Address comments

Author: Natallia Harshunova

src/McpResponse.ts

@@ -25,6 +25,7 @@ import type {
 } from './tools/ToolDefinition.js';
 import type {InsightName, TraceResult} from './trace-processing/parse.js';
 import {getInsightOutput, getTraceSummary} from './trace-processing/parse.js';
+import type {InstalledExtension} from './utils/ExtensionRegistry.js';
 import {paginate} from './utils/pagination.js';
 import type {PaginationOptions} from './utils/types.js';
 
@@ -60,6 +61,7 @@ export class McpResponse implements Response {
     types?: string[];
     includePreservedMessages?: boolean;
   };
+  #listExtensions?: boolean;
   #devToolsData?: DevToolsData;
   #tabId?: string;
 
@@ -81,6 +83,10 @@ export class McpResponse implements Response {
     };
   }
 
+  setListExtensions(): void {
+    this.#listExtensions = true;
+  }
+
   setIncludeNetworkRequests(
     value: boolean,
     options?: PaginationOptions & {
@@ -99,9 +105,9 @@ export class McpResponse implements Response {
       pagination:
         options?.pageSize || options?.pageIdx
           ? {
-              pageSize: options.pageSize,
-              pageIdx: options.pageIdx,
-            }
+            pageSize: options.pageSize,
+            pageIdx: options.pageIdx,
+          }
           : undefined,
       resourceTypes: options?.resourceTypes,
       includePreservedRequests: options?.includePreservedRequests,
@@ -126,9 +132,9 @@ export class McpResponse implements Response {
       pagination:
         options?.pageSize || options?.pageIdx
           ? {
-              pageSize: options.pageSize,
-              pageIdx: options.pageIdx,
-            }
+            pageSize: options.pageSize,
+            pageIdx: options.pageIdx,
+          }
           : undefined,
       types: options?.types,
       includePreservedMessages: options?.includePreservedMessages,
@@ -297,6 +303,11 @@ export class McpResponse implements Response {
       }
     }
 
+    let extensions: InstalledExtension[] | undefined;
+    if (this.#listExtensions) {
+      extensions = context.listExtensions();
+    }
+
     let consoleMessages: Array<ConsoleFormatter | IssueFormatter> | undefined;
     if (this.#consoleDataOptions?.include) {
       let messages = context.getConsoleData(
@@ -395,6 +406,7 @@ export class McpResponse implements Response {
       networkRequests,
       traceInsight: this.#attachedTraceInsight,
       traceSummary: this.#attachedTraceSummary,
+      extensions,
     });
   }
 
@@ -409,6 +421,7 @@ export class McpResponse implements Response {
       networkRequests?: NetworkFormatter[];
       traceSummary?: TraceResult;
       traceInsight?: TraceInsightData;
+      extensions?: InstalledExtension[];
     },
   ): {content: Array<TextContent | ImageContent>; structuredContent: object} {
     const response = [`# ${toolName} response`];
@@ -474,6 +487,7 @@ Call ${handleDialog.name} to handle it before continuing.`);
       consoleMessages?: object[];
       traceSummary?: string;
       traceInsights?: Array<{insightName: string; insightKey: string}>;
+      extensions?: object[];
     } = {};
 
     if (this.#tabId) {
@@ -531,6 +545,25 @@ Call ${handleDialog.name} to handle it before continuing.`);
         data.detailedConsoleMessage.toJSONDetailed();
     }
 
+    if (data.extensions) {
+      structuredContent.extensions = data.extensions;
+      response.push('## Extensions');
+      if (data.extensions.length === 0) {
+        response.push('No extensions installed.');
+      } else {
+        const parts = [];
+        for (const extension of data.extensions) {
+          parts.push([
+            `Name: ${extension.name}`,
+            `ID: ${extension.id}`,
+            `Version: ${extension.version}`,
+            `Status: ${extension.isEnabled ? 'Enabled' : 'Disabled'}`,
+          ].join('\n'));
+        }
+        response.push(parts.join('\n\n'));
+      }
+    }
+
     if (this.#networkRequestsOptions?.include) {
       let requests = context.getNetworkRequests(
         this.#networkRequestsOptions?.includePreservedRequests,

src/tools/ToolDefinition.ts

@@ -93,6 +93,7 @@ export interface Response {
     insightSetId: string,
     insightName: InsightName,
   ): void;
+  setListExtensions(): void;
 }
 
