diff --git a/src/lsptoolshost/openProjectParams.ts b/src/lsptoolshost/openProjectParams.ts
deleted file mode 100644
index bacafcda96..0000000000
--- a/src/lsptoolshost/openProjectParams.ts
+++ /dev/null
@@ -1,10 +0,0 @@
-/*---------------------------------------------------------------------------------------------
- *  Copyright (c) Microsoft Corporation. All rights reserved.
- *  Licensed under the MIT License. See License.txt in the project root for license information.
- *--------------------------------------------------------------------------------------------*/
-
-import { DocumentUri } from 'vscode-languageclient/node';
-
-export class OpenProjectParams {
-    constructor(public readonly projects: DocumentUri[]) {}
-}
diff --git a/src/lsptoolshost/openSolutionParams.ts b/src/lsptoolshost/openSolutionParams.ts
deleted file mode 100644
index 8ca1d34cb7..0000000000
--- a/src/lsptoolshost/openSolutionParams.ts
+++ /dev/null
@@ -1,10 +0,0 @@
-/*---------------------------------------------------------------------------------------------
- *  Copyright (c) Microsoft Corporation. All rights reserved.
- *  Licensed under the MIT License. See License.txt in the project root for license information.
- *--------------------------------------------------------------------------------------------*/
-
-import { DocumentUri } from 'vscode-languageclient/node';
-
-export class OpenSolutionParams {
-    constructor(public readonly solution: DocumentUri) {}
-}
diff --git a/src/lsptoolshost/roslynLanguageServer.ts b/src/lsptoolshost/roslynLanguageServer.ts
index a5a6477782..eb4e8e07ea 100644
--- a/src/lsptoolshost/roslynLanguageServer.ts
+++ b/src/lsptoolshost/roslynLanguageServer.ts
@@ -48,8 +48,6 @@ import ShowInformationMessage from '../shared/observers/utils/showInformationMes
 import EventEmitter = require('events');
 import Disposable from '../disposable';
 import * as RoslynProtocol from './roslynProtocol';
-import { OpenSolutionParams } from './openSolutionParams';
-import { OpenProjectParams } from './openProjectParams';
 import { CSharpDevKitExports } from '../csharpDevKitExports';
 import { ISolutionSnapshotProvider, SolutionSnapshotId } from './services/ISolutionSnapshotProvider';
 import { Options } from '../shared/options';
@@ -338,14 +336,18 @@ export class RoslynLanguageServer {
         if (this._languageClient !== undefined && this._languageClient.isRunning()) {
             if (this._solutionFile !== undefined) {
                 const protocolUri = this._languageClient.clientOptions.uriConverters!.code2Protocol(this._solutionFile);
-                await this._languageClient.sendNotification('solution/open', new OpenSolutionParams(protocolUri));
+                await this._languageClient.sendNotification(RoslynProtocol.OpenSolutionNotification.type, {
+                    solution: protocolUri,
+                });
             }
 
             if (this._projectFiles.length > 0) {
                 const projectProtocolUris = this._projectFiles.map((uri) =>
                     this._languageClient!.clientOptions.uriConverters!.code2Protocol(uri)
                 );
-                await this._languageClient.sendNotification('project/open', new OpenProjectParams(projectProtocolUris));
+                await this._languageClient.sendNotification(RoslynProtocol.OpenProjectNotification.type, {
+                    projects: projectProtocolUris,
+                });
             }
         }
     }
diff --git a/src/lsptoolshost/roslynProtocol.ts b/src/lsptoolshost/roslynProtocol.ts
index e01b5d732b..074a05eeb7 100644
--- a/src/lsptoolshost/roslynProtocol.ts
+++ b/src/lsptoolshost/roslynProtocol.ts
@@ -116,6 +116,14 @@ export interface DebugAttachResult {
     didAttach: boolean;
 }
 
+export interface OpenSolutionParams {
+    solution: lsp.DocumentUri;
+}
+
+export interface OpenProjectParams {
+    projects: lsp.DocumentUri[];
+}
+
 export namespace WorkspaceDebugConfigurationRequest {
     export const method = 'workspace/debugConfiguration';
     export const messageDirection: lsp.MessageDirection = lsp.MessageDirection.clientToServer;
@@ -159,3 +167,15 @@ export namespace DebugAttachRequest {
     export const messageDirection: lsp.MessageDirection = lsp.MessageDirection.serverToClient;
     export const type = new lsp.RequestType<DebugAttachParams, DebugAttachResult, void>(method);
 }
+
+export namespace OpenSolutionNotification {
+    export const method = 'solution/open';
+    export const messageDirection: lsp.MessageDirection = lsp.MessageDirection.clientToServer;
+    export const type = new lsp.NotificationType<OpenSolutionParams>(method);
+}
+
+export namespace OpenProjectNotification {
+    export const method = 'project/open';
+    export const messageDirection: lsp.MessageDirection = lsp.MessageDirection.clientToServer;
+    export const type = new lsp.NotificationType<OpenProjectParams>(method);
+}