RushDB

Instructions

Implementation Reference

• tools/OpenBrowser.ts:5-54 (handler)

  The core handler function for the OpenBrowser tool. Validates the input URL (only http/https allowed), determines platform-specific browser opener command, and executes it securely using child_process.execFile to open the URL in the default browser.

  export async function OpenBrowser(params: { url: string }) {
    const { url } = params;
    
    // Validate URL to prevent command injection
    let validatedUrl: string;
    try {
      // Validate URL format
      const parsedUrl = new URL(url);
      // Only allow http and https protocols
      if (!['http:', 'https:'].includes(parsedUrl.protocol)) {
        return {
          success: false,
          message: "Invalid URL protocol. Only http and https are supported.",
        };
      }
      validatedUrl = parsedUrl.toString();
    } catch (e) {
      return {
        success: false,
        message: `Invalid URL format: ${e instanceof Error ? e.message : String(e)}`,
      };
    }
    
    // Determine the command based on platform
    const command =
      platform() === "darwin"
        ? "open"
        : platform() === "win32"
        ? "start"
        : "xdg-open";
  
    return new Promise<{ success: boolean; message: string }>(
      (resolve) => {
        // Use execFile instead of exec to prevent command injection
        execFile(command, [validatedUrl], (error) => {
          if (error) {
            resolve({
              success: false,
              message: `Failed to open browser: ${error.message}`,
            });
          } else {
            resolve({
              success: true,
              message: `Successfully opened ${validatedUrl} in default browser`,
            });
          }
        });
      }
    );
  }

• tools.ts:301-309 (schema)

  The input schema and metadata definition for the OpenBrowser tool, used for MCP tool listing and validation.

  {
    name: 'OpenBrowser',
    description: 'Open a web browser to a specific URL',
    inputSchema: {
      type: 'object',
      properties: { url: { type: 'string', description: 'The URL to open' } },
      required: ['url']
    }
  },

• index.ts:318-329 (registration)

  Tool dispatch registration in the MCP CallToolRequestSchema handler's switch statement, which calls the OpenBrowser function with validated arguments and formats the response.

  case 'OpenBrowser':
    const openBrowserResult = await OpenBrowser({
      url: args.url as string
    })
    return {
      content: [
        {
          type: 'text',
          text: openBrowserResult.message
        }
      ]
    }

• index.ts:72-75 (registration)

  Registers the tools list (including OpenBrowser schema) for MCP ListTools requests.

  server.setRequestHandler(ListToolsRequestSchema, async () => {
    return {
      tools
    }

• index.ts:38-38 (registration)

  Imports the OpenBrowser handler function for use in the MCP server.

  import { OpenBrowser } from './tools/OpenBrowser.js'