Add Google credentials provider for authenticating with MCP servers (#4748)

packages/core/src/tools/mcp-client.ts

@@ -16,7 +16,8 @@ import {
   StreamableHTTPClientTransportOptions,
 } from '@modelcontextprotocol/sdk/client/streamableHttp.js';
 import { parse } from 'shell-quote';
-import { MCPServerConfig } from '../config/config.js';
+import { AuthProviderType, MCPServerConfig } from '../config/config.js';
+import { GoogleCredentialProvider } from '../mcp/google-auth-provider.js';
 import { DiscoveredMCPTool } from './mcp-tool.js';
 import { FunctionDeclaration, mcpToTool } from '@google/genai';
 import { ToolRegistry } from './tool-registry.js';
@@ -852,6 +853,29 @@ export async function createTransport(
   mcpServerConfig: MCPServerConfig,
   debugMode: boolean,
 ): Promise<Transport> {
+  if (
+    mcpServerConfig.authProviderType === AuthProviderType.GOOGLE_CREDENTIALS
+  ) {
+    const provider = new GoogleCredentialProvider(mcpServerConfig);
+    const transportOptions:
+      | StreamableHTTPClientTransportOptions
+      | SSEClientTransportOptions = {
+      authProvider: provider,
+    };
+    if (mcpServerConfig.httpUrl) {
+      return new StreamableHTTPClientTransport(
+        new URL(mcpServerConfig.httpUrl),
+        transportOptions,
+      );
+    } else if (mcpServerConfig.url) {
+      return new SSEClientTransport(
+        new URL(mcpServerConfig.url),
+        transportOptions,
+      );
+    }
+    throw new Error('No URL configured for Google Credentials MCP server');
+  }
+
   // Check if we have OAuth configuration or stored tokens
   let accessToken: string | null = null;
   let hasOAuthConfig = mcpServerConfig.oauth?.enabled;