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    Integration
    MCP

    MCP Server

    Give any AI agent the ability to scrape, extract, and screenshot the web. One npm package, any MCP-compatible client.

    9 Tools
    Zero Config
    Anti-Bot Bypass
    Structured Extraction

    Overview

    The AlterLab MCP server (alterlab-mcp-server on npm) implements the Model Context Protocol so that AI agents running in Claude Code, Claude Desktop, Cursor, Windsurf, Codex CLI, and Gemini CLI can scrape any website, extract structured data, take full-page screenshots, and manage authenticated sessions — all without leaving the agent environment.

    The server proxies every request through AlterLab's intelligent tier system, automatically handling JavaScript rendering, TLS fingerprinting, and anti-bot challenges. Your agent describes what it needs; AlterLab handles the complexity of actually retrieving it.

    9
    Tools exposed to your agent
    6
    Supported AI clients
    $1
    Free credits on sign-up

    Installation

    The MCP server runs as a local process. You can install it globally or let your client invoke it on-demand with npx. Node.js 18 or later is required.

    Global install (recommended for frequent use)

    Bash
    npm install -g alterlab-mcp-server

    On-demand via npx (no install needed)

    Bash
    npx -y alterlab-mcp-server

    API Key

    All tools require your AlterLab API key, passed via the ALTERLAB_API_KEY environment variable. Get your key from the Dashboard → API Keys.

    Available Tools

    The MCP server exposes 9 tools. Each tool maps directly to an AlterLab API capability. Your agent can call any of them by name once the server is connected.

    ToolDescription
    alterlab_scrapeScrape any URL and return content as markdown, plain text, HTML, or structured JSON. Supports JavaScript rendering, anti-bot bypass, and extraction profiles.
    alterlab_extractExtract structured JSON from a URL using a named profile (e.g. product, article) or a custom JSON Schema. Returns typed, validated data.
    alterlab_screenshotCapture a full-page PNG screenshot of any URL. Returns a hosted image URL. Useful for visual inspection or documentation.
    alterlab_estimate_costPre-estimate the cost of scraping a URL before making the request. Returns estimated USD cost and confidence level based on domain history.
    alterlab_check_balanceCheck the remaining credit balance on the account associated with the API key. Useful for budget-aware agents.
    alterlab_list_sessionsList all stored browser sessions on the account. Sessions hold cookies for authenticated scraping of sites that require login.
    alterlab_create_sessionStore a set of browser cookies as a named session for reuse across scrape requests. Accepts a domain, session name, and cookie dictionary.
    alterlab_validate_sessionCheck whether a stored session's cookies are still valid by making a test request to the session's domain. Returns a boolean validity status.
    alterlab_delete_sessionPermanently remove a stored session by its ID. Use after cookies have expired or the session is no longer needed.

    Claude Code

    Add the AlterLab MCP server to your Claude Code session with a single command. The server will be available to all future sessions on your machine.

    Step 1 — Register the server

    Bash
    claude mcp add alterlab -- npx -y alterlab-mcp-server

    Step 2 — Set your API key

    Bash
    export ALTERLAB_API_KEY=sk_live_your_key_here

    Add this to your shell profile (~/.bashrc or ~/.zshrc) to persist it across sessions.

    Verify the connection

    After registering, start a new Claude Code session and ask: “Use AlterLab to scrape https://example.com and summarize the content.” Claude will call alterlab_scrape automatically.

    Claude Desktop

    Add AlterLab to the mcpServers block in your Claude Desktop config file.

    Config file location

    PlatformPath
    macOS~/Library/Application Support/Claude/claude_desktop_config.json
    Windows%APPDATA%\Claude\claude_desktop_config.json

    Add to config

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    Restart required

    Quit and reopen Claude Desktop after editing the config file for the server to appear.

    Cursor

    Cursor supports MCP servers scoped to a project via a .cursor/mcp.json file in the repository root, or globally via ~/.cursor/mcp.json.

    .cursor/mcp.json (project-scoped)

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    Commit this file to your repository so all collaborators get the integration automatically. Each developer supplies their own API key via their environment.

    Use environment variables for the key

    Instead of hard-coding ALTERLAB_API_KEY in the JSON, omit the env block and export the variable in your shell profile. Cursor inherits your shell environment when launching MCP servers.

    Windsurf

    Windsurf reads MCP server configuration from a global JSON file in the Codeium directory.

