diff --git a/PowerShellEditorServices.build.ps1 b/PowerShellEditorServices.build.ps1
index 5b99a9fb7..861f5d368 100644
--- a/PowerShellEditorServices.build.ps1
+++ b/PowerShellEditorServices.build.ps1
@@ -18,7 +18,7 @@ if ($PSVersionTable.PSEdition -ne "Core") {
     Add-Type -Assembly System.IO.Compression.FileSystem
 }
 
-task SetupDotNet -Before Restore, Clean, Build, Test, TestPowerShellApi, PackageNuGet {
+task SetupDotNet -Before Restore, Clean, Build, TestHost, TestServer, TestProtocol, TestPowerShellApi, PackageNuGet {
 
     $requiredSdkVersion = "1.0.0"
 
@@ -157,9 +157,17 @@ function UploadTestLogs {
     }
 }
 
-task Test -If { !$script:IsUnix } {
+task Test TestServer,TestProtocol,TestHost
+
+task TestServer -If { !$script:IsUnix } {
     exec { & $script:dotnetExe test -c $Configuration -f net452 .\test\PowerShellEditorServices.Test\PowerShellEditorServices.Test.csproj }
+}
+
+task TestProtocol -If { !$script:IsUnix} {
     exec { & $script:dotnetExe test -c $Configuration -f net452 .\test\PowerShellEditorServices.Test.Protocol\PowerShellEditorServices.Test.Protocol.csproj }
+}
+
+task TestHost -If { !$script:IsUnix} {
     exec { & $script:dotnetExe test -c $Configuration -f net452 .\test\PowerShellEditorServices.Test.Host\PowerShellEditorServices.Test.Host.csproj }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/Client/LanguageClientBase.cs b/src/PowerShellEditorServices.Protocol/Client/LanguageClientBase.cs
index 665383d0d..4cbd62aa0 100644
--- a/src/PowerShellEditorServices.Protocol/Client/LanguageClientBase.cs
+++ b/src/PowerShellEditorServices.Protocol/Client/LanguageClientBase.cs
@@ -34,7 +34,7 @@ protected override Task OnStart()
         protected override async Task OnStop()
         {
             // First, notify the language server that we're stopping
-            var response = await this.SendRequest(ShutdownRequest.Type, new object());
+            var response = await this.SendRequest<object, object, object>(ShutdownRequest.Type);
             await this.SendEvent(ExitNotification.Type, new object());
         }
 
diff --git a/src/PowerShellEditorServices.Protocol/Client/LanguageServiceClient.cs b/src/PowerShellEditorServices.Protocol/Client/LanguageServiceClient.cs
index 67d769ed3..63fde920f 100644
--- a/src/PowerShellEditorServices.Protocol/Client/LanguageServiceClient.cs
+++ b/src/PowerShellEditorServices.Protocol/Client/LanguageServiceClient.cs
@@ -15,7 +15,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.Client
 {
     public class LanguageServiceClient : LanguageClientBase
     {
-        private Dictionary<string, ScriptFileMarker[]> cachedDiagnostics = 
+        private Dictionary<string, ScriptFileMarker[]> cachedDiagnostics =
             new Dictionary<string, ScriptFileMarker[]>();
 
         public LanguageServiceClient(ChannelBase clientChannel)
@@ -34,15 +34,15 @@ protected override Task Initialize()
         protected override Task OnConnect()
         {
             // Send the 'initialize' request and wait for the response
-            var initializeRequest = new InitializeRequest
+            var initializeParams = new InitializeParams
             {
                 RootPath = "",
                 Capabilities = new ClientCapabilities()
             };
 
             return this.SendRequest(
-                InitializeRequest.Type, 
-                initializeRequest);
+                InitializeRequest.Type,
+                initializeParams);
         }
 
         #region Events
@@ -62,7 +62,7 @@ protected void OnDiagnosticsReceived(string filePath)
         #region Private Methods
 
         private Task HandlePublishDiagnosticsEvent(
-            PublishDiagnosticsNotification diagnostics, 
+            PublishDiagnosticsNotification diagnostics,
             EventContext eventContext)
         {
             string normalizedPath = diagnostics.Uri.ToLower();
@@ -79,7 +79,7 @@ private Task HandlePublishDiagnosticsEvent(
 
         private static ScriptFileMarker GetMarkerFromDiagnostic(Diagnostic diagnostic)
         {
-            DiagnosticSeverity severity = 
+            DiagnosticSeverity severity =
                 diagnostic.Severity.GetValueOrDefault(
                     DiagnosticSeverity.Error);
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/AttachRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/AttachRequest.cs
index 4699a4315..e9734e002 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/AttachRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/AttachRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class AttachRequest
     {
         public static readonly
-            RequestType<AttachRequestArguments, object> Type =
-            RequestType<AttachRequestArguments, object>.Create("attach");
+            RequestType<AttachRequestArguments, object, object, object> Type =
+            RequestType<AttachRequestArguments, object, object, object>.Create("attach");
     }
 
     public class AttachRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ConfigurationDoneRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ConfigurationDoneRequest.cs
index ef5e0c8ef..11cbc4ded 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ConfigurationDoneRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ConfigurationDoneRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ConfigurationDoneRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("configurationDone");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("configurationDone");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinueRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinueRequest.cs
index 5ee5b2ec9..3f9dbc59c 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinueRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinueRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ContinueRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("continue");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("continue");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinuedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinuedEvent.cs
index 8e307500a..af442750f 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinuedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ContinuedEvent.cs
@@ -3,6 +3,7 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 //
 
+using System;
 using Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol;
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
@@ -10,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ContinuedEvent
     {
         public static readonly
-            EventType<ContinuedEvent> Type =
-            EventType<ContinuedEvent>.Create("continued");
+            NotificationType<ContinuedEvent, object> Type =
+            NotificationType<ContinuedEvent, object>.Create("continued");
 
         public int ThreadId { get; set; }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/DisconnectRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/DisconnectRequest.cs
index 7f7036b0c..2235206cd 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/DisconnectRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/DisconnectRequest.cs
@@ -7,11 +7,11 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
 {
-    public class DisconnectRequest 
+    public class DisconnectRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("disconnect");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("disconnect");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/EvaluateRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/EvaluateRequest.cs
index b079f59ae..d45e7d44a 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/EvaluateRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/EvaluateRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class EvaluateRequest
     {
         public static readonly
-            RequestType<EvaluateRequestArguments, EvaluateResponseBody> Type =
-            RequestType<EvaluateRequestArguments, EvaluateResponseBody>.Create("evaluate");
+            RequestType<EvaluateRequestArguments, EvaluateResponseBody, object, object> Type =
+            RequestType<EvaluateRequestArguments, EvaluateResponseBody, object, object>.Create("evaluate");
     }
 
     public class EvaluateRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ExitedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ExitedEvent.cs
index 8a2189736..9f1a0d6ce 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ExitedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ExitedEvent.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ExitedEvent
     {
         public static readonly
-            EventType<ExitedEventBody> Type =
-            EventType<ExitedEventBody>.Create("exited");
+            NotificationType<ExitedEventBody, object> Type =
+            NotificationType<ExitedEventBody, object>.Create("exited");
     }
 
     public class ExitedEventBody
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializeRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializeRequest.cs
index 52a8869d3..7904759d9 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializeRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializeRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class InitializeRequest
     {
         public static readonly
-            RequestType<InitializeRequestArguments, InitializeResponseBody> Type =
-            RequestType<InitializeRequestArguments, InitializeResponseBody>.Create("initialize");
+            RequestType<InitializeRequestArguments, InitializeResponseBody, object, object> Type =
+            RequestType<InitializeRequestArguments, InitializeResponseBody, object, object>.Create("initialize");
     }
 
     public class InitializeRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializedEvent.cs
index 68ed66807..7253b7b30 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/InitializedEvent.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class InitializedEvent
     {
         public static readonly
-            EventType<object> Type =
-            EventType<object>.Create("initialized");
+            NotificationType<object, object> Type =
+            NotificationType<object, object>.Create("initialized");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/LaunchRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/LaunchRequest.cs
index b81e56f8d..d0a2435ff 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/LaunchRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/LaunchRequest.cs
@@ -12,8 +12,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class LaunchRequest
     {
         public static readonly
-            RequestType<LaunchRequestArguments, object> Type =
-            RequestType<LaunchRequestArguments, object>.Create("launch");
+            RequestType<LaunchRequestArguments, object, object, object> Type =
+            RequestType<LaunchRequestArguments, object, object, object>.Create("launch");
     }
 
     public class LaunchRequestArguments
@@ -36,7 +36,7 @@ public class LaunchRequestArguments
         public bool NoDebug { get; set; }
 
         /// <summary>
-        /// Gets or sets a boolean value that determines whether to automatically stop 
+        /// Gets or sets a boolean value that determines whether to automatically stop
         /// target after launch. If not specified, target does not stop.
         /// </summary>
         public bool StopOnEntry { get; set; }
@@ -53,7 +53,7 @@ public class LaunchRequestArguments
         public string Cwd { get; set; }
 
         /// <summary>
-        /// Gets or sets the absolute path to the runtime executable to be used. 
+        /// Gets or sets the absolute path to the runtime executable to be used.
         /// Default is the runtime executable on the PATH.
         /// </summary>
         public string RuntimeExecutable { get; set; }
@@ -64,7 +64,7 @@ public class LaunchRequestArguments
         public string[] RuntimeArgs { get; set; }
 
         /// <summary>
-        /// Gets or sets optional environment variables to pass to the debuggee. The string valued 
+        /// Gets or sets optional environment variables to pass to the debuggee. The string valued
         /// properties of the 'environmentVariables' are used as key/value pairs.
         /// </summary>
         public Dictionary<string, string> Env { get; set; }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/NextRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/NextRequest.cs
index 5cb2e6acd..1a254b96f 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/NextRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/NextRequest.cs
@@ -13,8 +13,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class NextRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("next");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("next");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/OutputEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/OutputEvent.cs
index a9cfee8c3..0044855c4 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/OutputEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/OutputEvent.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class OutputEvent
     {
         public static readonly
-            EventType<OutputEventBody> Type =
-            EventType<OutputEventBody>.Create("output");
+            NotificationType<OutputEventBody, object> Type =
+            NotificationType<OutputEventBody, object>.Create("output");
     }
 
     public class OutputEventBody
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/PauseRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/PauseRequest.cs
index 86ceee4f4..6fa67c584 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/PauseRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/PauseRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class PauseRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("pause");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("pause");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ScopesRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ScopesRequest.cs
index 044f5bf73..4905ffdfe 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ScopesRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ScopesRequest.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ScopesRequest
     {
         public static readonly
-            RequestType<ScopesRequestArguments, ScopesResponseBody> Type =
-            RequestType<ScopesRequestArguments, ScopesResponseBody>.Create("scopes");
+            RequestType<ScopesRequestArguments, ScopesResponseBody, object, object> Type =
+            RequestType<ScopesRequestArguments, ScopesResponseBody, object, object>.Create("scopes");
     }
 
     [DebuggerDisplay("FrameId = {FrameId}")]
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetBreakpointsRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetBreakpointsRequest.cs
index 5b0f88bf2..82d41ac53 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetBreakpointsRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetBreakpointsRequest.cs
@@ -16,8 +16,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class SetBreakpointsRequest
     {
         public static readonly
-            RequestType<SetBreakpointsRequestArguments, SetBreakpointsResponseBody> Type =
-            RequestType<SetBreakpointsRequestArguments, SetBreakpointsResponseBody>.Create("setBreakpoints");
+            RequestType<SetBreakpointsRequestArguments, SetBreakpointsResponseBody, object, object> Type =
+            RequestType<SetBreakpointsRequestArguments, SetBreakpointsResponseBody, object, object>.Create("setBreakpoints");
     }
 
     public class SetBreakpointsRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetExceptionBreakpointsRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetExceptionBreakpointsRequest.cs
index a586f27bf..6a7313324 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetExceptionBreakpointsRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetExceptionBreakpointsRequest.cs
@@ -14,8 +14,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class SetExceptionBreakpointsRequest
     {
         public static readonly
-            RequestType<SetExceptionBreakpointsRequestArguments, object> Type =
-            RequestType<SetExceptionBreakpointsRequestArguments, object>.Create("setExceptionBreakpoints");
+            RequestType<SetExceptionBreakpointsRequestArguments, object, object, object> Type =
+            RequestType<SetExceptionBreakpointsRequestArguments, object, object, object>.Create("setExceptionBreakpoints");
     }
 
