feat(@angular/cli): add --experimental-tool option to mcp command

This change introduces an `--experimental-tool` flag (with a `-E` alias) to the `ng mcp` command. This flag allows users to enable specific experimental tools by providing their names.

Experimental tools are kept separate from the main toolset and are only registered if explicitly enabled via this option. This provides a mechanism for safely developing and testing new tools without exposing them to all users by default.

Author: clydin

packages/angular/cli/src/commands/mcp/cli.ts

@@ -43,10 +43,20 @@ export default class McpCommandModule extends CommandModule implements CommandMo
         type: 'boolean',
         default: false,
         describe: 'Only register tools that do not require internet access.',
+      })
+      .option('experimental-tool', {
+        type: 'string',
+        alias: 'E',
+        array: true,
+        describe: 'Enable an experimental tool.',
       });
   }
 
-  async run(options: { readOnly: boolean; localOnly: boolean }): Promise<void> {
+  async run(options: {
+    readOnly: boolean;
+    localOnly: boolean;
+    experimentalTool: string[] | undefined;
+  }): Promise<void> {
     if (isTTY()) {
       this.context.logger.info(INTERACTIVE_MESSAGE);
 
@@ -58,6 +68,7 @@ export default class McpCommandModule extends CommandModule implements CommandMo
         workspace: this.context.workspace,
         readOnly: options.readOnly,
         localOnly: options.localOnly,
+        experimentalTools: options.experimentalTool,
       },
       this.context.logger,
     );

packages/angular/cli/src/commands/mcp/mcp-server.ts

@@ -15,13 +15,14 @@ import { BEST_PRACTICES_TOOL } from './tools/best-practices';
 import { DOC_SEARCH_TOOL } from './tools/doc-search';
 import { FIND_EXAMPLE_TOOL } from './tools/examples';
 import { LIST_PROJECTS_TOOL } from './tools/projects';
-import { registerTools } from './tools/tool-registry';
+import { McpToolDeclaration, registerTools } from './tools/tool-registry';
 
 export async function createMcpServer(
   context: {
     workspace?: AngularWorkspace;
     readOnly?: boolean;
     localOnly?: boolean;
+    experimentalTools?: string[];
   },
   logger: { warn(text: string): void },
 ): Promise<McpServer> {
@@ -71,6 +72,9 @@ export async function createMcpServer(
     FIND_EXAMPLE_TOOL,
   ];
 
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const experimentalToolDeclarations: McpToolDeclaration<any, any>[] = [];
+
   if (context.readOnly) {
     toolDeclarations = toolDeclarations.filter((tool) => tool.isReadOnly);
   }
@@ -79,6 +83,21 @@ export async function createMcpServer(
     toolDeclarations = toolDeclarations.filter((tool) => tool.isLocalOnly);
   }
 
+  if (context.experimentalTools?.length) {
+    const experimentalToolsMap = new Map(
+      experimentalToolDeclarations.map((tool) => [tool.name, tool]),
+    );
+
+    for (const toolName of context.experimentalTools) {
+      const tool = experimentalToolsMap.get(toolName);
+      if (tool) {
+        toolDeclarations.push(tool);
+      } else {
+        logger.warn(`Unknown experimental tool: ${toolName}`);
+      }
+    }
+  }
+
   await registerTools(
     server,
     {