diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Properties/Resources.Designer.cs b/src/Microsoft.AspNetCore.Mvc.Core/Properties/Resources.Designer.cs
index 95ff1316b4..c9f9d5b058 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Properties/Resources.Designer.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Properties/Resources.Designer.cs
@@ -427,7 +427,7 @@ namespace Microsoft.AspNetCore.Mvc.Core
         }
 
         /// <summary>
-        /// While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'.
+        /// While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'. To use a '[' or ']' as a literal string in a route or within a constraint, use '[[' or ']]' instead.
         /// </summary>
         internal static string AttributeRoute_TokenReplacement_ReplacementValueNotFound
         {
@@ -435,7 +435,7 @@ namespace Microsoft.AspNetCore.Mvc.Core
         }
 
         /// <summary>
-        /// While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'.
+        /// While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'. To use a '[' or ']' as a literal string in a route or within a constraint, use '[[' or ']]' instead.
         /// </summary>
         internal static string FormatAttributeRoute_TokenReplacement_ReplacementValueNotFound(object p0, object p1, object p2)
         {
diff --git a/src/Microsoft.AspNetCore.Mvc.Core/Resources.resx b/src/Microsoft.AspNetCore.Mvc.Core/Resources.resx
index 8a35cabd50..f6236e6e64 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/Resources.resx
+++ b/src/Microsoft.AspNetCore.Mvc.Core/Resources.resx
@@ -1,17 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
 <root>
-  <!-- 
-    Microsoft ResX Schema 
-    
+  <!--
+    Microsoft ResX Schema
+
     Version 2.0
-    
-    The primary goals of this format is to allow a simple XML format 
-    that is mostly human readable. The generation and parsing of the 
-    various data types are done through the TypeConverter classes 
+
+    The primary goals of this format is to allow a simple XML format
+    that is mostly human readable. The generation and parsing of the
+    various data types are done through the TypeConverter classes
     associated with the data types.
-    
+
     Example:
-    
+
     ... ado.net/XML headers & schema ...
     <resheader name="resmimetype">text/microsoft-resx</resheader>
     <resheader name="version">2.0</resheader>
@@ -26,36 +26,36 @@
         <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
         <comment>This is a comment</comment>
     </data>
-                
-    There are any number of "resheader" rows that contain simple 
+
+    There are any number of "resheader" rows that contain simple
     name/value pairs.
-    
-    Each data row contains a name, and value. The row also contains a 
-    type or mimetype. Type corresponds to a .NET class that support 
-    text/value conversion through the TypeConverter architecture. 
-    Classes that don't support this are serialized and stored with the 
+
+    Each data row contains a name, and value. The row also contains a
+    type or mimetype. Type corresponds to a .NET class that support
+    text/value conversion through the TypeConverter architecture.
+    Classes that don't support this are serialized and stored with the
     mimetype set.
-    
-    The mimetype is used for serialized objects, and tells the 
-    ResXResourceReader how to depersist the object. This is currently not 
+
+    The mimetype is used for serialized objects, and tells the
+    ResXResourceReader how to depersist the object. This is currently not
     extensible. For a given mimetype the value must be set accordingly:
-    
-    Note - application/x-microsoft.net.object.binary.base64 is the format 
-    that the ResXResourceWriter will generate, however the reader can 
+
+    Note - application/x-microsoft.net.object.binary.base64 is the format
+    that the ResXResourceWriter will generate, however the reader can
     read any of the formats listed below.
-    
+
     mimetype: application/x-microsoft.net.object.binary.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
             : and then encoded with base64 encoding.
-    
+
     mimetype: application/x-microsoft.net.object.soap.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
             : and then encoded with base64 encoding.
 
     mimetype: application/x-microsoft.net.object.bytearray.base64
-    value   : The object must be serialized into a byte array 
+    value   : The object must be serialized into a byte array
             : using a System.ComponentModel.TypeConverter
             : and then encoded with base64 encoding.
     -->
@@ -199,7 +199,7 @@
     <comment>{1} is the specific error message.</comment>
   </data>
   <data name="AttributeRoute_TokenReplacement_ReplacementValueNotFound" xml:space="preserve">
-    <value>While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'.</value>
+    <value>While processing template '{0}', a replacement value for the token '{1}' could not be found. Available tokens: '{2}'. To use a '[' or ']' as a literal string in a route or within a constraint, use '[[' or ']]' instead.</value>
   </data>
   <data name="AttributeRoute_TokenReplacement_UnclosedToken" xml:space="preserve">
     <value>A replacement token is not closed.</value>
diff --git a/src/Microsoft.AspNetCore.Mvc.RazorPages/Properties/Resources.Designer.cs b/src/Microsoft.AspNetCore.Mvc.RazorPages/Properties/Resources.Designer.cs
index a5637e77f7..4241a5c649 100644
--- a/src/Microsoft.AspNetCore.Mvc.RazorPages/Properties/Resources.Designer.cs
+++ b/src/Microsoft.AspNetCore.Mvc.RazorPages/Properties/Resources.Designer.cs
@@ -19,7 +19,7 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
         }
 
         /// <summary>
-        /// The @page directive for the Razor page at {0} cannot override the relative path prefix.
+        /// The route for the page at '{0}' cannot start with / or ~/. Pages do not support overriding the file path of the page.
         /// </summary>
         internal static string FormatPageActionDescriptorProvider_RouteTemplateCannotBeOverrideable(object p0)
         {
@@ -74,22 +74,6 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             return string.Format(CultureInfo.CurrentCulture, GetString("ActivatedInstance_MustBeAnInstanceOf"), p0, p1);
         }
 