     /// <summary>
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetFunctionBreakpointsRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetFunctionBreakpointsRequest.cs
index 73b75f82e..6fb951553 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetFunctionBreakpointsRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetFunctionBreakpointsRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class SetFunctionBreakpointsRequest
     {
         public static readonly
-            RequestType<SetFunctionBreakpointsRequestArguments, SetBreakpointsResponseBody> Type =
-            RequestType<SetFunctionBreakpointsRequestArguments, SetBreakpointsResponseBody>.Create("setFunctionBreakpoints");
+            RequestType<SetFunctionBreakpointsRequestArguments, SetBreakpointsResponseBody, object, object> Type =
+            RequestType<SetFunctionBreakpointsRequestArguments, SetBreakpointsResponseBody, object, object>.Create("setFunctionBreakpoints");
     }
 
     public class SetFunctionBreakpointsRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetVariableRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetVariableRequest.cs
index 333327454..47e41cb36 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/SetVariableRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/SetVariableRequest.cs
@@ -15,8 +15,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class SetVariableRequest
     {
         public static readonly
-            RequestType<SetVariableRequestArguments, SetVariableResponseBody> Type =
-            RequestType<SetVariableRequestArguments, SetVariableResponseBody>.Create("setVariable");
+            RequestType<SetVariableRequestArguments, SetVariableResponseBody, object, object> Type =
+            RequestType<SetVariableRequestArguments, SetVariableResponseBody, object, object>.Create("setVariable");
     }
 
     [DebuggerDisplay("VariablesReference = {VariablesReference}")]
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/SourceRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/SourceRequest.cs
index 9d185af23..48a2b0a17 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/SourceRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/SourceRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class SourceRequest
     {
         public static readonly
-            RequestType<SourceRequestArguments, SourceResponseBody> Type =
-            RequestType<SourceRequestArguments, SourceResponseBody>.Create("source");
+            RequestType<SourceRequestArguments, SourceResponseBody, object, object> Type =
+            RequestType<SourceRequestArguments, SourceResponseBody, object, object>.Create("source");
     }
 
     public class SourceRequestArguments
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/StackTraceRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/StackTraceRequest.cs
index 06929ba45..4188dcab6 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/StackTraceRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/StackTraceRequest.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class StackTraceRequest
     {
         public static readonly
-            RequestType<StackTraceRequestArguments, StackTraceResponseBody> Type =
-            RequestType<StackTraceRequestArguments, StackTraceResponseBody>.Create("stackTrace");
+            RequestType<StackTraceRequestArguments, StackTraceResponseBody, object, object> Type =
+            RequestType<StackTraceRequestArguments, StackTraceResponseBody, object, object>.Create("stackTrace");
     }
 
     [DebuggerDisplay("ThreadId = {ThreadId}, Levels = {Levels}")]
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/StartedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/StartedEvent.cs
index f08f504b4..5b32d4a84 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/StartedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/StartedEvent.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class StartedEvent
     {
         public static readonly
-            EventType<object> Type =
-            EventType<object>.Create("started");
+            NotificationType<object, object> Type =
+            NotificationType<object, object>.Create("started");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/StepInRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/StepInRequest.cs
index cfd8f7648..ec825ebbd 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/StepInRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/StepInRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class StepInRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("stepIn");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("stepIn");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/StepOutRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/StepOutRequest.cs
index 5b86f3f7c..be0a31807 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/StepOutRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/StepOutRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class StepOutRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("stepOut");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("stepOut");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/StoppedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/StoppedEvent.cs
index 8d88a1e5a..a3c2a7921 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/StoppedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/StoppedEvent.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class StoppedEvent
     {
         public static readonly
-            EventType<StoppedEventBody> Type =
-            EventType<StoppedEventBody>.Create("stopped");
+            NotificationType<StoppedEventBody, object> Type =
+            NotificationType<StoppedEventBody, object>.Create("stopped");
     }
 
     public class StoppedEventBody
@@ -26,7 +26,7 @@ public class StoppedEventBody
         /// </summary>
         public int? ThreadId { get; set; }
 
-        public Source Source { get; set; } 
+        public Source Source { get; set; }
 
         /// <summary>
         /// Gets or sets additional information such as an error message.
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/TerminatedEvent.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/TerminatedEvent.cs
index 39202676d..514d0bcae 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/TerminatedEvent.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/TerminatedEvent.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class TerminatedEvent
     {
         public static readonly
-            EventType<TerminatedEvent> Type =
-            EventType<TerminatedEvent>.Create("terminated");
+            NotificationType<TerminatedEvent, object> Type =
+            NotificationType<TerminatedEvent, object>.Create("terminated");
 
         public bool Restart { get; set; }
     }
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/ThreadsRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/ThreadsRequest.cs
index e72fcc969..24432d671 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/ThreadsRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/ThreadsRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class ThreadsRequest
     {
         public static readonly
-            RequestType<object, ThreadsResponseBody> Type =
-            RequestType<object, ThreadsResponseBody>.Create("threads");
+            RequestType<object, ThreadsResponseBody, object, object> Type =
+            RequestType<object, ThreadsResponseBody, object, object>.Create("threads");
     }
 
     public class ThreadsResponseBody
diff --git a/src/PowerShellEditorServices.Protocol/DebugAdapter/VariablesRequest.cs b/src/PowerShellEditorServices.Protocol/DebugAdapter/VariablesRequest.cs
index 40dbaabb9..f387c500f 100644
--- a/src/PowerShellEditorServices.Protocol/DebugAdapter/VariablesRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/DebugAdapter/VariablesRequest.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.DebugAdapter
     public class VariablesRequest
     {
         public static readonly
-            RequestType<VariablesRequestArguments, VariablesResponseBody> Type =
-            RequestType<VariablesRequestArguments, VariablesResponseBody>.Create("variables");
+            RequestType<VariablesRequestArguments, VariablesResponseBody, object, object> Type =
+            RequestType<VariablesRequestArguments, VariablesResponseBody, object, object>.Create("variables");
     }
 
     [DebuggerDisplay("VariablesReference = {VariablesReference}")]
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ClientCapabilities.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ClientCapabilities.cs
index 2bebdeb65..f66982c43 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ClientCapabilities.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ClientCapabilities.cs
@@ -18,6 +18,9 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     /// </summary>
     public class ClientCapabilities
     {
+        public WorkspaceClientCapabilities Workspace { get; set; }
+        public TextDocumentClientCapabilities TextDocument { get; set; }
+        public object Experimental { get; set; }
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/CodeAction.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/CodeAction.cs
index deb0cb17f..a382d8dcf 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/CodeAction.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/CodeAction.cs
@@ -6,13 +6,28 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class CodeActionRequest
     {
         public static readonly
-            RequestType<CodeActionRequest, CodeActionCommand[]> Type =
-            RequestType<CodeActionRequest, CodeActionCommand[]>.Create("textDocument/codeAction");
+            RequestType<CodeActionParams, CodeActionCommand[], object, TextDocumentRegistrationOptions> Type =
+            RequestType<CodeActionParams, CodeActionCommand[], object, TextDocumentRegistrationOptions>.Create("textDocument/codeAction");
+    }
 
+    /// <summary>
+    /// Parameters for CodeActionRequest.
+    /// </summary>
+    public class CodeActionParams
+    {
+        /// <summary>
+        /// The document in which the command was invoked.
+        /// </summary>
         public TextDocumentIdentifier TextDocument { get; set; }
 
+        /// <summary>
+        /// The range for which the command was invoked.
+        /// </summary>
         public Range Range { get; set; }
 
+        /// <summary>
+        /// Context carrying additional information.
+        /// </summary>
         public CodeActionContext Context { get; set; }
     }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Completion.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Completion.cs
index 72d4a6ded..38fb9e431 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Completion.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Completion.cs
@@ -11,38 +11,51 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class CompletionRequest
     {
         public static readonly
-            RequestType<TextDocumentPosition, CompletionItem[]> Type =
-            RequestType<TextDocumentPosition, CompletionItem[]>.Create("textDocument/completion");
+            RequestType<TextDocumentPositionParams, CompletionItem[], object, CompletionRegistrationOptions> Type =
+            RequestType<TextDocumentPositionParams, CompletionItem[], object, CompletionRegistrationOptions>.Create("textDocument/completion");
     }
 
     public class CompletionResolveRequest
     {
         public static readonly
-            RequestType<CompletionItem, CompletionItem> Type =
-            RequestType<CompletionItem, CompletionItem>.Create("completionItem/resolve");
+            RequestType<CompletionItem, CompletionItem, object, object> Type =
+            RequestType<CompletionItem, CompletionItem, object, object>.Create("completionItem/resolve");
+    }
+
+    /// <summary>
+    /// Completion registration options.
+    /// </summary>
+    public class CompletionRegistrationOptions : TextDocumentRegistrationOptions
+    {
+        // We duplicate the properties of completionOptions class here because
+        // we cannot derive from two classes. One way to get around this situation
+        // is to use define CompletionOptions as an interface instead of a class.
+        public bool? ResolveProvider { get; set; }
+
+        public string[] TriggerCharacters { get; set; }
     }
 
     public enum CompletionItemKind
     {
-        	Text = 1,
-            Method = 2,
-            Function = 3,
-            Constructor = 4,
-            Field = 5,
-            Variable = 6,
-            Class = 7,
-            Interface = 8,
-            Module = 9,
-            Property = 10,
-            Unit = 11,
-            Value = 12,
-            Enum = 13,
-            Keyword = 14,
-            Snippet = 15,
-            Color = 16,
-            File = 17,
-            Reference = 18,
-            Folder = 19
+        Text = 1,
+        Method = 2,
+        Function = 3,
+        Constructor = 4,
+        Field = 5,
+        Variable = 6,
+        Class = 7,
+        Interface = 8,
+        Module = 9,
+        Property = 10,
+        Unit = 11,
+        Value = 12,
+        Enum = 13,
+        Keyword = 14,
+        Snippet = 15,
+        Color = 16,
+        File = 17,
+        Reference = 18,
+        Folder = 19
     }
 
     [DebuggerDisplay("NewText = {NewText}, Range = {Range.Start.Line}:{Range.Start.Character} - {Range.End.Line}:{Range.End.Character}")]
@@ -73,8 +86,16 @@ public class CompletionItem
 
         public string InsertText { get; set; }
 
+        public Range Range { get; set; }
+
+        public string[] CommitCharacters { get; set; }
+
         public TextEdit TextEdit { get; set; }
 
+        public TextEdit[] AdditionalTextEdits { get; set; }
+
+        public CommandType Command { get; set; }
+
         /// <summary>
         /// Gets or sets a custom data field that allows the server to mark
         /// each completion item with an identifier that will help correlate
@@ -83,5 +104,33 @@ public class CompletionItem
         /// </summary>
         public object Data { get; set; }
     }
+
+    /// <summary>
+    /// Represents a reference to a command. Provides a title which will be used to
+    /// represent a command in the UI and, optionally, an array of arguments which
+    /// will be passed to the command handler function when invoked.
+    ///
+    /// The name of the corresponding type in vscode-languageserver-node is Command
+    /// but since .net does not allow a property name (Command) and its enclosing
+    /// type name to be the same we change its name to CommandType.
+    /// </summary>
+    public class CommandType
+    {
+        /// <summary>
+        /// Title of the command.
+        /// </summary>
+        /// <returns></returns>
+        public string Title { get; set; }
+
+        /// <summary>
+        /// The identifier of the actual command handler.
+        /// </summary>
+        public string Command { get; set; }
+
+        /// <summary>
+        /// Arguments that the command handler should be invoked with.
+        /// </summary>
+        public object[] Arguments { get; set; }
+    }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Configuration.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Configuration.cs
index d4f57781d..a4228ee19 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Configuration.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Configuration.cs
@@ -7,11 +7,11 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
 {
-    public class DidChangeConfigurationNotification<TConfig> 
+    public class DidChangeConfigurationNotification<TConfig>
     {
         public static readonly
-            EventType<DidChangeConfigurationParams<TConfig>> Type =
-            EventType<DidChangeConfigurationParams<TConfig>>.Create("workspace/didChangeConfiguration");
+            NotificationType<DidChangeConfigurationParams<TConfig>, object> Type =
+            NotificationType<DidChangeConfigurationParams<TConfig>, object>.Create("workspace/didChangeConfiguration");
     }
 
     public class DidChangeConfigurationParams<TConfig>
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Definition.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Definition.cs
index 37241dd63..336259ba9 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Definition.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Definition.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class DefinitionRequest
     {
         public static readonly
-            RequestType<TextDocumentPosition, Location[]> Type =
-            RequestType<TextDocumentPosition, Location[]>.Create("textDocument/definition");
+            RequestType<TextDocumentPosition, Location[], object, TextDocumentRegistrationOptions> Type =
+            RequestType<TextDocumentPosition, Location[], object, TextDocumentRegistrationOptions>.Create("textDocument/definition");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Diagnostics.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Diagnostics.cs
index 7aa99a69e..e5e46d45f 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Diagnostics.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Diagnostics.cs
@@ -15,8 +15,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class PublishDiagnosticsNotification
     {
         public static readonly
-            EventType<PublishDiagnosticsNotification> Type = 
-            EventType<PublishDiagnosticsNotification>.Create("textDocument/publishDiagnostics");
+            NotificationType<PublishDiagnosticsNotification, object> Type =
+            NotificationType<PublishDiagnosticsNotification, object>.Create("textDocument/publishDiagnostics");
 
