[api-extractor] Upgrade bundled TypeScript to 6.0.3

apps/api-extractor/package.json

@@ -78,7 +78,7 @@
     "resolve": "~1.22.1",
     "semver": "~7.7.4",
     "source-map": "~0.6.1",
-    "typescript": "5.9.3"
+    "typescript": "6.0.3"
   },
   "devDependencies": {
     "@rushstack/heft": "1.3.3",

apps/api-extractor/src/analyzer/TypeScriptInternals.ts

@@ -17,7 +17,7 @@ export interface IGlobalVariableAnalyzer {
 export class TypeScriptInternals {
   public static getImmediateAliasedSymbol(symbol: ts.Symbol, typeChecker: ts.TypeChecker): ts.Symbol {
     // Compiler internal:
-    // https://github.com/microsoft/TypeScript/blob/v5.9.3/src/compiler/checker.ts
+    // https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/checker.ts
     return (typeChecker as any).getImmediateAliasedSymbol(symbol);
   }
 
@@ -61,7 +61,7 @@ export class TypeScriptInternals {
    */
   public static getJSDocCommentRanges(node: ts.Node, text: string): ts.CommentRange[] | undefined {
     // Compiler internal:
-    // https://github.com/microsoft/TypeScript/blob/v5.9.3/src/compiler/utilities.ts#L2710
+    // https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/utilities.ts#L2763
 
     return (ts as any).getJSDocCommentRanges.apply(this, arguments);
   }
@@ -73,7 +73,7 @@ export class TypeScriptInternals {
     node: ts.Identifier | ts.StringLiteralLike | ts.NumericLiteral
   ): string {
     // Compiler internal:
-    // https://github.com/microsoft/TypeScript/blob/v5.9.3/src/compiler/utilities.ts#L5368
+    // https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/utilities.ts#L5439
 
     return (ts as any).getTextOfIdentifierOrLiteral(node);
   }
@@ -89,7 +89,7 @@ export class TypeScriptInternals {
     mode: ts.ModuleKind.CommonJS | ts.ModuleKind.ESNext | undefined
   ): ts.ResolvedModuleFull | undefined {
     // Compiler internal:
-    // https://github.com/microsoft/TypeScript/blob/v5.9.3/src/compiler/types.ts#L5064
+    // https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/types.ts#L5056
     const result: ts.ResolvedModuleWithFailedLookupLocations | undefined = (program as any).getResolvedModule(
       sourceFile,
       moduleNameText,
@@ -107,7 +107,7 @@ export class TypeScriptInternals {
     compilerOptions: ts.CompilerOptions
   ): ts.ModuleKind.CommonJS | ts.ModuleKind.ESNext | undefined {
     // Compiler internal:
-    // https://github.com/microsoft/TypeScript/blob/v5.9.3/src/compiler/program.ts#L932
+    // https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/program.ts#L932
 
     return ts.getModeForUsageLocation?.(file, usage, compilerOptions);
   }
@@ -150,7 +150,7 @@ export class TypeScriptInternals {
    * Returns whether a variable is declared with the const keyword
    */
   public static isVarConst(node: ts.VariableDeclaration | ts.VariableDeclarationList): boolean {
-    // Compiler internal: https://github.com/microsoft/TypeScript/blob/71286e3d49c10e0e99faac360a6bbd40f12db7b6/src/compiler/utilities.ts#L925
+    // Compiler internal: https://github.com/microsoft/TypeScript/blob/v6.0.3/src/compiler/utilities.ts#L2677
     return (ts as any).isVarConst(node);
   }
 }

apps/rush-mcp-server/src/pluginFramework/RushMcpPluginLoader.ts

@@ -3,7 +3,7 @@
 
 import * as path from 'node:path';
 
-import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp';
+import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 
 import { FileSystem, Import, JsonFile, type JsonObject, JsonSchema } from '@rushstack/node-core-library';
 import { Autoinstaller } from '@rushstack/rush-sdk/lib/logic/Autoinstaller';

apps/rush-mcp-server/src/pluginFramework/RushMcpPluginSession.ts

@@ -2,7 +2,7 @@
 // See LICENSE in the project root for license information.
 
