fetch_urls

Instructions

Implementation Reference

• src/tools/fetchUrls.ts:77-153 (handler)

  Main implementation of the fetch_urls tool. Parses arguments, launches headless Chromium browser (or visible if debug), fetches content from multiple URLs in parallel using Playwright pages, extracts/processes with WebContentProcessor, combines results with section markers, returns as text content.

  export async function fetchUrls(args: any) {
    const urls = (args?.urls as string[]) || [];
    if (!urls || !Array.isArray(urls) || urls.length === 0) {
      throw new Error("URLs parameter is required and must be a non-empty array");
    }
  
    const options: FetchOptions = {
      timeout: Number(args?.timeout) || 30000,
      waitUntil: String(args?.waitUntil || "load") as 'load' | 'domcontentloaded' | 'networkidle' | 'commit',
      extractContent: args?.extractContent !== false,
      maxLength: Number(args?.maxLength) || 0,
      returnHtml: args?.returnHtml === true,
      waitForNavigation: args?.waitForNavigation === true,
      navigationTimeout: Number(args?.navigationTimeout) || 10000,
      disableMedia: args?.disableMedia !== false,
      debug: args?.debug
    };
  
    // 确定是否启用调试模式（优先使用参数指定的值，否则使用命令行标志）
    const useDebugMode = options.debug !== undefined ? options.debug : isDebugMode;
    
    if (useDebugMode) {
      console.log(`[Debug] Debug mode enabled for URLs: ${urls.join(', ')}`);
    }
  
    let browser = null;
    try {
      browser = await chromium.launch({ headless: !useDebugMode });
      const context = await browser.newContext({
        javaScriptEnabled: true,
        ignoreHTTPSErrors: true,
        userAgent: 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36'
      });
  
      await context.route('**/*', async (route) => {
        const resourceType = route.request().resourceType();
        if (options.disableMedia && ['image', 'stylesheet', 'font', 'media'].includes(resourceType)) {
          await route.abort();
        } else {
          await route.continue();
        }
      });
  
      const processor = new WebContentProcessor(options, '[FetchURLs]');
      
      const results = await Promise.all(
        urls.map(async (url, index) => {
          const page = await context.newPage();
          try {
            const result = await processor.processPageContent(page, url);
            return { index, ...result } as FetchResult;
          } finally {
            if (!useDebugMode) {
              await page.close().catch(e => console.error(`[Error] Failed to close page: ${e.message}`));
            } else {
              console.log(`[Debug] Page kept open for debugging. URL: ${url}`);
            }
          }
        })
      );
  
      results.sort((a, b) => (a.index || 0) - (b.index || 0));
      const combinedResults = results
        .map((result, i) => `[webpage ${i + 1} begin]\n${result.content}\n[webpage ${i + 1} end]`)
        .join('\n\n');
  
      return {
        content: [{ type: "text", text: combinedResults }]
      };
    } finally {
      if (!useDebugMode) {
        if (browser) await browser.close().catch(e => console.error(`[Error] Failed to close browser: ${e.message}`));
      } else {
        console.log(`[Debug] Browser kept open for debugging. URLs: ${urls.join(', ')}`);
      }
    }
  }

• src/tools/fetchUrls.ts:11-72 (schema)

  Tool definition object for 'fetch_urls' including name, description, and detailed inputSchema defining parameters like urls (required), timeout, waitUntil, extractContent, etc.

  export const fetchUrlsTool = {
    name: "fetch_urls",
    description: "Retrieve web page content from multiple specified URLs",
    inputSchema: {
      type: "object",
      properties: {
        urls: {
          type: "array",
          items: {
            type: "string",
          },
          description: "Array of URLs to fetch",
        },
        timeout: {
          type: "number",
          description:
            "Page loading timeout in milliseconds, default is 30000 (30 seconds)",
        },
        waitUntil: {
          type: "string",
          description:
            "Specifies when navigation is considered complete, options: 'load', 'domcontentloaded', 'networkidle', 'commit', default is 'load'",
        },
        extractContent: {
          type: "boolean",
          description:
            "Whether to intelligently extract the main content, default is true",
        },
        maxLength: {
          type: "number",
          description:
            "Maximum length of returned content (in characters), default is no limit",
        },
        returnHtml: {
          type: "boolean",
          description:
            "Whether to return HTML content instead of Markdown, default is false",
        },
        waitForNavigation: {
          type: "boolean",
          description:
            "Whether to wait for additional navigation after initial page load (useful for sites with anti-bot verification), default is false",
        },
        navigationTimeout: {
          type: "number",
          description:
            "Maximum time to wait for additional navigation in milliseconds, default is 10000 (10 seconds)",
        },
        disableMedia: {
          type: "boolean",
          description:
            "Whether to disable media resources (images, stylesheets, fonts, media), default is true",
        },
        debug: {
          type: "boolean",
          description:
            "Whether to enable debug mode (showing browser window), overrides the --debug command line flag if specified",
        },
      },
      required: ["urls"],
    }
  };

• src/tools/index.ts:11-14 (registration)

  Maps tool names to their handler functions, registering 'fetch_urls' to the fetchUrls implementation.

  export const toolHandlers = {
    [fetchUrlTool.name]: fetchUrl,
    [fetchUrlsTool.name]: fetchUrls
  };

• src/tools/index.ts:5-8 (registration)

  Array exporting tool definitions, including fetchUrlsTool for registration in the MCP tools list.

  export const tools = [
    fetchUrlTool,
    fetchUrlsTool
  ];