         /// <summary>
         /// Gets or sets the URI for which diagnostic information is reported.
@@ -29,7 +29,7 @@ public static readonly
         public Diagnostic[] Diagnostics { get; set; }
     }
 
-    public enum DiagnosticSeverity 
+    public enum DiagnosticSeverity
     {
         /// <summary>
         /// Indicates that the diagnostic represents an error.
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/DocumentHighlight.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/DocumentHighlight.cs
index c169acc44..cf8196f18 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/DocumentHighlight.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/DocumentHighlight.cs
@@ -7,14 +7,14 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
 {
-    public enum DocumentHighlightKind 
+    public enum DocumentHighlightKind
     {
         Text = 1,
         Read = 2,
         Write = 3
     }
 
-    public class DocumentHighlight 
+    public class DocumentHighlight
     {
 	    public Range Range { get; set; }
 
@@ -24,8 +24,8 @@ public class DocumentHighlight
     public class DocumentHighlightRequest
     {
         public static readonly
-            RequestType<TextDocumentPosition, DocumentHighlight[]> Type =
-            RequestType<TextDocumentPosition, DocumentHighlight[]>.Create("textDocument/documentHighlight");
+            RequestType<TextDocumentPositionParams, DocumentHighlight[], object, TextDocumentRegistrationOptions> Type =
+            RequestType<TextDocumentPositionParams, DocumentHighlight[], object, TextDocumentRegistrationOptions>.Create("textDocument/documentHighlight");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/DynamicRegistrationCapability.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/DynamicRegistrationCapability.cs
new file mode 100644
index 000000000..64d2c35ce
--- /dev/null
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/DynamicRegistrationCapability.cs
@@ -0,0 +1,13 @@
+namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
+{
+    /// <summary>
+    /// Class to represent if a capability supports dynamic registration.
+    /// </summary>
+    public class DynamicRegistrationCapability
+    {
+        /// <summary>
+        /// Whether the capability supports dynamic registration.
+        /// </summary>
+        public bool? DynamicRegistration { get; set; }
+    }
+}
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/EditorCommands.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/EditorCommands.cs
index ee39820bd..04d15c0e9 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/EditorCommands.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/EditorCommands.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class ExtensionCommandAddedNotification
     {
         public static readonly
-            EventType<ExtensionCommandAddedNotification> Type =
-            EventType<ExtensionCommandAddedNotification>.Create("powerShell/extensionCommandAdded");
+            NotificationType<ExtensionCommandAddedNotification, object> Type =
+            NotificationType<ExtensionCommandAddedNotification, object>.Create("powerShell/extensionCommandAdded");
 
         public string Name { get; set; }
 
@@ -21,8 +21,8 @@ public static readonly
     public class ExtensionCommandUpdatedNotification
     {
         public static readonly
-            EventType<ExtensionCommandUpdatedNotification> Type =
-            EventType<ExtensionCommandUpdatedNotification>.Create("powerShell/extensionCommandUpdated");
+            NotificationType<ExtensionCommandUpdatedNotification, object> Type =
+            NotificationType<ExtensionCommandUpdatedNotification, object>.Create("powerShell/extensionCommandUpdated");
 
         public string Name { get; set; }
     }
@@ -30,8 +30,8 @@ public static readonly
     public class ExtensionCommandRemovedNotification
     {
         public static readonly
-            EventType<ExtensionCommandRemovedNotification> Type =
-            EventType<ExtensionCommandRemovedNotification>.Create("powerShell/extensionCommandRemoved");
+            NotificationType<ExtensionCommandRemovedNotification, object> Type =
+            NotificationType<ExtensionCommandRemovedNotification, object>.Create("powerShell/extensionCommandRemoved");
 
         public string Name { get; set; }
     }
@@ -49,8 +49,8 @@ public class ClientEditorContext
     public class InvokeExtensionCommandRequest
     {
         public static readonly
-            RequestType<InvokeExtensionCommandRequest, string> Type =
-            RequestType<InvokeExtensionCommandRequest, string>.Create("powerShell/invokeExtensionCommand");
+            RequestType<InvokeExtensionCommandRequest, string, object, object> Type =
+            RequestType<InvokeExtensionCommandRequest, string, object, object>.Create("powerShell/invokeExtensionCommand");
 
         public string Name { get; set; }
 
@@ -60,8 +60,8 @@ public static readonly
     public class GetEditorContextRequest
     {
         public static readonly
-            RequestType<GetEditorContextRequest, ClientEditorContext> Type =
-            RequestType<GetEditorContextRequest, ClientEditorContext>.Create("editor/getEditorContext");
+            RequestType<GetEditorContextRequest, ClientEditorContext, object, object> Type =
+            RequestType<GetEditorContextRequest, ClientEditorContext, object, object>.Create("editor/getEditorContext");
     }
 
     public enum EditorCommandResponse
@@ -73,8 +73,8 @@ public enum EditorCommandResponse
     public class InsertTextRequest
     {
         public static readonly
-            RequestType<InsertTextRequest, EditorCommandResponse> Type =
-            RequestType<InsertTextRequest, EditorCommandResponse>.Create("editor/insertText");
+            RequestType<InsertTextRequest, EditorCommandResponse, object, object> Type =
+            RequestType<InsertTextRequest, EditorCommandResponse, object, object>.Create("editor/insertText");
 
         public string FilePath { get; set; }
 
@@ -86,8 +86,8 @@ public static readonly
     public class SetSelectionRequest
     {
         public static readonly
-            RequestType<SetSelectionRequest, EditorCommandResponse> Type =
-            RequestType<SetSelectionRequest, EditorCommandResponse>.Create("editor/setSelection");
+            RequestType<SetSelectionRequest, EditorCommandResponse, object, object> Type =
+            RequestType<SetSelectionRequest, EditorCommandResponse, object, object>.Create("editor/setSelection");
 
         public Range SelectionRange { get; set; }
     }
@@ -95,8 +95,8 @@ public static readonly
     public class SetCursorPositionRequest
     {
         public static readonly
-            RequestType<SetCursorPositionRequest, EditorCommandResponse> Type =
-            RequestType<SetCursorPositionRequest, EditorCommandResponse>.Create("editor/setCursorPosition");
+            RequestType<SetCursorPositionRequest, EditorCommandResponse, object, object> Type =
+            RequestType<SetCursorPositionRequest, EditorCommandResponse, object, object>.Create("editor/setCursorPosition");
 
         public Position CursorPosition { get; set; }
     }
@@ -104,43 +104,43 @@ public static readonly
     public class OpenFileRequest
     {
         public static readonly
-            RequestType<string, EditorCommandResponse> Type =
-            RequestType<string, EditorCommandResponse>.Create("editor/openFile");
+            RequestType<string, EditorCommandResponse, object, object> Type =
+            RequestType<string, EditorCommandResponse, object, object>.Create("editor/openFile");
     }
 
     public class CloseFileRequest
     {
         public static readonly
-            RequestType<string, EditorCommandResponse> Type =
-            RequestType<string, EditorCommandResponse>.Create("editor/closeFile");
+            RequestType<string, EditorCommandResponse, object, object> Type =
+            RequestType<string, EditorCommandResponse, object, object>.Create("editor/closeFile");
     }
 
     public class ShowInformationMessageRequest
     {
         public static readonly
-            RequestType<string, EditorCommandResponse> Type =
-            RequestType<string, EditorCommandResponse>.Create("editor/showInformationMessage");
+            RequestType<string, EditorCommandResponse, object, object> Type =
+            RequestType<string, EditorCommandResponse, object, object>.Create("editor/showInformationMessage");
     }
 
     public class ShowWarningMessageRequest
     {
         public static readonly
-            RequestType<string, EditorCommandResponse> Type =
-            RequestType<string, EditorCommandResponse>.Create("editor/showWarningMessage");
+            RequestType<string, EditorCommandResponse, object, object> Type =
+            RequestType<string, EditorCommandResponse, object, object>.Create("editor/showWarningMessage");
     }
 
     public class ShowErrorMessageRequest
     {
         public static readonly
-            RequestType<string, EditorCommandResponse> Type =
-            RequestType<string, EditorCommandResponse>.Create("editor/showErrorMessage");
+            RequestType<string, EditorCommandResponse, object, object> Type =
+            RequestType<string, EditorCommandResponse, object, object>.Create("editor/showErrorMessage");
     }
 
     public class SetStatusBarMessageRequest
     {
         public static readonly
-            RequestType<StatusBarMessageDetails, EditorCommandResponse> Type =
-            RequestType<StatusBarMessageDetails, EditorCommandResponse>.Create("editor/setStatusBarMessage");
+            RequestType<StatusBarMessageDetails, EditorCommandResponse, object, object> Type =
+            RequestType<StatusBarMessageDetails, EditorCommandResponse, object, object>.Create("editor/setStatusBarMessage");
     }
 
     public class StatusBarMessageDetails
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ExpandAliasRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ExpandAliasRequest.cs
index cd79c92f2..d5c2a9bc9 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ExpandAliasRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ExpandAliasRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class ExpandAliasRequest
     {
         public static readonly
-            RequestType<string, string> Type =
-            RequestType<string, string>.Create("powerShell/expandAlias");
+            RequestType<string, string, object, object> Type =
+            RequestType<string, string, object, object>.Create("powerShell/expandAlias");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/FindModuleRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/FindModuleRequest.cs
index 12ac6cf96..fe14fdb65 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/FindModuleRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/FindModuleRequest.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class FindModuleRequest
     {
         public static readonly
-            RequestType<List<PSModuleMessage>, object> Type =
-            RequestType<List<PSModuleMessage>, object>.Create("powerShell/findModule");
+            RequestType<List<PSModuleMessage>, object, object, object> Type =
+            RequestType<List<PSModuleMessage>, object, object, object>.Create("powerShell/findModule");
     }
 
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSHostProcessesRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSHostProcessesRequest.cs
index 59d93ac6c..3c33a61d3 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSHostProcessesRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSHostProcessesRequest.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class GetPSHostProcessesRequest
     {
         public static readonly
-            RequestType<object, GetPSHostProcessesResponse[]> Type =
-                RequestType<object, GetPSHostProcessesResponse[]>.Create("powerShell/getPSHostProcesses");
+            RequestType<object, GetPSHostProcessesResponse[], object, object> Type =
+                RequestType<object, GetPSHostProcessesResponse[], object, object>.Create("powerShell/getPSHostProcesses");
     }
 
     public class GetPSHostProcessesResponse
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSSARulesRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSSARulesRequest.cs
index 617e89c6e..2199558c5 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSSARulesRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/GetPSSARulesRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     class GetPSSARulesRequest
     {
         public static readonly
-            RequestType<string, object> Type =
-            RequestType<string, object>.Create("powerShell/getPSSARules");
+            RequestType<string, object, object, object> Type =
+            RequestType<string, object, object, object>.Create("powerShell/getPSSARules");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Hover.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Hover.cs
index 2af60e515..5a036bd7b 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Hover.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Hover.cs
@@ -29,8 +29,8 @@ public class Hover
     public class HoverRequest
     {
         public static readonly
-            RequestType<TextDocumentPosition, Hover> Type =
-            RequestType<TextDocumentPosition, Hover>.Create("textDocument/hover");
+            RequestType<TextDocumentPositionParams, Hover, object, TextDocumentRegistrationOptions> Type =
+            RequestType<TextDocumentPositionParams, Hover, object, TextDocumentRegistrationOptions>.Create("textDocument/hover");
 
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Initialize.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Initialize.cs
index 40a9d1a23..be73b74a0 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Initialize.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Initialize.cs
@@ -10,20 +10,53 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class InitializeRequest
     {
         public static readonly
-            RequestType<InitializeRequest, InitializeResult> Type =
-            RequestType<InitializeRequest, InitializeResult>.Create("initialize");
+            RequestType<InitializeParams, InitializeResult, InitializeError, object> Type =
+            RequestType<InitializeParams, InitializeResult, InitializeError, object>.Create("initialize");
+   }
 
