refactor(@angular/cli): expand MCP tool/resource descriptions

packages/angular/cli/BUILD.bazel

@@ -58,6 +58,7 @@ ts_project(
         ":node_modules/pacote",
         ":node_modules/resolve",
         ":node_modules/yargs",
+        ":node_modules/zod",
         "//:node_modules/@angular/core",
         "//:node_modules/@types/ini",
         "//:node_modules/@types/node",

packages/angular/cli/package.json

@@ -38,7 +38,8 @@
     "pacote": "21.0.0",
     "resolve": "1.22.10",
     "semver": "7.7.2",
-    "yargs": "18.0.0"
+    "yargs": "18.0.0",
+    "zod": "3.25.75"
   },
   "ng-update": {
     "migrations": "@schematics/angular/migrations/migration-collection.json",

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

@@ -9,6 +9,7 @@
 import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 import { readFile } from 'node:fs/promises';
 import path from 'node:path';
+import { z } from 'zod';
 import type { AngularWorkspace } from '../../utilities/config';
 import { VERSION } from '../../utilities/version';
 
@@ -28,9 +29,12 @@ export async function createMcpServer(context: {
     'instructions',
     'instructions://best-practices',
     {
-      title: 'Angular System Instructions',
+      title: 'Angular Best Practices and Code Generation Guide',
       description:
-        'A set of instructions to help LLMs generate correct code that follows Angular best practices.',
+        "A comprehensive guide detailing Angular's best practices for code generation and development." +
+        ' This guide should be used as a reference by an LLM to ensure any generated code' +
+        ' adheres to modern Angular standards, including the use of standalone components,' +
+        ' typed forms, modern control flow syntax, and other current conventions.',
       mimeType: 'text/markdown',
     },
     async () => {
@@ -46,32 +50,81 @@ export async function createMcpServer(context: {
   server.registerTool(
     'list_projects',
     {
-      title: 'List projects',
+      title: 'List Angular Projects',
       description:
-        'List projects within an Angular workspace.' +
-        ' This information is read from the `angular.json` file at the root path of the Angular workspace',
+        'Lists the names of all applications and libraries defined within an Angular workspace. ' +
+        'It reads the `angular.json` configuration file to identify the projects. ',
+      annotations: {
+        readOnlyHint: true,
+      },
+      outputSchema: {
+        projects: z.array(
+          z.object({
+            name: z
+              .string()
+              .describe('The name of the project, as defined in the `angular.json` file.'),
+            type: z
+              .enum(['application', 'library'])
+              .optional()
+              .describe(`The type of the project, either 'application' or 'library'.`),
+            root: z
+              .string()
+              .describe('The root directory of the project, relative to the workspace root.'),
+            sourceRoot: z
+              .string()
+              .describe(
+                `The root directory of the project's source files, relative to the workspace root.`,
+              ),
+            selectorPrefix: z
+              .string()
+              .optional()
+              .describe(
+                'The prefix to use for component selectors.' +
+                  ` For example, a prefix of 'app' would result in selectors like '<app-my-component>'.`,
+              ),
+          }),
+        ),
+      },
     },
-    () => {
-      if (!context.workspace) {
+    async () => {
+      const { workspace } = context;
+
+      if (!workspace) {
         return {
           content: [
             {
-              type: 'text',
-              text: 'Not within an Angular project.',
+              type: 'text' as const,
+              text:
+                'No Angular workspace found.' +
+                ' An `angular.json` file, which marks the root of a workspace,' +
+                ' could not be located in the current directory or any of its parent directories.',
             },
           ],
         };
       }
 
+      const projects = [];
+      // Convert to output format
+      for (const [name, project] of workspace.projects.entries()) {
+        projects.push({
+          name,
+          type: project.extensions['projectType'] as 'application' | 'library' | undefined,
+          root: project.root,
+          sourceRoot: project.sourceRoot ?? path.posix.join(project.root, 'src'),
+          selectorPrefix: project.extensions['prefix'] as string,
+        });
+      }
+
+      // The structuredContent field is newer and may not be supported by all hosts.
+      // A text representation of the content is also provided for compatibility.
       return {
         content: [
           {
-            type: 'text',
-            text:
-              'Projects in the Angular workspace: ' +
-              [...context.workspace.projects.keys()].join(','),
+            type: 'text' as const,
+            text: `Projects in the Angular workspace:\n${JSON.stringify(projects)}`,
           },
         ],
+        structuredContent: { projects },
       };
     },
   );