 import * as zod from 'zod';
-import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp';
+import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 
 import type { IRushMcpTool } from './IRushMcpTool';
 import type { zodModule } from './zodTypes';

apps/rush-mcp-server/src/pluginFramework/zodTypes.ts

@@ -2,7 +2,7 @@
 // See LICENSE in the project root for license information.
 
 import type * as zod from 'zod';
-import { CallToolResultSchema } from '@modelcontextprotocol/sdk/types';
+import { CallToolResultSchema } from '@modelcontextprotocol/sdk/types.js';
 
 export type { zod as zodModule };
 export { CallToolResultSchema };

apps/rush-mcp-server/src/tools/base.tool.ts

@@ -1,13 +1,13 @@
 // Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
 // See LICENSE in the project root for license information.
 
-import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp';
-import type { RequestHandlerExtra } from '@modelcontextprotocol/sdk/shared/protocol';
+import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
+import type { RequestHandlerExtra } from '@modelcontextprotocol/sdk/shared/protocol.js';
 import type {
   CallToolResultSchema,
   ServerNotification,
   ServerRequest
-} from '@modelcontextprotocol/sdk/types';
+} from '@modelcontextprotocol/sdk/types.js';
 import type { z, ZodRawShape, ZodTypeAny } from 'zod';
 
 export type CallToolResult = z.infer<typeof CallToolResultSchema>;

common/changes/@microsoft/api-extractor/ts-6_2026-10-21-12-14-47.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@microsoft/api-extractor",
+      "comment": "Upgrade the bundled compiler engine to TypeScript 6.0.3",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@microsoft/api-extractor"
+}

common/changes/@rushstack/mcp-server/ts-6_2026-10-21-15-08-56.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/mcp-server",
+      "comment": "",
+      "type": "none"
+    }
+  ],
+  "packageName": "@rushstack/mcp-server"
+}

common/config/subspaces/build-tests-subspace/repo-state.json

@@ -1,6 +1,6 @@
 // DO NOT MODIFY THIS FILE MANUALLY BUT DO COMMIT IT. It is generated and used by Rush.
 {
-  "pnpmShrinkwrapHash": "77334f3044ae8f350cc38031dc8902c5fef466df",
+  "pnpmShrinkwrapHash": "517586379117f21706ed44488ff0813f77a1cde4",
   "preferredVersionsHash": "550b4cee0bef4e97db6c6aad726df5149d20e7d9",
-  "packageJsonInjectedDependenciesHash": "dcb9a4c88f5e9d450f7afb9a4b686850ce152453"
+  "packageJsonInjectedDependenciesHash": "f91103d8175484315a07766c30c725d132567cb7"
 }

common/config/subspaces/default/common-versions.json

@@ -108,7 +108,7 @@
 
       "5.8.2",
       // API Extractor bundles a specific TypeScript version because it calls internal APIs
-      "5.9.3"
+      "6.0.3"
     ],
     "source-map": [
       "~0.6.1" // API Extractor is using an older version of source-map because newer versions are async

common/config/subspaces/default/repo-state.json

@@ -1,5 +1,5 @@
 // DO NOT MODIFY THIS FILE MANUALLY BUT DO COMMIT IT. It is generated and used by Rush.
 {
-  "pnpmShrinkwrapHash": "5ed0eabdfff6ff042769698020ac33348d56a95b",
+  "pnpmShrinkwrapHash": "b07ed464dc8949da7ba2c10d1ac2a97f291c842f",
   "preferredVersionsHash": "029c99bd6e65c5e1f25e2848340509811ff9753c"
 }

common/reviews/api/mcp-server.api.md

@@ -4,7 +4,7 @@
 
 ```ts
 
-import { CallToolResultSchema } from '@modelcontextprotocol/sdk/types';
+import { CallToolResultSchema } from '@modelcontextprotocol/sdk/types.js';
 import type * as zodModule from 'zod';
 
 // @public (undocumented)