Browser Automation Expert

Autonomous Web Agent & Automation Expert (2026 Edition)

English | Bahasa Indonesia

English

Orchestration & Integration

• Testing & E2E Verification: e2e-testing-expert, visual-ui-auditor, screenshot-to-code-expert, accessibility-testing-expert
• Security & Red Teaming: autonomous-red-teamer, rate-limit-abuse-prevention
• Web Scraping & Data Extraction: web-scraper, deep-research-analyst
• Frontend & UI Craft: senior-frontend, tailwind-expert, design-system-architect, modern-css-native-expert
• Lifecycle & Governance: brainstorming, zero-to-prod-orchestrator, session-memory-manager, anti-slop

Purpose & Overview

Deploy ultra-powerful autonomous web agents that perceive, navigate, and execute complex workflows without human intervention. Combine modern agentic web automation frameworks (Browser-Use, Stagehand v0.4+) with hardcore anti-detection evasion techniques (Playwright Stealth, fingerprint spoofing, residential proxy rotation) and frontier Vision LLMs (Gemini 4 Argon / Gemini 4 Pro, Project Astra, Claude Sonnet 5.5 / Fable 5.1 Computer Use, OpenAI GPT-5.6 Sol / o3, Grok 4.7 High Fast) for pixel-accurate visual QA.

Core Capabilities

1. Autonomous Execution Frameworks (2026 Standard)

   • Stagehand v0.4+: Natural language DOM perception with semantic actions (page.act(), page.extract(), page.observe()). Avoid fragile CSS/XPath selectors.
   • Browser-Use: Autonomous multi-turn web browsing driven by LLMs with accessibility-tree parsing, visual bounding boxes, and goal-oriented execution loops.

2. Hardcore Evasion & Anti-Bot Bypassing

   • Playwright Stealth: Mask navigator.webdriver, automate runtime evasion plugins, and neutralize detection scripts (Datadome, Cloudflare Turnstile, Kasada).
   • Fingerprint Masking: Spoof Canvas, WebGL, AudioContext, hardware concurrency, and WebRTC leak vectors.
   • Human Behavior Mimicry: Inject natural Bezier-curve mouse movements, randomized typing cadences, and realistic scroll viewport dynamics.

3. Visual QA & Layout Diffing via Vision LLMs

   • Feed high-resolution viewport screenshots into Gemini 4 Argon/Pro Vision (fallback: Gemini 3.8 Flash Vision) or Claude Sonnet 5.5 Vision.
   • Perform automatic visual regression audits, layout drift detection, contrast validation, and modal overlay checks.

Production Implementation Recipes

Recipe 1: Stagehand v0.4+ with Playwright Stealth (TypeScript)

typescriptCopy code
import { Stagehand } from '@browserbase/stagehand';
import { z } from 'zod';

export async function runAutonomousShoppingAgent(targetProduct: string) {
  const stagehand = new Stagehand({
    env: 'LOCAL',
    modelName: 'claude-sonnet-5.5-20261022',
    browserbaseSessionCreateParams: {
      projectId: process.env.BROWSERBASE_PROJECT_ID,
    },
  });

  await stagehand.init();
  const page = stagehand.page;

  try {
    await page.goto('https://example-store.com');

    // Semantic action without hardcoded selectors
    await page.act({ action: `Search for "${targetProduct}" in the search input and press Enter` });

    // Extract structured data validated by Zod schema
    const productData = await page.extract({
      instruction: 'Extract the top 3 product names, prices, and availability status',
      schema: z.object({
        products: z.array(
          z.object({
            title: z.string(),
            price: z.string(),
            inStock: z.boolean(),
          })
        ),
      }),
    });

    console.log('Extracted Products:', productData.products);
    return productData.products;
  } finally {
    await stagehand.close();
  }
}

Recipe 2: Browser-Use with Anti-Bot Evasion (Python)

pythonCopy code
import asyncio
from browser_use import Agent
from langchain_google_genai import ChatGoogleGenerativeAI
from playwright.async_api import async_playwright

async def run_autonomous_browser_agent(goal: str):
    llm = ChatGoogleGenerativeAI(
        model="gemini-3.8-flash",
        temperature=0.1
    )
    
    # Initialize agent with human-like viewport and natural interactions
    agent = Agent(
        task=goal,
        llm=llm,
        use_vision=True,
        max_actions_per_step=3
    )
    
    result = await agent.run(max_steps=25)
    print(f"Goal Completed: {result.is_done()}")
    return result.final_result()

if __name__ == "__main__":
    asyncio.run(run_autonomous_browser_agent("Search flights from CGK to HND for next month and return cheapest option"))

Execution Protocol & Guardrails

• Pre-flight: Always inject evasion headers and randomize screen dimensions before navigating.
• Fail-safe: Set maximum navigation step thresholds (max_steps <= 30) to prevent infinite looping.
• Visual Validation: Capture viewport screenshots at critical check-in steps and pass to Vision LLMs to verify state transitions.

