crawl_url_content
Extract content from web pages by crawling URLs to retrieve text, links, and images for research and analysis.
Instructions
Crawl and extract content from a single web page
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | URL of the web page to crawl | |
| extractText | No | Extract main text content | |
| extractLinks | No | Extract all links from the page | |
| extractImages | No | Extract all images from the page | |
| maxContentLength | No | Maximum length of extracted content |
Implementation Reference
- The core handler function that executes the tool: validates URL, fetches page using axios via WebCrawlerClient, extracts content using cheerio, and returns structured data with metadata.
execute: async (args: any) => { const { url, extractText = true, extractLinks = false, extractImages = false, maxContentLength = 5000 } = args; try { const startTime = Date.now(); // 验证URL格式 try { new URL(url); } catch { return { success: false, error: 'Invalid URL format' }; } const pageData = await client.fetchPage(url); const content = client.extractContent(pageData.html, { extractText, extractLinks, extractImages, maxContentLength, maxLinks: 50, maxImages: 20 }); const crawlTime = Date.now() - startTime; return { success: true, data: { source: 'Web Crawler', url, finalUrl: pageData.url, status: pageData.status, crawlTime, content: { ...content, extractedAt: new Date().toISOString() }, metadata: { extractText, extractLinks, extractImages, contentLength: content.contentLength || 0, linksCount: content.links?.length || 0, imagesCount: content.images?.length || 0 }, timestamp: Date.now() } }; } catch (error) { return { success: false, error: `Web crawling failed: ${error instanceof Error ? error.message : String(error)}`, data: { source: 'Web Crawler', url, suggestions: [ 'Check if the URL is accessible', 'Verify the website allows crawling', 'Try again in a few moments', 'Check your internet connection' ] } }; } } - Input schema defining parameters for the tool: url (required), extractText, extractLinks, extractImages, maxContentLength.
inputSchema: { type: 'object', properties: { url: { type: 'string', description: 'URL of the web page to crawl' }, extractText: { type: 'boolean', description: 'Extract main text content', default: true }, extractLinks: { type: 'boolean', description: 'Extract all links from the page', default: false }, extractImages: { type: 'boolean', description: 'Extract all images from the page', default: false }, maxContentLength: { type: 'number', description: 'Maximum length of extracted content', default: 5000, minimum: 100, maximum: 20000 } }, required: ['url'] }, - src/tools/utility/web-crawler-tools.ts:184-289 (registration)Local registration of the 'crawl_url_content' tool within the registerWebCrawlerTools function, including name, description, schema, and handler.
registry.registerTool({ name: 'crawl_url_content', description: 'Crawl and extract content from a single web page', category: 'utility', source: 'Web Crawler', inputSchema: { type: 'object', properties: { url: { type: 'string', description: 'URL of the web page to crawl' }, extractText: { type: 'boolean', description: 'Extract main text content', default: true }, extractLinks: { type: 'boolean', description: 'Extract all links from the page', default: false }, extractImages: { type: 'boolean', description: 'Extract all images from the page', default: false }, maxContentLength: { type: 'number', description: 'Maximum length of extracted content', default: 5000, minimum: 100, maximum: 20000 } }, required: ['url'] }, execute: async (args: any) => { const { url, extractText = true, extractLinks = false, extractImages = false, maxContentLength = 5000 } = args; try { const startTime = Date.now(); // 验证URL格式 try { new URL(url); } catch { return { success: false, error: 'Invalid URL format' }; } const pageData = await client.fetchPage(url); const content = client.extractContent(pageData.html, { extractText, extractLinks, extractImages, maxContentLength, maxLinks: 50, maxImages: 20 }); const crawlTime = Date.now() - startTime; return { success: true, data: { source: 'Web Crawler', url, finalUrl: pageData.url, status: pageData.status, crawlTime, content: { ...content, extractedAt: new Date().toISOString() }, metadata: { extractText, extractLinks, extractImages, contentLength: content.contentLength || 0, linksCount: content.links?.length || 0, imagesCount: content.images?.length || 0 }, timestamp: Date.now() } }; } catch (error) { return { success: false, error: `Web crawling failed: ${error instanceof Error ? error.message : String(error)}`, data: { source: 'Web Crawler', url, suggestions: [ 'Check if the URL is accessible', 'Verify the website allows crawling', 'Try again in a few moments', 'Check your internet connection' ] } }; } } }); - src/index.ts:248-248 (registration)Top-level registration call in the main server initialization that registers the web crawler tools including 'crawl_url_content'.