+    public enum TraceType {
+        Off,
+        Messages,
+        Verbose
+    }
+
+    public class InitializeParams {
         /// <summary>
-        /// Gets or sets the root path of the editor's open workspace.
-        /// If null it is assumed that a file was opened without having
-        /// a workspace open.
+        /// The process Id of the parent process that started the server
+        /// </summary>
+        public int ProcessId { get; set; }
+
+        /// <summary>
+        /// The root path of the workspace. It is null if no folder is open.
+        ///
+        /// This property has been deprecated in favor of RootUri.
         /// </summary>
         public string RootPath { get; set; }
 
         /// <summary>
-        /// Gets or sets the capabilities provided by the client (editor).
+        /// The root uri of the workspace. It is null if not folder is open. If both
+        /// `RootUri` and `RootPath` are non-null, `RootUri` should be used.
+        /// </summary>
+        public string RootUri { get; set; }
+
+        /// <summary>
+        /// The capabilities provided by the client.
         /// </summary>
         public ClientCapabilities Capabilities { get; set; }
+
+        /// <summary>
+        /// User provided initialization options.
+        ///
+        /// This is defined as `any` type on the client side.
+        /// </summary>
+        public object InitializeOptions { get; set; }
+
+        // TODO We need to verify if the deserializer will map the type defined in the client
+        // to an enum.
+        /// <summary>
+        /// The initial trace setting. If omitted trace is disabled.
+        /// </summary>
+        public TraceType Trace { get; set; } = TraceType.Off;
     }
 
     public class InitializeResult
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/InstallModuleRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/InstallModuleRequest.cs
index 2be47ce90..096d0e461 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/InstallModuleRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/InstallModuleRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     class InstallModuleRequest
     {
         public static readonly
-            RequestType<string, object> Type =
-            RequestType<string, object>.Create("powerShell/installModule");
+            RequestType<string, object, object, object> Type =
+            RequestType<string, object, object, object>.Create("powerShell/installModule");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/PowerShellVersionRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/PowerShellVersionRequest.cs
index 87a7ac20e..8f16b0abb 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/PowerShellVersionRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/PowerShellVersionRequest.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class PowerShellVersionRequest
     {
         public static readonly
-            RequestType<object, PowerShellVersion> Type =
-            RequestType<object, PowerShellVersion>.Create("powerShell/getVersion");
+            RequestType<object, PowerShellVersion, object, object> Type =
+            RequestType<object, PowerShellVersion, object, object>.Create("powerShell/getVersion");
     }
 
     public class PowerShellVersion
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ProjectTemplate.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ProjectTemplate.cs
index 74878cd43..1b7441b28 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ProjectTemplate.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ProjectTemplate.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class NewProjectFromTemplateRequest
     {
         public static readonly
-            RequestType<NewProjectFromTemplateRequest, NewProjectFromTemplateResponse> Type =
-            RequestType<NewProjectFromTemplateRequest, NewProjectFromTemplateResponse>.Create("powerShell/newProjectFromTemplate");
+            RequestType<NewProjectFromTemplateRequest, NewProjectFromTemplateResponse, object, object> Type =
+            RequestType<NewProjectFromTemplateRequest, NewProjectFromTemplateResponse, object, object>.Create("powerShell/newProjectFromTemplate");
 
         public string DestinationPath { get; set; }
 
@@ -27,8 +27,8 @@ public class NewProjectFromTemplateResponse
     public class GetProjectTemplatesRequest
     {
         public static readonly
-            RequestType<GetProjectTemplatesRequest, GetProjectTemplatesResponse> Type =
-            RequestType<GetProjectTemplatesRequest, GetProjectTemplatesResponse>.Create("powerShell/getProjectTemplates");
+            RequestType<GetProjectTemplatesRequest, GetProjectTemplatesResponse, object, object> Type =
+            RequestType<GetProjectTemplatesRequest, GetProjectTemplatesResponse, object, object>.Create("powerShell/getProjectTemplates");
 
         public bool IncludeInstalledModules { get; set; }
     }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/References.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/References.cs
index a55ebebf9..992464140 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/References.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/References.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class ReferencesRequest
     {
         public static readonly
-            RequestType<ReferencesParams, Location[]> Type =
-            RequestType<ReferencesParams, Location[]>.Create("textDocument/references");
+            RequestType<ReferencesParams, Location[], object, TextDocumentRegistrationOptions> Type =
+            RequestType<ReferencesParams, Location[], object, TextDocumentRegistrationOptions>.Create("textDocument/references");
     }
 
     public class ReferencesParams : TextDocumentPosition
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/RunspaceChanged.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/RunspaceChanged.cs
index 77a0148dc..3f2448097 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/RunspaceChanged.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/RunspaceChanged.cs
@@ -11,8 +11,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class RunspaceChangedEvent
     {
         public static readonly
-            EventType<RunspaceDetails> Type =
-            EventType<RunspaceDetails>.Create("powerShell/runspaceChanged");
+            NotificationType<RunspaceDetails, object> Type =
+            NotificationType<RunspaceDetails, object>.Create("powerShell/runspaceChanged");
     }
 
     public class RunspaceDetails
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptFileMarkersRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptFileMarkersRequest.cs
index 868f53ead..5394ddd4c 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptFileMarkersRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptFileMarkersRequest.cs
@@ -15,8 +15,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     class ScriptFileMarkersRequest
     {
         public static readonly
-            RequestType<ScriptFileMarkerRequestParams, ScriptFileMarkerRequestResultParams> Type =
-                RequestType<ScriptFileMarkerRequestParams, ScriptFileMarkerRequestResultParams>.Create("powerShell/getScriptFileMarkers");
+            RequestType<ScriptFileMarkerRequestParams, ScriptFileMarkerRequestResultParams, object, object> Type =
+                RequestType<ScriptFileMarkerRequestParams, ScriptFileMarkerRequestResultParams, object, object>.Create("powerShell/getScriptFileMarkers");
     }
 
     /// <summary>
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptRegionRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptRegionRequest.cs
index 82791ec54..79b36161e 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptRegionRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ScriptRegionRequest.cs
@@ -13,8 +13,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     class ScriptRegionRequest
     {
         public static readonly
-            RequestType<ScriptRegionRequestParams, ScriptRegionRequestResult> Type =
-                RequestType<ScriptRegionRequestParams, ScriptRegionRequestResult>.Create("powerShell/getScriptRegion");
+            RequestType<ScriptRegionRequestParams, ScriptRegionRequestResult, object, object> Type =
+                RequestType<ScriptRegionRequestParams, ScriptRegionRequestResult, object, object>.Create("powerShell/getScriptRegion");
     }
 
     /// <summary>
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ServerCapabilities.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ServerCapabilities.cs
index aeebb411d..26fec4ae1 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ServerCapabilities.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ServerCapabilities.cs
@@ -26,6 +26,60 @@ public class ServerCapabilities
         public bool? WorkspaceSymbolProvider { get; set; }
 
         public bool? CodeActionProvider { get; set; }
+
+        public bool? CodeLensProvider { get; set; }
+
+        public bool? DocumentFormattingProvider { get; set; }
+
+        public bool? DocumentRangeFormattingProvider { get; set; }
+
+        public DocumentOnTypeFormattingOptions DocumentOnTypeFormattingProvider { get; set; }
+
+        public bool? RenameProvider { get; set; }
+
+        public DocumentLinkOptions DocumentLinkProvider { get; set; }
+
+        public ExecuteCommandOptions ExecuteCommandProvider { get; set; }
+
+        public object Experimental { get; set; }
+    }
+
+    /// <summary>
+    /// Execute command options.
+    /// </summary>
+    public class ExecuteCommandOptions
+    {
+        /// <summary>
+        /// The commands to be executed on the server.
+        /// </summary>
+        public string[] Commands { get; set; }
+    }
+
+    /// <summary>
+    /// Document link options.
+    /// </summary>
+    public class DocumentLinkOptions
+    {
+        /// <summary>
+        /// Document links have a resolve provider.
+        /// </summary>
+        public bool? ResolveProvider { get; set; }
+    }
+
+    /// <summary>
+    /// Options that the server provides for OnTypeFormatting request.
+    /// </summary>
+    public class DocumentOnTypeFormattingOptions
+    {
+        /// <summary>
+        /// A character on which formatting should be triggered.
+        /// </summary>
+        public string FirstTriggerCharacter { get; set; }
+
+        /// <summary>
+        /// More trigger characters.
+        /// </summary>
+        public string[] MoreTriggerCharacters { get; set; }
     }
 
     /// <summary>
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/SetPSSARulesRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/SetPSSARulesRequest.cs
index 49723f708..e3298cbd8 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/SetPSSARulesRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/SetPSSARulesRequest.cs
@@ -10,7 +10,7 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     class SetPSSARulesRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("powerShell/setPSSARules");
+            RequestType<object, object, object, object> Type =
+            RequestType<object, object, object, object>.Create("powerShell/setPSSARules");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/ShowOnlineHelpRequest.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/ShowOnlineHelpRequest.cs
index 49c571faf..1e65df93d 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/ShowOnlineHelpRequest.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/ShowOnlineHelpRequest.cs
@@ -9,8 +9,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
 {
     public class ShowOnlineHelpRequest
     {
-        public static readonly 
-            RequestType<string, object> Type = 
-            RequestType<string, object>.Create("powerShell/showOnlineHelp");
+        public static readonly
+            RequestType<string, object, object, object> Type =
+            RequestType<string, object, object, object>.Create("powerShell/showOnlineHelp");
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/Shutdown.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/Shutdown.cs
index 519719015..f5fffce1c 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/Shutdown.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/Shutdown.cs
@@ -14,8 +14,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class ShutdownRequest
     {
         public static readonly
-            RequestType<object, object> Type =
-            RequestType<object, object>.Create("shutdown");
+            RequestType0<object, object, object> Type =
+            RequestType0<object, object, object>.Create("shutdown");
     }
 
     /// <summary>
@@ -25,8 +25,8 @@ public static readonly
     public class ExitNotification
     {
         public static readonly
-            EventType<object> Type =
-            EventType<object>.Create("exit");
+            NotificationType<object, object> Type =
+            NotificationType<object, object>.Create("exit");
     }
 }
 
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/SignatureHelp.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/SignatureHelp.cs
index 6387461dc..e24fa6358 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/SignatureHelp.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/SignatureHelp.cs
@@ -10,8 +10,16 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
     public class SignatureHelpRequest
     {
         public static readonly
-            RequestType<TextDocumentPosition, SignatureHelp> Type =
-            RequestType<TextDocumentPosition, SignatureHelp>.Create("textDocument/signatureHelp");
+            RequestType<TextDocumentPositionParams, SignatureHelp, object, SignatureHelpRegistrationOptions> Type =
+            RequestType<TextDocumentPositionParams, SignatureHelp, object, SignatureHelpRegistrationOptions>.Create("textDocument/signatureHelp");
+    }
+
+    public class SignatureHelpRegistrationOptions : TextDocumentRegistrationOptions
+    {
+        // We duplicate the properties of SignatureHelpOptions class here because
+        // we cannot derive from two classes. One way to get around this situation
+        // is to use define SignatureHelpOptions as an interface instead of a class.
+        public string[] TriggerCharacters { get; set; }
     }
 
     public class ParameterInformation
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocument.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocument.cs
index 92d516817..8920ef1c4 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocument.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocument.cs
@@ -8,6 +8,39 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
 {
+
+    /// <summary>
+    /// An item to transfer a text document from the client to the server
+    /// </summary>
+    [DebuggerDisplay("TextDocumentItem = {Uri}:{LanguageId}:{Version}:{Text}")]
+    public class TextDocumentItem
+    {
+        /// <summary>
+        /// Gets or sets the URI which identifies the path of the
+        /// text document.
+        /// </summary>
+        public string Uri { get; set; }
+
+        /// <summary>
+        /// The text document's language identifier.
+        /// </summary>
+        /// <returns></returns>
+        public string LanguageId { get; set; }
+
+        /// <summary>
+        /// The version number of this document, which will strictly increase after each change, including
+        /// undo/redo.
+        /// </summary>
+        /// <returns></returns>
+        public int Version { get; set; }
+
+        /// <summary>
+        /// The content of the opened text document.
+        /// </summary>
+        /// <returns></returns>
+        public string Text { get; set; }
+    }
+
     /// <summary>
     /// Defines a base parameter class for identifying a text document.
     /// </summary>
@@ -21,6 +54,17 @@ public class TextDocumentIdentifier
         public string Uri { get; set; }
     }
 
+    /// <summary>
+    /// An identifier to denote a specific version of a text document.
+    /// </summary>
+    public class VersionedTextDocumentIdentifier : TextDocumentIdentifier
+    {
+        /// <summary>
+        /// The version number of this document.
+        /// </summary>
+        public int Version { get; set; }
+    }
+
     /// <summary>
     /// Defines a position in a text document.
     /// </summary>
@@ -33,46 +77,166 @@ public class TextDocumentPosition : TextDocumentIdentifier
         public Position Position { get; set; }
     }
 