-        /// <summary>
-        /// The Razor page type '{0}' does not have a parameterless constructor.
-        /// </summary>
-        internal static string PageActivator_TypeDoesNotHaveParameterlessConstructor
-        {
-            get { return GetString("PageActivator_TypeDoesNotHaveParameterlessConstructor"); }
-        }
-
-        /// <summary>
-        /// The Razor page type '{0}' does not have a parameterless constructor.
-        /// </summary>
-        internal static string FormatPageActivator_TypeDoesNotHaveParameterlessConstructor(object p0)
-        {
-            return string.Format(CultureInfo.CurrentCulture, GetString("PageActivator_TypeDoesNotHaveParameterlessConstructor"), p0);
-        }
-
         private static string GetString(string name, params string[] formatterNames)
         {
             var value = _resourceManager.GetString(name);
diff --git a/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationModel/AttributeRouteModelTests.cs b/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationModel/AttributeRouteModelTests.cs
index ab1a76ee0b..e3a54e159e 100644
--- a/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationModel/AttributeRouteModelTests.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationModel/AttributeRouteModelTests.cs
@@ -174,11 +174,12 @@ namespace Microsoft.AspNetCore.Mvc.ApplicationModels
             Assert.Equal(expected, ex.Message);
         }
 
-        [Fact]
-        public void ReplaceTokens_UnknownValue()
+        [Theory]
+        [InlineData("[area]/[controller]/[action]/{deptName:regex(^[a-zA-Z]{1}[a-zA-Z0-9_]*$)}", "a-zA-Z")]
+        [InlineData("[area]/[controller]/[action2]", "action2")]
+        public void ReplaceTokens_UnknownValue(string template, string token)
         {
             // Arrange
-            var template = "[area]/[controller]/[action2]";
             var values = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
             {
                 { "area", "Help" },
@@ -187,9 +188,10 @@ namespace Microsoft.AspNetCore.Mvc.ApplicationModels
             };
 
             var expected =
-                "While processing template '[area]/[controller]/[action2]', " +
-                "a replacement value for the token 'action2' could not be found. " +
-                "Available tokens: 'action, area, controller'.";
+                $"While processing template '{template}', " +
+                $"a replacement value for the token '{token}' could not be found. " +
+                "Available tokens: 'action, area, controller'. To use a '[' or ']' as a literal string in a " +
+                "route or within a constraint, use '[[' or ']]' instead.";
 
             // Act
             var ex = Assert.Throws<InvalidOperationException>(
diff --git a/test/Microsoft.AspNetCore.Mvc.Core.Test/Internal/ControllerActionDescriptorProviderTests.cs b/test/Microsoft.AspNetCore.Mvc.Core.Test/Internal/ControllerActionDescriptorProviderTests.cs
index faa86f90b2..5a6302c484 100644
--- a/test/Microsoft.AspNetCore.Mvc.Core.Test/Internal/ControllerActionDescriptorProviderTests.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Core.Test/Internal/ControllerActionDescriptorProviderTests.cs
@@ -444,7 +444,8 @@ namespace Microsoft.AspNetCore.Mvc.Internal
                 "Error 1:" + Environment.NewLine +
                 $"For action: '{controllerTypeInfo.FullName}.Unknown ({assemblyName})'" + Environment.NewLine +
                 "Error: While processing template 'stub/[action]/[unknown]', a replacement value for the token 'unknown' " +
-                "could not be found. Available tokens: 'action, controller'." + Environment.NewLine +
+                "could not be found. Available tokens: 'action, controller'. To use a '[' or ']' as a literal string in" +
+                " a route or within a constraint, use '[[' or ']]' instead." + Environment.NewLine +
                 Environment.NewLine +
                 "Error 2:" + Environment.NewLine +
                 $"For action: '{controllerTypeInfo.FullName}.Invalid ({assemblyName})'" + Environment.NewLine +
@@ -701,7 +702,7 @@ namespace Microsoft.AspNetCore.Mvc.Internal
             VerifyMultiLineError(expectedMessage, exception.Message, unorderedStart: 1, unorderedLineCount: 2);
         }
 
-        // Verify that the expected exception and error message is thrown even when the user builds the model 
+        // Verify that the expected exception and error message is thrown even when the user builds the model
         // incorrectly.
         [Fact]
         public void AttributeRouting_ThrowsIfAttributeRoutedAndNonAttributedActions_OnTheSameMethod_UsingCustomConvention()
@@ -906,7 +907,8 @@ namespace Microsoft.AspNetCore.Mvc.Internal
                 "Error 1:" + Environment.NewLine +
                 $"For action: '{controllerTypeInfo.FullName}.Get ({assemblyName})'" + Environment.NewLine +
                 "Error: While processing template 'Products_[unknown]', a replacement value for the token 'unknown' " +
-                "could not be found. Available tokens: 'action, controller'.";
+                "could not be found. Available tokens: 'action, controller'. To use a '[' or ']' as a literal string" +
+                " in a route or within a constraint, use '[[' or ']]' instead.";
 
             // Act & Assert
             var ex = Assert.Throws<InvalidOperationException>(() => { provider.GetDescriptors(); });