 /**

src/tools/extensions.ts

@@ -60,18 +60,7 @@ export const listExtensions = defineTool({
     conditions: [EXTENSIONS_CONDITION],
   },
   schema: {},
-  handler: async (request, response, context) => {
-    const extensions = context.listExtensions();
-    if (extensions.length === 0) {
-      response.appendResponseLine('No extensions installed.');
-      return;
-    }
-    const table = extensions.map(ext => ({
-      Name: ext.name,
-      ID: ext.id,
-      Version: ext.version,
-      Enabled: ext.isEnabled ? 'Yes' : 'No',
-    }));
-    response.appendResponseLine(JSON.stringify(table, null, 2));
+  handler: async (_request, response, _context) => {
+    response.setListExtensions();
   },
 });

src/utils/ExtensionRegistry.ts

@@ -25,19 +25,15 @@ export class ExtensionRegistry {
     const name = manifest.name ?? 'Unknown';
     const version = manifest.version ?? 'Unknown';
 
-    const extension: InstalledExtension = {
+    const extension = {
       id,
       name,
       version,
       isEnabled: true,
       path: extensionPath,
     };
-    this.add(extension);
-    return extension;
-  }
-
-  add(extension: InstalledExtension): void {
     this.#extensions.set(extension.id, extension);
+    return extension;
   }
 
   remove(id: string): void {

tests/McpResponse.test.js.snapshot

@@ -480,3 +480,38 @@ exports[`McpResponse network request filtering > shows no requests when filter m
 ## Network requests
 No requests found.
 `;
+
+exports[`extensions > lists extensions 1`] = `
+# test response
+## Extensions
+Name: Extension 1
+ID: id1
+Version: 1.0
+Status: Enabled
+
+Name: Extension 2
+ID: id2
+Version: 2.0
+Status: Disabled
+`;
+
+exports[`extensions > lists extensions 2`] = `
+{
+  "extensions": [
+    {
+      "id": "id1",
+      "name": "Extension 1",
+      "version": "1.0",
+      "isEnabled": true,
+      "path": "/path/to/ext1"
+    },
+    {
+      "id": "id2",
+      "name": "Extension 2",
+      "version": "2.0",
+      "isEnabled": false,
+      "path": "/path/to/ext2"
+    }
+  ]
+}
+`;

tests/McpResponse.test.ts

@@ -713,3 +713,35 @@ describe('McpResponse network pagination', () => {
     });
   });
 });
+
+describe('extensions', () => {
+  it('lists extensions', async t => {
+    await withMcpContext(async (response, context) => {
+      context.listExtensions = () => [
+        {
+          id: 'id1',
+          name: 'Extension 1',
+          version: '1.0',
+          isEnabled: true,
+          path: '/path/to/ext1',
+        },
+        {
+          id: 'id2',
+          name: 'Extension 2',
+          version: '2.0',
+          isEnabled: false,
+          path: '/path/to/ext2',
+        },
+      ];
+      response.setListExtensions();
+      const { content, structuredContent } = await response.handle(
+        'test',
+        context,
+      );
+
+      t.assert.snapshot?.(getTextContent(content[0]));
+      t.assert.snapshot?.(JSON.stringify(structuredContent, null, 2));
+    });
+  });
+});
+

tests/tools/extensions.test.ts

@@ -8,6 +8,8 @@ import assert from 'node:assert';
 import path from 'node:path';
 import {describe, it} from 'node:test';
 
+import sinon from 'sinon';
+
 import {
   installExtension,
   uninstallExtension,
@@ -74,34 +76,9 @@ describe('extension', () => {
   });
   it('lists installed extensions', async () => {
     await withMcpContext(async (response, context) => {
-      await installExtension.handler(
-        { params: { path: EXTENSION_PATH } },
-        response,
-        context,
-      );
-
+      const setListExtensionsSpy = sinon.spy(response, 'setListExtensions');
       await listExtensions.handler({ params: {} }, response, context);
-
-      const listResponseLine = response.responseLines[1];
-      assert.ok(listResponseLine, 'Response should not be empty');
-      const extensions = JSON.parse(listResponseLine);
-      assert.strictEqual(extensions.length, 1);
-      assert.strictEqual(extensions[0].Name, 'Test Extension');
-      assert.strictEqual(extensions[0].Version, '1.0');
-      assert.strictEqual(extensions[0].Enabled, 'Yes');
-
-      const extensionId = extensions[0].ID;
-      await uninstallExtension.handler(
-        { params: { id: extensionId } },
-        response,
-        context,
-      );
-
-      response.resetResponseLineForTesting();
-      await listExtensions.handler({ params: {} }, response, context);
-
-      const emptyListResponse = response.responseLines[0];
-      assert.strictEqual(emptyListResponse, 'No extensions installed.');
+      assert.ok(setListExtensionsSpy.calledOnce, 'setListExtensions should be called');
     });
   });
 });