-    public class DidOpenTextDocumentNotification : TextDocumentIdentifier
+    /// <summary>
+    /// A parameter literal used in requests to pass a text document and a position inside that document.
+    /// </summary>
+    public class TextDocumentPositionParams
+    {
+        /// <summary>
+        /// The text document.
+        /// </summary>
+        /// <returns></returns>
+        public TextDocumentIdentifier TextDocument { get; set; }
+
+        /// <summary>
+        /// The position inside the text document.
+        /// </summary>
+        /// <returns></returns>
+        public Position Position { get; set; }
+    }
+
+    public class DidOpenTextDocumentNotification
     {
         public static readonly
-            EventType<DidOpenTextDocumentNotification> Type =
-            EventType<DidOpenTextDocumentNotification>.Create("textDocument/didOpen");
+            NotificationType<DidOpenTextDocumentParams, TextDocumentRegistrationOptions> Type =
+            NotificationType<DidOpenTextDocumentParams, TextDocumentRegistrationOptions>.Create("textDocument/didOpen");
+    }
 
+    /// <summary>
+    /// The parameters sent in an open text document notification
+    /// </summary>
+    public class DidOpenTextDocumentParams
+    {
         /// <summary>
-        /// Gets or sets the full content of the opened document.
+        /// The document that was opened.
         /// </summary>
-        public string Text { get; set; }
+        public TextDocumentItem TextDocument { get; set; }
+    }
+
+    /// <summary>
+    /// General text document registration options.
+    /// </summary>
+    public class TextDocumentRegistrationOptions {
+        /// <summary>
+        /// A document selector to identify the scope of the registration. If set to null the document
+        /// selector provided on the client side will be used.
+        /// </summary>
+        public DocumentFilter[] DocumentSelector { get; set; }
+    }
+
+    /// <summary>
+    /// A document filter denotes a document by different properties like the language, the scheme
+    /// of its resource, or a glob-pattern that is applied to the path.
+    /// </summary>
+    public class DocumentFilter
+    {
+        /// <summary>
+        /// A language id, like `powershell`
+        /// </summary>
+        public string Language { get; set; }
+
+        /// <summary>
+        /// A Uri, like `file` or `untitled`
+        /// </summary>
+        public string Scheme { get; set; }
+
+        /// <summary>
+        /// A glob pattern, like `*.{ps1,psd1}`
+        /// </summary>
+        public string Pattern { get; set; }
     }
 
     public class DidCloseTextDocumentNotification
     {
         public static readonly
-            EventType<TextDocumentIdentifier> Type =
-            EventType<TextDocumentIdentifier>.Create("textDocument/didClose");
+            NotificationType<DidCloseTextDocumentParams, TextDocumentRegistrationOptions> Type =
+            NotificationType<DidCloseTextDocumentParams, TextDocumentRegistrationOptions>.Create("textDocument/didClose");
+    }
+
+    /// <summary>
+    /// The parameters sent in a close text document notification.
+    /// </summary>
+    public class DidCloseTextDocumentParams
+    {
+        /// <summary>
+        /// The document that was closed.
+        /// </summary>
+        public TextDocumentIdentifier TextDocument { get; set; }
     }
 
     public class DidSaveTextDocumentNotification
     {
         public static readonly
-            EventType<DidSaveTextDocumentParams> Type =
-            EventType<DidSaveTextDocumentParams>.Create("textDocument/didSave");
+            NotificationType<DidSaveTextDocumentParams, TextDocumentSaveRegistrationOptions> Type =
+            NotificationType<DidSaveTextDocumentParams, TextDocumentSaveRegistrationOptions>.Create("textDocument/didSave");
+    }
+
+    /// <summary>
+    /// Save options.
+    /// </summary>
+    public class SaveOptions {
+        /// <summary>
+        /// The client is supposed to include the content on save.
+        /// </summary>
+        public bool? IncludeText { get; set; }
     }
 
+    public class TextDocumentSaveRegistrationOptions : TextDocumentRegistrationOptions
+    {
+        // We cannot inherit from two base classes (SaveOptions and TextDocumentRegistrationOptions)
+        // simultaneously, hence we repeat this IncludeText flag here.
+        /// <summary>
+        /// The client is supposed to include the content on save.
+        /// </summary>
+        public bool? IncludeText { get; set; }
+    }
+
+    /// <summary>
+    /// The parameters sent in a save text document notification.
+    /// </summary>
     public class DidSaveTextDocumentParams
     {
-        public TextDocumentIdentifier TextDocument { get; set; }
+        /// <summary>
+        /// The document that was saved.
+        /// </summary>
+        public VersionedTextDocumentIdentifier TextDocument { get; set; }
+
+        /// <summary>
+        /// Optional content when saved. Depends on the includeText value when the save notification was
+        /// included.
+        /// </summary>
+        public string Text { get; set; }
     }
 
     public class DidChangeTextDocumentNotification
     {
         public static readonly
-            EventType<DidChangeTextDocumentParams> Type =
-            EventType<DidChangeTextDocumentParams>.Create("textDocument/didChange");
+            NotificationType<DidChangeTextDocumentParams, TextDocumentChangeRegistrationOptions> Type =
+            NotificationType<DidChangeTextDocumentParams, TextDocumentChangeRegistrationOptions>.Create("textDocument/didChange");
     }
 
-    public class DidChangeTextDocumentParams : TextDocumentIdentifier
+    /// <summary>
+    /// Describe options to be used when registered for text document change events.
+    /// </summary>
+    public class TextDocumentChangeRegistrationOptions : TextDocumentRegistrationOptions
     {
+        /// <summary>
+        /// How documents are synced to the server.
+        /// </summary>
+        public TextDocumentSyncKind SyncKind { get; set; }
+    }
+
+    /// <summary>
+    /// The change text document notification's paramters.
+    /// </summary>
+    public class DidChangeTextDocumentParams
+    {
+        /// <summary>
+        /// The document that did change. The version number points to the version after
+        /// all provided content changes have been applied.
+        /// </summary>
+        public VersionedTextDocumentIdentifier TextDocument;
+
         /// <summary>
         /// Gets or sets the list of changes to the document content.
         /// </summary>
@@ -89,7 +253,7 @@ public class TextDocumentChangeEvent
 
         /// <summary>
         /// Gets or sets the length of the Range being replaced in the
-        /// document.  Will be null if the server's TextDocumentSyncKind is 
+        /// document.  Will be null if the server's TextDocumentSyncKind is
         /// Full.
         /// </summary>
         public int? RangeLength { get; set; }
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocumentClientCapabilities.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocumentClientCapabilities.cs
new file mode 100644
index 000000000..c620ad056
--- /dev/null
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/TextDocumentClientCapabilities.cs
@@ -0,0 +1,130 @@
+namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
+{
+    public class TextDocumentClientCapabilities
+    {
+        /// <summary>
+        /// Synchronization capabilities the client supports.
+        /// </summary>
+        public SynchronizationCapabilities Synchronization { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to `textDocument/completion`.
+        /// </summary>
+        public CompletionCapabilities Completion { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/hover`.
+        /// </summary>
+        public DynamicRegistrationCapability Hover { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/signatureHelp`.
+        /// </summary>
+        public DynamicRegistrationCapability SignatureHelp { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/references`.
+        /// </summary>
+        public DynamicRegistrationCapability References { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/documentHighlight`.
+        /// </summary>
+        public DynamicRegistrationCapability DocumentHighlight { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/documentSymbol`.
+        /// </summary>
+        public DynamicRegistrationCapability DocumentSymbol { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/formatting`.
+        /// </summary>
+        public DynamicRegistrationCapability Formatting { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/rangeFormatting`.
+        /// </summary>
+        public DynamicRegistrationCapability RangeFormatting { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/onTypeFormatting`.
+        /// </summary>
+        public DynamicRegistrationCapability OnTypeFormatting { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/definition`.
+        /// </summary>
+        public DynamicRegistrationCapability Definition { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/codeAction`.
+        /// </summary>
+        public DynamicRegistrationCapability CodeAction { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/codeLens`.
+        /// </summary>
+        public DynamicRegistrationCapability CodeLens { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/documentLink`.
+        /// </summary>
+        public DynamicRegistrationCapability DocumentLink { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `textDocument/rename`.
+        /// </summary>
+        public DynamicRegistrationCapability Rename { get; set; }
+    }
+
+    /// <summary>
+    /// Class to represent capabilities specific to `textDocument/completion`.
+    /// </summary>
+    public class CompletionCapabilities : DynamicRegistrationCapability
+    {
+        /// <summary>
+        /// The client supports the following `CompletionItem` specific capabilities.
+        /// </summary>
+        /// <returns></returns>
+        public CompletionItemCapabilities CompletionItem { get; set; }
+    }
+
+    /// <summary>
+    /// Class to represent capabilities specific to `CompletionItem`.
+    /// </summary>
+    public class CompletionItemCapabilities
+    {
+        /// <summary>
+        /// Client supports snippets as insert text.
+        ///
+        /// A snippet can define tab stops and placeholders with `$1`, `$2`
+        /// and `${3:foo}`. `$0` defines the final tab stop, it defaults to
+        /// the end of the snippet. Placeholders with equal identifiers are linked,
+        /// that is typing in one will update others too.
+        /// </summary>
+        public bool? SnippetSupport { get; set; }
+    }
+
+    /// <summary>
+    /// Class to represent synchronization capabilities the client supports.
+    /// </summary>
+    public class SynchronizationCapabilities : DynamicRegistrationCapability
+    {
+        /// <summary>
+        /// The client supports sending will save notifications.
+        /// </summary>
+        public bool? WillSave { get; set; }
+
+        /// <summary>
+        /// The client supports sending a will save request and waits for a response
+        /// providing text edits which will be applied to the document before it is save.
+        /// </summary>
+        public bool? WillSaveWaitUntil { get; set; }
+
+        /// <summary>
+        /// The client supports did save notifications.
+        /// </summary>
+        public bool? DidSave { get; set; }
+    }
+}
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceClientCapabilities.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceClientCapabilities.cs
new file mode 100644
index 000000000..3e781a217
--- /dev/null
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceClientCapabilities.cs
@@ -0,0 +1,47 @@
+namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
+{
+    public class WorkspaceClientCapabilities
+    {
+        /// <summary>
+        /// The client supports applying batch edits to the workspace by
+        /// by supporting the request `workspace/applyEdit'
+        /// /// </summary>
+        bool? ApplyEdit { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to `WorkspaceEdit`.
+        /// </summary>
+        public WorkspaceEditCapabilities WorkspaceEdit { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `workspace/didChangeConfiguration` notification.
+        /// </summary>
+        public DynamicRegistrationCapability DidChangeConfiguration { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `workspace/didChangeWatchedFiles` notification.
+        /// </summary>
+        public DynamicRegistrationCapability DidChangeWatchedFiles { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `workspace/symbol` request.
+        /// </summary>
+        public DynamicRegistrationCapability Symbol { get; set; }
+
+        /// <summary>
+        /// Capabilities specific to the `workspace/executeCommand` request.
+        /// </summary>
+        public DynamicRegistrationCapability ExecuteCommand { get; set; }
+    }
+
+    /// <summary>
+    /// Class to represent capabilities specific to `WorkspaceEdit`.
+    /// </summary>
+    public class WorkspaceEditCapabilities
+    {
+        /// <summary>
+        /// The client supports versioned document changes in `WorkspaceEdit`
+        /// </summary>
+        bool? DocumentChanges { get; set; }
+    }
+}
diff --git a/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceSymbols.cs b/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceSymbols.cs
index 405d6e98e..97e990345 100644
--- a/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceSymbols.cs
+++ b/src/PowerShellEditorServices.Protocol/LanguageServer/WorkspaceSymbols.cs
@@ -7,7 +7,7 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.LanguageServer
 {
-    public enum SymbolKind 
+    public enum SymbolKind
     {
         File = 1,
         Module = 2,
@@ -29,7 +29,7 @@ public enum SymbolKind
         Array = 18,
     }
 
-    public class SymbolInformation 
+    public class SymbolInformation
     {
         public string Name { get; set; }
 