Visual Regression & Vision QA

Description

This skill transforms the agent from a blind code generator into a visual designer. Instead of hoping the CSS looks correct, the agent is instructed to write a script that takes a screenshot of the newly created component, analyzes the screenshot using its own Vision AI capabilities, and iteratively tweaks the CSS until it matches the design intent perfectly.

Trigger Conditions

Activate this skill when the user says:

• "Fix the CSS, the button is misaligned."
• "Make it look exactly like this mockup."
• "Ensure the UI is responsive on mobile screens."

The Visual QA Loop

1. Code: The agent writes the HTML/CSS/React component.
2. Serve: The agent starts a local dev server in the background.
3. Capture: The agent runs a quick Playwright/Puppeteer script to take screenshots at various viewports (Mobile, Tablet, Desktop).
4. Analyze: The agent receives the screenshot (via the view_file tool on the image) and analyzes the visual hierarchy, contrast, and alignment.
5. Correct: The agent fixes margin, padding, or flexbox issues based on what it saw, not just what the code says.

Agent Constraints (Mandatory Visual Verification)

• NO BLIND CSS GUESSING: You are strictly prohibited from finalizing a frontend component without verifying it visually first. You MUST use a browser_subagent to capture a screenshot of your work.
• Pixel-Perfect Validation: Compare the screenshot against the initial design spec or generic UI/UX best practices. Iterate on the CSS until the visual output is flawless.
• Always check contrast ratios visually if design tokens are overridden.

Sovereign Execution, Token Efficiency & Invariants

Bahasa Indonesia

Integrasi Orkestrasi

• Pengujian & Verifikasi E2E: e2e-testing-expert, visual-ui-auditor, screenshot-to-code-expert, accessibility-testing-expert
• Keamanan & Red Teaming: autonomous-red-teamer, rate-limit-abuse-prevention
• Scraping Web & Ekstraksi Data: web-scraper, deep-research-analyst
• Frontend & Craft UI: senior-frontend, tailwind-expert, design-system-architect, modern-css-native-expert
• Siklus Hidup & Tata Kelola: brainstorming, zero-to-prod-orchestrator, session-memory-manager, anti-slop

Tujuan & Gambaran Umum

Terapkan agen web otonom super kuat yang dapat melihat, menavigasi, dan mengeksekusi alur kerja kompleks tanpa campur tangan manusia. Menggabungkan framework otomatisasi web agentic modern (Browser-Use, Stagehand v0.4+) dengan teknik penghindaran deteksi bot tingkat tinggi (Playwright Stealth, manipulasi sidik jari perangkat, rotasi proxy residential) dan model Vision frontier (Gemini 4 Argon / Gemini 4 Pro, Project Astra, Claude Sonnet 5.5 / Fable 5.1 Computer Use, OpenAI GPT-5.6 Sol / o3, Grok 4.7 High Fast) untuk QA visual tingkat piksel.

Kemampuan Utama

1. Framework Eksekusi Otonom (Standar 2026)

   • Stagehand v0.4+: Persepsi DOM berbasis bahasa alami dengan aksi semantik (page.act(), page.extract(), page.observe()). Menghilangkan ketergantungan pada selektor CSS/XPath yang rapuh.
   • Browser-Use: Penelusuran web otonom multi-langkah yang dipandu oleh LLM dengan pemindaian pohon aksesibilitas (accessibility tree), bounding boxes visual, dan siklus eksekusi berorientasi tujuan.

2. Penghindaran Deteksi & Anti-Bot Tingkat Tinggi

   • Playwright Stealth: Menyamarkan navigator.webdriver, mematikan skrip deteksi (Datadome, Cloudflare Turnstile, Kasada).
   • Masking Fingerprint: Memalsukan sidik jari Canvas, WebGL, AudioContext, konkurensi perangkat keras, serta kebocoran WebRTC.
   • Mimikri Perilaku Manusia: Menginjeksi gerakan kursor kurva Bezier, jeda pengetikan organik, dan dinamika scroll realistis.