    Config file location

    Bash
    ~/.codeium/windsurf/mcp_config.json

    Add to config

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    Restart Windsurf after editing

    Close and reopen Windsurf to load newly added MCP servers.

    Codex CLI

    OpenAI's Codex CLI supports MCP servers via a global config or a project-level override file.

    Global config (~/.codex/config.json)

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    Project override (.codex/mcp.json in repo root)

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    The project-level file takes precedence over the global config when both are present.

    Gemini CLI

    Google's Gemini CLI reads MCP server configuration from the settings file in the ~/.gemini directory.

    ~/.gemini/settings.json

    JSON
    {
      "mcpServers": {
        "alterlab": {
          "command": "npx",
          "args": ["-y", "alterlab-mcp-server"],
          "env": {
            "ALTERLAB_API_KEY": "sk_live_your_key_here"
          }
        }
      }
    }

    Verify available tools

    Run gemini /mcp in the CLI to list all connected MCP servers and confirm the 9 AlterLab tools are visible.

    Extraction Profiles

    When calling alterlab_extract or passing a profile to alterlab_scrape, you can specify a named profile to receive a consistent, typed JSON structure optimized for that content type. Profiles eliminate the need to write a JSON Schema for common data formats.

    ProfileBest ForKey Fields Returned
    autoAny page — AlterLab infers the best schemaVaries by content type detected
    productE-commerce product pagesname, price, currency, in_stock, images, description, rating, review_count, sku, brand
    articleBlog posts, news articlestitle, author, published_at, body_markdown, tags, summary, image_url
    job_postingJob boards, career pagestitle, company, location, remote, salary_range, description, requirements, posted_at, apply_url
    faqFAQ sections, help pagesitems[ ] with question and answer fields
    recipeCooking and food sitesname, ingredients, instructions, prep_time, cook_time, servings, nutrition, author
    eventEvent listings, ticketing pagesname, start_date, end_date, location, organizer, ticket_url, price, description

    Custom schemas

    For data that doesn't fit a built-in profile, pass a JSON Schema directly in the schema parameter of alterlab_extract. AlterLab's extraction engine will populate it from the page content.

    Authenticated Scraping

    Some sites require a logged-in browser session to return meaningful content — dashboards, order history pages, paywalled articles. AlterLab sessions let your agent store a set of cookies once and reuse them across many requests without re-authenticating each time.

    Typical agent workflow

    1. Call alterlab_list_sessions to see if a session for the target domain already exists.
    2. If no session exists, call alterlab_create_session with the domain and cookies extracted from your browser.
    3. Pass the session_id to alterlab_scrape or alterlab_extract to make authenticated requests.
    4. If a scrape fails with an authentication error, call alterlab_validate_session to check whether cookies have expired, then refresh them as needed.

    Cookie security

    Session cookies are encrypted at rest and scoped to your API key. Never pass session tokens for financial or healthcare platforms unless you own those accounts.

    Pricing

    Each tool call consumes credits based on the scraping tier required and any add-ons applied. AlterLab's tier system automatically selects the cheapest tier that can successfully retrieve the page — your agent only pays for what is needed. New accounts receive $1 in free credits with no credit card required.

    Base tier cost per request

    TierNameCostRequests per $1When used
    1Curl$0.00025,000Plain static HTML with no bot protection
    2HTTP$0.00033,333TLS fingerprinting and header challenges
    3Stealth$0.00052,000Browser fingerprint checks without full JS execution
    3.5Light JS$0.00071,428Lightweight JS rendering for simple SPAs
    4Browser$0.0011,000Full headless browser for heavy JS and anti-bot walls

    Add-on costs (applied on top of base tier)

    Add-onAdditional costDescription
    JavaScript rendering+$0.0006Full JS execution on top of an HTTP-tier request
    Residential proxy+$0.0002Routes request through a residential IP for geo-sensitive targets
    OCR extraction+$0.001Optical character recognition on image-based content

    Use alterlab_estimate_cost first

    For budget-aware agents, call alterlab_estimate_cost before scraping an unfamiliar domain. The tool returns a cost estimate and confidence level based on historical data for that domain, so your agent can decide whether to proceed.
    $1 free on sign-up
    New accounts receive $1 in credits with no credit card required. That's up to 5,000 basic scrapes or ~1,000 full browser renders to explore the platform before committing. Create a free account.
    From ScrapingBee / ScraperAPIn8n Node
    Last updated: March 2026

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