@@ -43,15 +43,26 @@ public class SymbolInformation
     public class DocumentSymbolRequest
     {
         public static readonly
-            RequestType<TextDocumentIdentifier, SymbolInformation[]> Type =
-            RequestType<TextDocumentIdentifier, SymbolInformation[]>.Create("textDocument/documentSymbol");
+            RequestType<DocumentSymbolParams, SymbolInformation[], object, TextDocumentRegistrationOptions> Type =
+            RequestType<DocumentSymbolParams, SymbolInformation[], object, TextDocumentRegistrationOptions>.Create("textDocument/documentSymbol");
+    }
+
+    /// <summary>
+    /// Parameters for a DocumentSymbolRequest
+    /// </summary>
+    public class DocumentSymbolParams
+    {
+        /// <summary>
+        /// The text document.
+        /// </summary>
+        public TextDocumentIdentifier TextDocument { get; set; }
     }
 
     public class WorkspaceSymbolRequest
     {
         public static readonly
-            RequestType<WorkspaceSymbolParams, SymbolInformation[]> Type =
-            RequestType<WorkspaceSymbolParams, SymbolInformation[]>.Create("workspace/symbol");
+            RequestType<WorkspaceSymbolParams, SymbolInformation[], object, object> Type =
+            RequestType<WorkspaceSymbolParams, SymbolInformation[], object, object>.Create("workspace/symbol");
     }
 
     public class WorkspaceSymbolParams
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/AbstractMessageType.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/AbstractMessageType.cs
new file mode 100644
index 000000000..1b2fc37f9
--- /dev/null
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/AbstractMessageType.cs
@@ -0,0 +1,35 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+namespace Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol
+{
+    /// <summary>
+    /// Defines an event type with a particular method name.
+    /// </summary>
+    /// <typeparam name="TParams">The parameter type for this event.</typeparam>
+    public class AbstractMessageType
+    {
+        private string _method;
+        private int _numberOfParams;
+
+        /// <summary>
+        /// Gets the method name for the event type.
+        /// </summary>
+        public string Method { get { return _method; } }
+
+        /// <summary>
+        /// Gets the number of parameters.
+        /// </summary>
+        public int NumberOfParams { get; }
+
+        public AbstractMessageType(string method, int numberOfParams)
+        {
+            _method = method;
+            _numberOfParams = numberOfParams;
+        }
+    }
+}
+
+
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/EventContext.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/EventContext.cs
index e4f4051df..7af362f4e 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/EventContext.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/EventContext.cs
@@ -21,8 +21,8 @@ public EventContext(MessageWriter messageWriter)
             this.messageWriter = messageWriter;
         }
 
-        public async Task SendEvent<TParams>(
-            EventType<TParams> eventType, 
+        public async Task SendEvent<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             TParams eventParams)
         {
             await this.messageWriter.WriteEvent(
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/EventType.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/EventType.cs
index 1b2fe1893..58e2f1f59 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/EventType.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/EventType.cs
@@ -9,24 +9,21 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol
     /// Defines an event type with a particular method name.
     /// </summary>
     /// <typeparam name="TParams">The parameter type for this event.</typeparam>
-    public class EventType<TParams>
+    public class NotificationType<TParams, TRegistrationOptions> : AbstractMessageType
     {
-        /// <summary>
-        /// Gets the method name for the event type.
-        /// </summary>
-        public string MethodName { get; private set; }
+        private NotificationType(string method) : base(method, 1)
+        {
+
+        }
 
         /// <summary>
         /// Creates an EventType instance with the given parameter type and method name.
         /// </summary>
-        /// <param name="methodName">The method name of the event.</param>
+        /// <param name="method">The method name of the event.</param>
         /// <returns>A new EventType instance for the defined type.</returns>
-        public static EventType<TParams> Create(string methodName)
+        public static NotificationType<TParams, TRegistrationOptions> Create(string method)
         {
-            return new EventType<TParams>()
-            {
-                MethodName = methodName
-            };
+            return new NotificationType<TParams, TRegistrationOptions>(method);
         }
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/IMessageSender.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/IMessageSender.cs
index 804743573..5b4da2452 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/IMessageSender.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/IMessageSender.cs
@@ -9,12 +9,12 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol
 {
     internal interface IMessageSender
     {
-        Task SendEvent<TParams>(
-            EventType<TParams> eventType,
+        Task SendEvent<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             TParams eventParams);
 
-        Task<TResult> SendRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        Task<TResult> SendRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams,
             bool waitForResponse);
     }
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageDispatcher.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageDispatcher.cs
index cda98a884..995d124d7 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageDispatcher.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageDispatcher.cs
@@ -92,8 +92,8 @@ public void Stop()
             }
         }
 
-        public void SetRequestHandler<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        public void SetRequestHandler<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             Func<TParams, RequestContext<TResult>, Task> requestHandler)
         {
             this.SetRequestHandler(
@@ -102,19 +102,19 @@ public void SetRequestHandler<TParams, TResult>(
                 false);
         }
 
-        public void SetRequestHandler<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        public void SetRequestHandler<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             Func<TParams, RequestContext<TResult>, Task> requestHandler,
             bool overrideExisting)
         {
             if (overrideExisting)
             {
                 // Remove the existing handler so a new one can be set
-                this.requestHandlers.Remove(requestType.MethodName);
+                this.requestHandlers.Remove(requestType.Method);
             }
 
             this.requestHandlers.Add(
-                requestType.MethodName,
+                requestType.Method,
                 (requestMessage, messageWriter) =>
                 {
                     var requestContext =
@@ -133,8 +133,8 @@ public void SetRequestHandler<TParams, TResult>(
                 });
         }
 
-        public void SetEventHandler<TParams>(
-            EventType<TParams> eventType,
+        public void SetEventHandler<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             Func<TParams, EventContext, Task> eventHandler)
         {
             this.SetEventHandler(
@@ -143,19 +143,19 @@ public void SetEventHandler<TParams>(
                 false);
         }
 
-        public void SetEventHandler<TParams>(
-            EventType<TParams> eventType,
+        public void SetEventHandler<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             Func<TParams, EventContext, Task> eventHandler,
             bool overrideExisting)
         {
             if (overrideExisting)
             {
                 // Remove the existing handler so a new one can be set
-                this.eventHandlers.Remove(eventType.MethodName);
+                this.eventHandlers.Remove(eventType.Method);
             }
 
             this.eventHandlers.Add(
-                eventType.MethodName,
+                eventType.Method,
                 (eventMessage, messageWriter) =>
                 {
                     var eventContext = new EventContext(messageWriter);
@@ -263,7 +263,7 @@ await this.DispatchMessage(
         }
 
         protected async Task DispatchMessage(
-            Message messageToDispatch, 
+            Message messageToDispatch,
             MessageWriter messageWriter)
         {
             Task handlerToAwait = null;
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageWriter.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageWriter.cs
index 28fbe1eb6..b1936d40e 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageWriter.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/MessageWriter.cs
@@ -21,7 +21,7 @@ public class MessageWriter
         private IMessageSerializer messageSerializer;
         private AsyncLock writeLock = new AsyncLock();
 
-        private JsonSerializer contentSerializer = 
+        private JsonSerializer contentSerializer =
             JsonSerializer.Create(
                 Constants.JsonSerializerSettings);
 
@@ -71,7 +71,7 @@ public async Task WriteMessage(Message messageToWrite)
                     Constants.JsonSerializerSettings);
 
             byte[] messageBytes = Encoding.UTF8.GetBytes(serializedMessage);
-            byte[] headerBytes = 
+            byte[] headerBytes =
                 Encoding.ASCII.GetBytes(
                     string.Format(
                         Constants.ContentLengthFormatString,
@@ -89,8 +89,8 @@ public async Task WriteMessage(Message messageToWrite)
             }
         }
 
-        public async Task WriteRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType, 
+        public async Task WriteRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams,
             int requestId)
         {
@@ -102,8 +102,8 @@ public async Task WriteRequest<TParams, TResult>(
 
             await this.WriteMessage(
                 Message.Request(
-                    requestId.ToString(), 
-                    requestType.MethodName,
+                    requestId.ToString(),
+                    requestType.Method,
                     contentObject));
         }
 
@@ -122,7 +122,7 @@ await this.WriteMessage(
                     contentObject));
         }
 
-        public async Task WriteEvent<TParams>(EventType<TParams> eventType, TParams eventParams)
+        public async Task WriteEvent<TParams, TRegistrationOptions>(NotificationType<TParams, TRegistrationOptions> eventType, TParams eventParams)
         {
             // Allow null content
             JToken contentObject =
@@ -132,7 +132,7 @@ public async Task WriteEvent<TParams>(EventType<TParams> eventType, TParams even
 
             await this.WriteMessage(
                 Message.Event(
-                    eventType.MethodName,
+                    eventType.Method,
                     contentObject));
         }
 
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/ProtocolEndpoint.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/ProtocolEndpoint.cs
index 92aed5ecb..9ef13c828 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/ProtocolEndpoint.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/ProtocolEndpoint.cs
@@ -59,7 +59,7 @@ public ProtocolEndpoint(
             this.messageProtocolType = messageProtocolType;
             this.originalSynchronizationContext = SynchronizationContext.Current;
         }
-        
+
         /// <summary>
         /// Starts the language server client and sends the Initialize method.
         /// </summary>
@@ -132,6 +132,15 @@ public async Task Stop()
 
         #region Message Sending
 
+        public Task<TResult> SendRequest<TResult, TError, TRegistrationOptions>(
+            RequestType0<TResult, TError, TRegistrationOptions> requestType0)
+        {
+            return this.SendRequest(
+                RequestType<Object, TResult, TError, TRegistrationOptions>.ConvertToRequestType(requestType0),
+                 null);
+        }
+
+
         /// <summary>
         /// Sends a request to the server
         /// </summary>
@@ -140,15 +149,15 @@ public async Task Stop()
         /// <param name="requestType"></param>
         /// <param name="requestParams"></param>
         /// <returns></returns>
-        public Task<TResult> SendRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType, 
+        public Task<TResult> SendRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams)
         {
             return this.SendRequest(requestType, requestParams, true);
         }
 
-        public async Task<TResult> SendRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType, 
+        public async Task<TResult> SendRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams,
             bool waitForResponse)
         {
@@ -173,13 +182,13 @@ public async Task<TResult> SendRequest<TParams, TResult>(
             {
                 responseTask = new TaskCompletionSource<Message>();
                 this.pendingRequests.Add(
-                    this.currentMessageId.ToString(), 
+                    this.currentMessageId.ToString(),
                     responseTask);
             }
 
-            await this.protocolChannel.MessageWriter.WriteRequest<TParams, TResult>(
-                requestType, 
-                requestParams, 
+            await this.protocolChannel.MessageWriter.WriteRequest<TParams, TResult, TError, TRegistrationOptions>(
+                requestType,
+                requestParams,
                 this.currentMessageId);
 
             if (responseTask != null)
@@ -205,8 +214,8 @@ await this.protocolChannel.MessageWriter.WriteRequest<TParams, TResult>(
         /// <param name="eventType">The type of event being sent.</param>
         /// <param name="eventParams">The event parameters being sent.</param>
         /// <returns>A Task that tracks completion of the send operation.</returns>
-        public Task SendEvent<TParams>(
-            EventType<TParams> eventType,
+        public Task SendEvent<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             TParams eventParams)
         {
             // Some requests may still be in the SynchronizationContext queue
@@ -254,8 +263,20 @@ await this.protocolChannel.MessageWriter.WriteEvent(
 
         #region Message Handling
 
-        public void SetRequestHandler<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        public void SetRequestHandler<TResult, TError, TRegistrationOptions>(
+            RequestType0<TResult, TError, TRegistrationOptions> requestType0,
+            Func<RequestContext<TResult>, Task> requestHandler)
+        {
+            SetRequestHandler(
+                RequestType<Object, TResult, TError, TRegistrationOptions>.ConvertToRequestType(requestType0),
+                (param1, requestContext) =>
+                {
+                    return requestHandler(requestContext);
+                });
+        }
+
+        public void SetRequestHandler<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             Func<TParams, RequestContext<TResult>, Task> requestHandler)
         {
             this.MessageDispatcher.SetRequestHandler(
@@ -263,8 +284,8 @@ public void SetRequestHandler<TParams, TResult>(
                 requestHandler);
         }
 
-        public void SetEventHandler<TParams>(
-            EventType<TParams> eventType,
+        public void SetEventHandler<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             Func<TParams, EventContext, Task> eventHandler)
         {
             this.MessageDispatcher.SetEventHandler(
@@ -273,8 +294,8 @@ public void SetEventHandler<TParams>(
                 false);
         }
 
-        public void SetEventHandler<TParams>(
-            EventType<TParams> eventType,
+        public void SetEventHandler<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             Func<TParams, EventContext, Task> eventHandler,
             bool overrideExisting)
         {
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestContext.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestContext.cs
index a578f4668..55c473f01 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestContext.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestContext.cs
@@ -27,7 +27,7 @@ await this.messageWriter.WriteResponse<TResult>(
                 requestMessage.Id);
         }
 
