used to further configure the MVC services.</returns>
         public static IMvcCoreBuilder AddMvcCore(
             this IServiceCollection services,
             Action<MvcOptions> setupAction)
@@ -43,16 +60,15 @@ namespace Microsoft.Extensions.DependencyInjection
                 throw new ArgumentNullException(nameof(services));
             }
 
-            ConfigureDefaultServices(services);
-
-            AddMvcCoreServices(services);
-
-            if (setupAction != null)
+            if (setupAction == null)
             {
-                services.Configure(setupAction);
+                throw new ArgumentNullException(nameof(setupAction));
             }
 
-            return new MvcCoreBuilder(services);
+            var builder = services.AddMvcCore();
+            services.Configure(setupAction);
+
+            return builder;
         }
 
         // To enable unit testing
diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcBuilder.cs b/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcBuilder.cs
index ed25f55d29..84cc8468eb 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcBuilder.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcBuilder.cs
@@ -6,8 +6,15 @@ using Microsoft.Extensions.DependencyInjection;
 
 namespace Microsoft.AspNetCore.Mvc.Internal
 {
+    /// <summary>
+    /// Allows fine grained configuration of MVC services.
+    /// </summary>
     public class MvcBuilder : IMvcBuilder
     {
+        /// <summary>
+        /// Initializes a new <see cref="MvcBuilder"/> instance.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
         public MvcBuilder(IServiceCollection services)
         {
             if (services == null)
@@ -18,6 +25,7 @@ namespace Microsoft.AspNetCore.Mvc.Internal
             Services = services;
         }
 
+        /// <inheritdoc />
         public IServiceCollection Services { get; }
     }
 }
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcCoreBuilder.cs b/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcCoreBuilder.cs
index 3cdef79c09..eb64507a4e 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcCoreBuilder.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Internal/MvcCoreBuilder.cs
@@ -6,8 +6,15 @@ using Microsoft.Extensions.DependencyInjection;
 
 namespace Microsoft.AspNetCore.Mvc.Internal
 {
+    /// <summary>
+    /// Allows fine grained configuration of essential MVC services.
+    /// </summary>
     public class MvcCoreBuilder : IMvcCoreBuilder
     {
+        /// <summary>
+        /// Initializes a new instance of <see cref="MvcCoreBuilder"/>.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
         public MvcCoreBuilder(IServiceCollection services)
         {
             if (services == null)
@@ -18,6 +25,7 @@ namespace Microsoft.AspNetCore.Mvc.Internal
             Services = services;
         }
 
+        /// <inheritdoc />
         public IServiceCollection Services { get; }
     }
 }
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Mvc/MvcServiceCollectionExtensions.cs b/src/Microsoft.AspNetCore.Mvc/MvcServiceCollectionExtensions.cs
index 929841b652..36c876bdaa 100644
--- a/src/Microsoft.AspNetCore.Mvc/MvcServiceCollectionExtensions.cs
+++ b/src/Microsoft.AspNetCore.Mvc/MvcServiceCollectionExtensions.cs
@@ -16,7 +16,7 @@ namespace Microsoft.Extensions.DependencyInjection
         /// Adds MVC services to the specified <see cref="IServiceCollection" />.
         /// </summary>
         /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
+        /// <returns>An <see cref="IMvcBuilder"/> that can be used to further configure the MVC services.</returns>
         public static IMvcBuilder AddMvc(this IServiceCollection services)
         {
             if (services == null)
@@ -24,22 +24,6 @@ namespace Microsoft.Extensions.DependencyInjection
                 throw new ArgumentNullException(nameof(services));
             }
 
-            return AddMvc(services, setupAction: null);
-        }
-
-        /// <summary>
-        /// Adds MVC services to the specified <see cref="IServiceCollection" />.
-        /// </summary>
-        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
-        /// <param name="setupAction">An action delegate to configure the provided <see cref="MvcOptions"/>.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        public static IMvcBuilder AddMvc(this IServiceCollection services, Action<MvcOptions> setupAction)
-        {
-            if (services == null)
-            {
-                throw new ArgumentNullException(nameof(services));
-            }
-
             var builder = services.AddMvcCore();
 
             builder.AddApiExplorer();
@@ -60,11 +44,31 @@ namespace Microsoft.Extensions.DependencyInjection
 
             builder.AddCors();
 
-            if (setupAction != null)
+            return new MvcBuilder(builder.Services);
+        }
+
+        /// <summary>
+        /// Adds MVC services to the specified <see cref="IServiceCollection" />.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection" /> to add services to.</param>
+        /// <param name="setupAction">An <see cref="Action{MvcOptions}"/> to configure the provided <see cref="MvcOptions"/>.</param>
+        /// <returns>An <see cref="IMvcBuilder"/> that can be used to further configure the MVC services.</returns>
+        public static IMvcBuilder AddMvc(this IServiceCollection services, Action<MvcOptions> setupAction)
+        {
+            if (services == null)
             {
-                builder.Services.Configure(setupAction);
+                throw new ArgumentNullException(nameof(services));
             }
-            return new MvcBuilder(services);
+
+            if (setupAction == null)
+            {
+                throw new ArgumentNullException(nameof(setupAction));
+            }
+
+            var builder = services.AddMvc();
+            builder.Services.Configure(setupAction);
+
+            return builder;
         }
     }
 }