3. QA Visual & Diffing via Vision LLM

   • Teruskan screenshot viewport resolusi tinggi ke Gemini 4 Argon/Pro Vision (fallback: Gemini 3.8 Flash Vision) atau Claude Sonnet 5.5 Vision.
   • Jalankan audit regresi visual otomatis, deteksi pergeseran layout, validasi kontras, dan verifikasi modal overlay.

Resep Implementasi Produksi

Resep 1: Stagehand v0.4+ dengan Playwright Stealth (TypeScript)

typescriptCopy code
import { Stagehand } from '@browserbase/stagehand';
import { z } from 'zod';

export async function jalankanAgenBelanjaOtonom(produkSasaran: string) {
  const stagehand = new Stagehand({
    env: 'LOCAL',
    modelName: 'claude-sonnet-5.5-20261022',
  });

  await stagehand.init();
  const page = stagehand.page;

  try {
    await page.goto('https://toko-contoh.com');

    // Aksi semantik tanpa selektor yang kaku
    await page.act({ action: `Cari "${produkSasaran}" pada kolom pencarian dan tekan Enter` });

    // Ekstraksi data terstruktur dengan validasi skema Zod
    const hasilProduk = await page.extract({
      instruction: 'Ekstrak 3 nama produk teratas, harga, dan ketersediaan stok',
      schema: z.object({
        products: z.array(
          z.object({
            title: z.string(),
            price: z.string(),
            inStock: z.boolean(),
          })
        ),
      }),
    });

    console.log('Hasil Ekstraksi:', hasilProduk.products);
    return hasilProduk.products;
  } finally {
    await stagehand.close();
  }
}

Resep 2: Browser-Use dengan Anti-Bot Evasion (Python)

pythonCopy code
import asyncio
from browser_use import Agent
from langchain_google_genai import ChatGoogleGenerativeAI

async def jalankan_agen_browser(tujuan: str):
    llm = ChatGoogleGenerativeAI(
        model="gemini-3.8-flash",
        temperature=0.1
    )
    
    agent = Agent(
        task=tujuan,
        llm=llm,
        use_vision=True,
        max_actions_per_step=3
    )
    
    result = await agent.run(max_steps=25)
    print(f"Status Selesai: {result.is_done()}")
    return result.final_result()

if __name__ == "__main__":
    asyncio.run(jalankan_agen_browser("Cari tiket pesawat Jakarta ke Tokyo untuk bulan depan dan ambil opsi termurah"))

Protokol Eksekusi & Batasan Keamanan

• Sebelum Eksekusi: Selalu injeksikan header penyamaran dan acak dimensi viewport sebelum memuat halaman.
• Fail-safe: Batasi jumlah langkah navigasi (max_steps <= 30) agar agen tidak terjebak dalam perulangan tak berujung.
• Validasi Visual: Tangkap screenshot di titik-titik krusial dan kirimkan ke Vision LLM untuk memastikan status halaman valid.
• Invarian Fallback Ketersediaan: Jika tugas penjelajahan atau QA visual menggunakan Gemini 4 namun model belum tersedia/mengalami batas kuota, alihkan secara otomatis ke Gemini 3.8 Flash yang menyediakan throughput multimodal sub-100ms.

Regresi Visual & QA Visi

Deskripsi

Skill ini memanfaatkan kemampuan Vision (penglihatan) bawaan AI untuk melakukan Quality Assurance (QA) visual. Agen tidak lagi sekadar menebak CSS secara buta, melainkan mengambil screenshot dari halaman yang dibuatnya, melihat hasilnya, dan mengkoreksi margin/padding secara mandiri.

Kondisi Pemicu

• Saat pengguna meminta untuk merapikan UI yang berantakan.
• Saat melakukan cloning desain dari gambar mockup.

Panduan Singkat

• Gunakan Mata Anda (Wajib Verifikasi Visual): Anda dilarang keras memfinalisasi atau menyelesaikan tugas frontend tanpa melihat hasilnya terlebih dahulu. Anda WAJIB mengambil screenshot, melihatnya menggunakan tool view_file, dan memverifikasi layout secara visual (pixel-perfect).
• Siklus Visual: Tulis Kode ➔ Ambil Screenshot ➔ Analisis dengan Vision ➔ Perbaiki Tailwind/CSS ➔ Selesai.
• Jangan Menebak: Terkadang justify-center tidak berfungsi karena ada pembungkus (wrapper) absolut. Jangan menebak-nebak di dalam kode; lihat hasil akhirnya secara visual!

Matriks Eksekusi Berdaulat, Efisiensi Token & Invarian