-        public async Task SendEvent<TParams>(EventType<TParams> eventType, TParams eventParams)
+        public async Task SendEvent<TParams, TRegistrationOptions>(NotificationType<TParams, TRegistrationOptions> eventType, TParams eventParams)
         {
             await this.messageWriter.WriteEvent(
                 eventType,
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType.cs
index e5d0cea08..d7c5a6e8e 100644
--- a/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType.cs
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType.cs
@@ -7,17 +7,28 @@
 
 namespace Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol
 {
-    [DebuggerDisplay("RequestType MethodName = {MethodName}")]
-    public class RequestType<TParams, TResult>
+    [DebuggerDisplay("RequestType Method = {Method}")]
+    public class RequestType<TParams, TResult, TError, TRegistrationOptions> : AbstractMessageType
     {
-        public string MethodName { get; private set; }
+        private RequestType(string method) : base(method, 1)
+        {
+
+        }
 
-        public static RequestType<TParams, TResult> Create(string typeName)
+        public static RequestType<TParams, TResult, TError, TRegistrationOptions> ConvertToRequestType(
+            RequestType0<TResult, TError, TRegistrationOptions> requestType0)
         {
-            return new RequestType<TParams, TResult>()
+            return RequestType<TParams, TResult, TError, TRegistrationOptions>.Create(requestType0.Method);
+        }
+
+        public static RequestType<TParams, TResult, TError, TRegistrationOptions> Create(string method)
+        {
+            if (method == null)
             {
-                MethodName = typeName
-            };
+                throw new System.ArgumentNullException(nameof(method));
+            }
+
+            return new RequestType<TParams, TResult, TError, TRegistrationOptions>(method);
         }
     }
 }
diff --git a/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType0.cs b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType0.cs
new file mode 100644
index 000000000..e8fc8da1c
--- /dev/null
+++ b/src/PowerShellEditorServices.Protocol/MessageProtocol/RequestType0.cs
@@ -0,0 +1,22 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Diagnostics;
+
+namespace Microsoft.PowerShell.EditorServices.Protocol.MessageProtocol
+{
+    [DebuggerDisplay("RequestType0 Method = {Method}")]
+    public class RequestType0<TResult, TError, TRegistrationOptions> : AbstractMessageType
+    {
+        public RequestType0(string method) : base(method, 0)
+        {
+        }
+
+        public static RequestType0<TResult, TError, TRegistrationOptions> Create(string method)
+        {
+            return new RequestType0<TResult, TError, TRegistrationOptions>(method);
+        }
+    }
+}
diff --git a/src/PowerShellEditorServices.Protocol/Messages/PromptEvents.cs b/src/PowerShellEditorServices.Protocol/Messages/PromptEvents.cs
index 031b996af..3a04eaf1e 100644
--- a/src/PowerShellEditorServices.Protocol/Messages/PromptEvents.cs
+++ b/src/PowerShellEditorServices.Protocol/Messages/PromptEvents.cs
@@ -10,8 +10,8 @@ namespace Microsoft.PowerShell.EditorServices.Protocol.Messages
     public class ShowChoicePromptRequest
     {
         public static readonly
-            RequestType<ShowChoicePromptRequest, ShowChoicePromptResponse> Type =
-            RequestType<ShowChoicePromptRequest, ShowChoicePromptResponse>.Create("powerShell/showChoicePrompt");
+            RequestType<ShowChoicePromptRequest, ShowChoicePromptResponse, object, object> Type =
+            RequestType<ShowChoicePromptRequest, ShowChoicePromptResponse, object, object>.Create("powerShell/showChoicePrompt");
 
         public bool IsMultiChoice { get; set; }
 
@@ -34,8 +34,8 @@ public class ShowChoicePromptResponse
     public class ShowInputPromptRequest
     {
         public static readonly
-            RequestType<ShowInputPromptRequest, ShowInputPromptResponse> Type =
-            RequestType<ShowInputPromptRequest, ShowInputPromptResponse>.Create("powerShell/showInputPrompt");
+            RequestType<ShowInputPromptRequest, ShowInputPromptResponse, object, object> Type =
+            RequestType<ShowInputPromptRequest, ShowInputPromptResponse, object, object>.Create("powerShell/showInputPrompt");
 
         /// <summary>
         /// Gets or sets the name of the field.
diff --git a/src/PowerShellEditorServices.Protocol/Server/DebugAdapter.cs b/src/PowerShellEditorServices.Protocol/Server/DebugAdapter.cs
index f82c316f3..cdc059e43 100644
--- a/src/PowerShellEditorServices.Protocol/Server/DebugAdapter.cs
+++ b/src/PowerShellEditorServices.Protocol/Server/DebugAdapter.cs
@@ -926,7 +926,7 @@ async void powerShellContext_RunspaceChanged(object sender, RunspaceChangedEvent
                 // Exited the session while the debugger is stopped,
                 // send a ContinuedEvent so that the client changes the
                 // UI to appear to be running again
-                await this.SendEvent<ContinuedEvent>(
+                await this.SendEvent<ContinuedEvent, Object>(
                     ContinuedEvent.Type,
                     new ContinuedEvent
                     {
diff --git a/src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs b/src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs
index 629d2f0bb..ede85beba 100644
--- a/src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs
+++ b/src/PowerShellEditorServices.Protocol/Server/LanguageServer.cs
@@ -174,7 +174,7 @@ protected override async Task Shutdown()
         #region Built-in Message Handlers
 
         protected async Task HandleInitializeRequest(
-            InitializeRequest initializeParams,
+            InitializeParams initializeParams,
             RequestContext<InitializeResult> requestContext)
         {
             // Grab the workspace path from the parameters
@@ -483,13 +483,13 @@ private async Task HandleFindModuleRequest(
         }
 
         protected Task HandleDidOpenTextDocumentNotification(
-            DidOpenTextDocumentNotification openParams,
+            DidOpenTextDocumentParams openParams,
             EventContext eventContext)
         {
             ScriptFile openedFile =
                 editorSession.Workspace.GetFileBuffer(
-                    openParams.Uri,
-                    openParams.Text);
+                    openParams.TextDocument.Uri,
+                    openParams.TextDocument.Text);
 
             // TODO: Get all recently edited files in the workspace
             this.RunScriptDiagnostics(
@@ -503,11 +503,11 @@ protected Task HandleDidOpenTextDocumentNotification(
         }
 
         protected async Task HandleDidCloseTextDocumentNotification(
-            TextDocumentIdentifier closeParams,
+            DidCloseTextDocumentParams closeParams,
             EventContext eventContext)
         {
             // Find and close the file in the current session
-            var fileToClose = editorSession.Workspace.GetFile(closeParams.Uri);
+            var fileToClose = editorSession.Workspace.GetFile(closeParams.TextDocument.Uri);
 
             if (fileToClose != null)
             {
@@ -544,7 +544,7 @@ protected Task HandleDidChangeTextDocumentNotification(
             // A text change notification can batch multiple change requests
             foreach (var textChange in textChangeParams.ContentChanges)
             {
-                ScriptFile changedFile = editorSession.Workspace.GetFile(textChangeParams.Uri);
+                ScriptFile changedFile = editorSession.Workspace.GetFile(textChangeParams.TextDocument.Uri);
 
                 changedFile.ApplyChange(
                     GetFileChangeDetails(
@@ -708,15 +708,15 @@ await editorSession.LanguageService.FindReferencesOfSymbol(
         }
 
         protected async Task HandleCompletionRequest(
-            TextDocumentPosition textDocumentPosition,
+            TextDocumentPositionParams textDocumentPositionParams,
             RequestContext<CompletionItem[]> requestContext)
         {
-            int cursorLine = textDocumentPosition.Position.Line + 1;
-            int cursorColumn = textDocumentPosition.Position.Character + 1;
+            int cursorLine = textDocumentPositionParams.Position.Line + 1;
+            int cursorColumn = textDocumentPositionParams.Position.Character + 1;
 
             ScriptFile scriptFile =
                 editorSession.Workspace.GetFile(
-                    textDocumentPosition.Uri);
+                    textDocumentPositionParams.TextDocument.Uri);
 
             CompletionResults completionResults =
                 await editorSession.LanguageService.GetCompletionsInFile(
@@ -773,18 +773,18 @@ await CommandHelpers.GetCommandSynopsis(
         }
 
         protected async Task HandleSignatureHelpRequest(
-            TextDocumentPosition textDocumentPosition,
+            TextDocumentPositionParams textDocumentPositionParams,
             RequestContext<SignatureHelp> requestContext)
         {
             ScriptFile scriptFile =
                 editorSession.Workspace.GetFile(
-                    textDocumentPosition.Uri);
+                    textDocumentPositionParams.TextDocument.Uri);
 
             ParameterSetSignatures parameterSets =
                 await editorSession.LanguageService.FindParameterSetsInFile(
                     scriptFile,
-                    textDocumentPosition.Position.Line + 1,
-                    textDocumentPosition.Position.Character + 1);
+                    textDocumentPositionParams.Position.Line + 1,
+                    textDocumentPositionParams.Position.Character + 1);
 
             SignatureInformation[] signatures = null;
             int? activeParameter = null;
@@ -824,18 +824,18 @@ await requestContext.SendResult(
         }
 
         protected async Task HandleDocumentHighlightRequest(
-            TextDocumentPosition textDocumentPosition,
+            TextDocumentPositionParams textDocumentPositionParams,
             RequestContext<DocumentHighlight[]> requestContext)
         {
             ScriptFile scriptFile =
                 editorSession.Workspace.GetFile(
-                    textDocumentPosition.Uri);
+                    textDocumentPositionParams.TextDocument.Uri);
 
             FindOccurrencesResult occurrencesResult =
                 editorSession.LanguageService.FindOccurrencesInFile(
                     scriptFile,
-                    textDocumentPosition.Position.Line + 1,
-                    textDocumentPosition.Position.Character + 1);
+                    textDocumentPositionParams.Position.Line + 1,
+                    textDocumentPositionParams.Position.Character + 1);
 
             DocumentHighlight[] documentHighlights = null;
 
@@ -863,20 +863,20 @@ protected async Task HandleDocumentHighlightRequest(
         }
 
         protected async Task HandleHoverRequest(
-            TextDocumentPosition textDocumentPosition,
+            TextDocumentPositionParams textDocumentPositionParams,
             RequestContext<Hover> requestContext)
         {
             ScriptFile scriptFile =
                 editorSession.Workspace.GetFile(
-                    textDocumentPosition.Uri);
+                    textDocumentPositionParams.TextDocument.Uri);
 
             SymbolDetails symbolDetails =
                 await editorSession
                     .LanguageService
                     .FindSymbolDetailsAtLocation(
                         scriptFile,
-                        textDocumentPosition.Position.Line + 1,
-                        textDocumentPosition.Position.Character + 1);
+                        textDocumentPositionParams.Position.Line + 1,
+                        textDocumentPositionParams.Position.Character + 1);
 
             List<MarkedString> symbolInfo = new List<MarkedString>();
             Range? symbolRange = null;
@@ -912,12 +912,12 @@ await requestContext.SendResult(
         }
 
         protected async Task HandleDocumentSymbolRequest(
-            TextDocumentIdentifier textDocumentIdentifier,
+            DocumentSymbolParams documentSymbolParams,
             RequestContext<SymbolInformation[]> requestContext)
         {
             ScriptFile scriptFile =
                 editorSession.Workspace.GetFile(
-                    textDocumentIdentifier.Uri);
+                    documentSymbolParams.TextDocument.Uri);
 
             FindOccurrencesResult foundSymbols =
                 editorSession.LanguageService.FindSymbolsInFile(
@@ -1078,7 +1078,7 @@ private bool IsQueryMatch(string query, string symbolName)
         }
 
         protected async Task HandleCodeActionRequest(
-            CodeActionRequest codeActionParams,
+            CodeActionParams codeActionParams,
             RequestContext<CodeActionCommand[]> requestContext)
         {
             MarkerCorrection correction = null;
@@ -1249,7 +1249,7 @@ private Task RunScriptDiagnostics(
         private Task RunScriptDiagnostics(
             ScriptFile[] filesToAnalyze,
             EditorSession editorSession,
-            Func<EventType<PublishDiagnosticsNotification>, PublishDiagnosticsNotification, Task> eventSender)
+            Func<NotificationType<PublishDiagnosticsNotification, object>, PublishDiagnosticsNotification, Task> eventSender)
         {
             // If there's an existing task, attempt to cancel it
             try
@@ -1327,7 +1327,7 @@ private static async Task DelayThenInvokeDiagnostics(
             bool isScriptAnalysisEnabled,
             Dictionary<string, Dictionary<string, MarkerCorrection>> correctionIndex,
             EditorSession editorSession,
-            Func<EventType<PublishDiagnosticsNotification>, PublishDiagnosticsNotification, Task> eventSender,
+            Func<NotificationType<PublishDiagnosticsNotification, object>, PublishDiagnosticsNotification, Task> eventSender,
             CancellationToken cancellationToken)
         {
             // First of all, wait for the desired delay period before
@@ -1403,7 +1403,7 @@ private static async Task PublishScriptDiagnostics(
             ScriptFile scriptFile,
             ScriptFileMarker[] markers,
             Dictionary<string, Dictionary<string, MarkerCorrection>> correctionIndex,
-            Func<EventType<PublishDiagnosticsNotification>, PublishDiagnosticsNotification, Task> eventSender)
+            Func<NotificationType<PublishDiagnosticsNotification, object>, PublishDiagnosticsNotification, Task> eventSender)
         {
             List<Diagnostic> diagnostics = new List<Diagnostic>();
 
diff --git a/src/PowerShellEditorServices.Protocol/Server/LanguageServerBase.cs b/src/PowerShellEditorServices.Protocol/Server/LanguageServerBase.cs
index d23391785..7f912cfba 100644
--- a/src/PowerShellEditorServices.Protocol/Server/LanguageServerBase.cs
+++ b/src/PowerShellEditorServices.Protocol/Server/LanguageServerBase.cs
@@ -14,7 +14,7 @@ public abstract class LanguageServerBase : ProtocolEndpoint
     {
         private ChannelBase serverChannel;
 