registerWebCrawlerTools(this.toolRegistry); // 2 tools: crawl_url_content, batch_crawl_urls - WebCrawlerClient class providing helper methods: fetchPage (axios fetch), extractContent (cheerio parsing for title, desc, content, links, images), crawlMultiplePages.
class WebCrawlerClient { private userAgent = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36'; async fetchPage(url: string, options: any = {}) { try { const response = await axios.get(url, { timeout: options.timeout || 15000, headers: { 'User-Agent': this.userAgent, 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'Accept-Language': 'en-US,en;q=0.5', 'Accept-Encoding': 'gzip, deflate', 'Connection': 'keep-alive', 'Upgrade-Insecure-Requests': '1' }, maxRedirects: 5, validateStatus: (status) => status < 400 }); return { html: response.data, status: response.status, headers: response.headers, url: response.config.url || url }; } catch (error) { throw error; } } extractContent(html: string, options: any = {}) { const $ = cheerio.load(html); // 移除脚本和样式标签 $('script, style, nav, footer, aside, .advertisement, .ads').remove(); const result: any = { title: $('title').text().trim() || $('h1').first().text().trim() || 'No title found', description: $('meta[name="description"]').attr('content') || $('meta[property="og:description"]').attr('content') || 'No description found', keywords: $('meta[name="keywords"]').attr('content') || '', author: $('meta[name="author"]').attr('content') || $('meta[property="article:author"]').attr('content') || '', publishDate: $('meta[property="article:published_time"]').attr('content') || $('meta[name="date"]').attr('content') || '', url: $('meta[property="og:url"]').attr('content') || '', image: $('meta[property="og:image"]').attr('content') || $('img').first().attr('src') || '' }; // 提取主要内容 if (options.extractText) { // 尝试多种内容选择器 const contentSelectors = [ 'article', '.content', '.post-content', '.entry-content', '.article-content', 'main', '.main-content', '#content', '.container' ]; let mainContent = ''; for (const selector of contentSelectors) { const content = $(selector).text().trim(); if (content && content.length > mainContent.length) { mainContent = content; } } // 如果没有找到主要内容，提取body中的文本 if (!mainContent) { mainContent = $('body').text().trim(); } // 清理文本 mainContent = mainContent .replace(/\s+/g, ' ') .replace(/\n\s*\n/g, '\n') .trim(); result.content = mainContent.substring(0, options.maxContentLength || 5000); result.contentLength = mainContent.length; } // 提取链接 if (options.extractLinks) { const links: any[] = []; $('a[href]').each((_, element) => { const href = $(element).attr('href'); const text = $(element).text().trim(); if (href && text) { links.push({ url: href, text: text, isExternal: href.startsWith('http') && !href.includes(new URL(result.url || '').hostname) }); } }); result.links = links.slice(0, options.maxLinks || 50); } // 提取图片 if (options.extractImages) { const images: any[] = []; $('img[src]').each((_, element) => { const src = $(element).attr('src'); const alt = $(element).attr('alt') || ''; if (src) { images.push({ url: src, alt: alt, title: $(element).attr('title') || '' }); } }); result.images = images.slice(0, options.maxImages || 20); } return result; } async crawlMultiplePages(urls: string[], options: any = {}) { const results = []; const maxConcurrent = options.maxConcurrent || 3; for (let i = 0; i < urls.length; i += maxConcurrent) { const batch = urls.slice(i, i + maxConcurrent); const batchPromises = batch.map(async (url) => { try { const pageData = await this.fetchPage(url, options); const content = this.extractContent(pageData.html, options); return { url, success: true, data: { ...content, status: pageData.status, finalUrl: pageData.url } }; } catch (error) { return { url, success: false, error: error instanceof Error ? error.message : String(error) }; } }); const batchResults = await Promise.all(batchPromises); results.push(...batchResults); // 添加延迟以避免过于频繁的请求 if (i + maxConcurrent < urls.length) { await new Promise(resolve => setTimeout(resolve, options.delay || 1000)); } } return results; } }