-        public LanguageServerBase(ChannelBase serverChannel) : 
+        public LanguageServerBase(ChannelBase serverChannel) :
             base(serverChannel, MessageProtocolType.LanguageServer)
         {
             this.serverChannel = serverChannel;
@@ -55,7 +55,6 @@ protected virtual Task Shutdown()
         }
 
         private async Task HandleShutdownRequest(
-            object shutdownParams,
             RequestContext<object> requestContext)
         {
             // Allow the implementor to shut down gracefully
diff --git a/test/PowerShellEditorServices.Test.Channel.WebSocket/WebSocketChannelTest.cs b/test/PowerShellEditorServices.Test.Channel.WebSocket/WebSocketChannelTest.cs
index 71d94c1a8..bfc74168d 100644
--- a/test/PowerShellEditorServices.Test.Channel.WebSocket/WebSocketChannelTest.cs
+++ b/test/PowerShellEditorServices.Test.Channel.WebSocket/WebSocketChannelTest.cs
@@ -50,7 +50,7 @@ await this.SendRequest(
         }
 
         private Task<TResult> SendRequest<TParams, TResult>(
-                RequestType<TParams, TResult> requestType,
+                RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
                 TParams requestParams)
                     {
                         return
diff --git a/test/PowerShellEditorServices.Test.Host/LanguageServerTests.cs b/test/PowerShellEditorServices.Test.Host/LanguageServerTests.cs
index 4b6c0e527..7ca874794 100644
--- a/test/PowerShellEditorServices.Test.Host/LanguageServerTests.cs
+++ b/test/PowerShellEditorServices.Test.Host/LanguageServerTests.cs
@@ -122,9 +122,12 @@ public async Task ServiceCompletesFunctionName()
             CompletionItem[] completions =
                 await this.SendRequest(
                     CompletionRequest.Type,
-                    new TextDocumentPosition
+                    new TextDocumentPositionParams
                     {
-                        Uri = "TestFiles\\CompleteFunctionName.ps1",
+                        TextDocument = new TextDocumentIdentifier
+                        {
+                            Uri = "TestFiles\\CompleteFunctionName.ps1",
+                        },
                         Position = new Position
                         {
                             Line = 4,
@@ -146,9 +149,12 @@ public async Task CompletesDetailOnVariableSuggestion()
             CompletionItem[] completions =
                 await this.SendRequest(
                     CompletionRequest.Type,
-                    new TextDocumentPosition
+                    new TextDocumentPositionParams
                     {
-                        Uri = "TestFiles\\CompleteFunctionName.ps1",
+                        TextDocument = new TextDocumentIdentifier
+                        {
+                            Uri = "TestFiles\\CompleteFunctionName.ps1"
+                        },
                         Position = new Position
                         {
                             Line = 3,
@@ -172,9 +178,12 @@ public async Task CompletesDetailOnVariableDocSuggestion()
 
             await this.SendRequest(
                 CompletionRequest.Type,
-                new TextDocumentPosition
+                new TextDocumentPositionParams
                 {
-                    Uri = "TestFiles\\CompleteFunctionName.ps1",
+                    TextDocument = new TextDocumentIdentifier
+                    {
+                        Uri = "TestFiles\\CompleteFunctionName.ps1"
+                    },
                     Position = new Position
                     {
                         Line = 7,
@@ -212,9 +221,12 @@ public async Task CompletesDetailOnCommandSuggestion()
             CompletionItem[] completions =
                 await this.SendRequest(
                     CompletionRequest.Type,
-                    new TextDocumentPosition
+                    new TextDocumentPositionParams
                     {
-                        Uri = "TestFiles\\CompleteFunctionName.ps1",
+                        TextDocument = new TextDocumentIdentifier
+                        {
+                            Uri = "TestFiles\\CompleteFunctionName.ps1"
+                        },
                         Position = new Position
                         {
                             Line = 5,
@@ -430,9 +442,12 @@ public async Task FindsOccurencesOnFunctionDefinition()
             DocumentHighlight[] highlights =
                 await this.SendRequest(
                     DocumentHighlightRequest.Type,
-                    new TextDocumentPosition
+                    new TextDocumentPositionParams
                     {
-                        Uri = "TestFiles\\FindReferences.ps1",
+                        TextDocument = new TextDocumentIdentifier
+                        {
+                            Uri = "TestFiles\\FindReferences.ps1"
+                        },
                         Position = new Position
                         {
                             Line = 0,
@@ -453,9 +468,12 @@ public async Task GetsParameterHintsOnCommand()
             SignatureHelp signatureHelp =
                 await this.SendRequest(
                     SignatureHelpRequest.Type,
-                    new TextDocumentPosition
+                    new TextDocumentPositionParams
                     {
-                        Uri = "TestFiles\\FindReferences.ps1",
+                        TextDocument = new TextDocumentIdentifier
+                        {
+                            Uri = "TestFiles\\FindReferences.ps1"
+                        },
                         Position = new Position
                         {
                             Line = 12,
@@ -746,10 +764,15 @@ private async Task SendOpenFileEvent(string filePath, bool waitForDiagnostics =
 
             await this.SendEvent(
                 DidOpenTextDocumentNotification.Type,
-                new DidOpenTextDocumentNotification()
+                new DidOpenTextDocumentParams
                 {
-                    Uri = filePath,
-                    Text = fileContents
+                    TextDocument = new TextDocumentItem
+                    {
+                        Uri = filePath,
+                        Text = fileContents,
+                        LanguageId = "PowerShell",
+                        Version = 0
+                    }
                 });
 
             if (diagnosticWaitTask != null)
@@ -758,4 +781,4 @@ await this.SendEvent(
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/test/PowerShellEditorServices.Test.Host/ServerTestsBase.cs b/test/PowerShellEditorServices.Test.Host/ServerTestsBase.cs
index d7e7f3e2a..e65983b1a 100644
--- a/test/PowerShellEditorServices.Test.Host/ServerTestsBase.cs
+++ b/test/PowerShellEditorServices.Test.Host/ServerTestsBase.cs
@@ -102,19 +102,16 @@ protected async Task<Tuple<int, int>> LaunchService(
             {
                 // Must have read an error?  Keep reading from error stream
                 string errorString = completedRead.Result;
+                Task<string> errorRead = this.serviceProcess.StandardError.ReadToEndAsync();
 
-                while (true)
+                // Lets give the read operation 5 seconds to complete. Ideally, it shouldn't
+                // take that long at all, but just in case...
+                if (errorRead.Wait(5000))
                 {
-                    Task<string> errorRead = this.serviceProcess.StandardError.ReadLineAsync();
-
                     if (!string.IsNullOrEmpty(errorRead.Result))
                     {
                         errorString += errorRead.Result + Environment.NewLine;
                     }
-                    else
-                    {
-                        break;
-                    }
                 }
 
                 throw new Exception("Could not launch powershell.exe:\r\n\r\n" + errorString);
@@ -134,8 +131,8 @@ protected void KillService()
             }
         }
 
-        protected Task<TResult> SendRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        protected Task<TResult> SendRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams)
         {
             return
@@ -144,7 +141,7 @@ protected Task<TResult> SendRequest<TParams, TResult>(
                     requestParams);
         }
 
-        protected Task SendEvent<TParams>(EventType<TParams> eventType, TParams eventParams)
+        protected Task SendEvent<TParams, TRegistrationOptions>(NotificationType<TParams, TRegistrationOptions> eventType, TParams eventParams)
         {
             return
                 this.protocolClient.SendEvent(
@@ -152,11 +149,11 @@ protected Task SendEvent<TParams>(EventType<TParams> eventType, TParams eventPar
                     eventParams);
         }
 
-        protected void QueueEventsForType<TParams>(EventType<TParams> eventType)
+        protected void QueueEventsForType<TParams, TRegistrationOptions>(NotificationType<TParams, TRegistrationOptions> eventType)
         {
             var eventQueue =
                 this.eventQueuePerType.AddOrUpdate(
-                    eventType.MethodName,
+                    eventType.Method,
                     new AsyncQueue<object>(),
                     (key, queue) => queue);
 
@@ -168,15 +165,15 @@ protected void QueueEventsForType<TParams>(EventType<TParams> eventType)
                 });
         }
 
-        protected async Task<TParams> WaitForEvent<TParams>(
-            EventType<TParams> eventType,
+        protected async Task<TParams> WaitForEvent<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             int timeoutMilliseconds = 5000)
         {
             Task<TParams> eventTask = null;
 
             // Use the event queue if one has been registered
             AsyncQueue<object> eventQueue = null;
-            if (this.eventQueuePerType.TryGetValue(eventType.MethodName, out eventQueue))
+            if (this.eventQueuePerType.TryGetValue(eventType.Method, out eventQueue))
             {
                 eventTask =
                     eventQueue
@@ -214,21 +211,21 @@ protected async Task<TParams> WaitForEvent<TParams>(
                 throw new TimeoutException(
                     string.Format(
                         "Timed out waiting for '{0}' event!",
-                        eventType.MethodName));
+                        eventType.Method));
             }
 
             return await eventTask;
         }
 
         protected async Task<Tuple<TParams, RequestContext<TResponse>>> WaitForRequest<TParams, TResponse>(
-            RequestType<TParams, TResponse> requestType,
+            RequestType<TParams, TResponse, object, object> requestType,
             int timeoutMilliseconds = 5000)
         {
             Task<Tuple<TParams, RequestContext<TResponse>>> requestTask = null;
 
             // Use the request queue if one has been registered
             AsyncQueue<object> requestQueue = null;
-            if (this.requestQueuePerType.TryGetValue(requestType.MethodName, out requestQueue))
+            if (this.requestQueuePerType.TryGetValue(requestType.Method, out requestQueue))
             {
                 requestTask =
                     requestQueue
@@ -267,7 +264,7 @@ protected async Task<Tuple<TParams, RequestContext<TResponse>>> WaitForRequest<T
                 throw new TimeoutException(
                     string.Format(
                         "Timed out waiting for '{0}' request!",
-                        requestType.MethodName));
+                        requestType.Method));
             }
 
             return await requestTask;
diff --git a/test/PowerShellEditorServices.Test.Protocol/Server/OutputDebouncerTests.cs b/test/PowerShellEditorServices.Test.Protocol/Server/OutputDebouncerTests.cs
index a8b822a3b..bd15d1a75 100644
--- a/test/PowerShellEditorServices.Test.Protocol/Server/OutputDebouncerTests.cs
+++ b/test/PowerShellEditorServices.Test.Protocol/Server/OutputDebouncerTests.cs
@@ -99,8 +99,8 @@ internal class TestMessageSender : IMessageSender
     {
         public List<OutputEventBody> OutputEvents { get; } = new List<OutputEventBody>();
 
-        public Task SendEvent<TParams>(
-            EventType<TParams> eventType,
+        public Task SendEvent<TParams, TRegistrationOptions>(
+            NotificationType<TParams, TRegistrationOptions> eventType,
             TParams eventParams)
         {
             OutputEventBody outputEvent = eventParams as OutputEventBody;
@@ -113,8 +113,8 @@ public Task SendEvent<TParams>(
             return Task.FromResult(true);
         }
 
-        public Task<TResult> SendRequest<TParams, TResult>(
-            RequestType<TParams, TResult> requestType,
+        public Task<TResult> SendRequest<TParams, TResult, TError, TRegistrationOptions>(
+            RequestType<TParams, TResult, TError, TRegistrationOptions> requestType,
             TParams requestParams, bool waitForResponse)
         {
             // Legitimately not implemented for these tests.