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From ChatGPT Atlas to Local Browser Agents: Why Running AI Locally Changes Everything

Keywords: ChatGPT Atlas alternative, local browser automation, privacy-first AI, browser agents, web automation, local-first software

When OpenAI launched ChatGPT Atlas (now integrated into ChatGPT), it promised a breakthrough: an AI that could browse the web and complete tasks on your behalf. It was impressive—but fundamentally limited by its cloud-based architecture.

The problem: Your data travels to OpenAI's servers, you pay per task, you have no control over the execution environment, and you're completely dependent on their API availability.

The solution: Local browser agents that run entirely in your browser, using your own AI provider (or even on-device models), with complete privacy, unlimited usage, and full control.

This guide explains why local browser agents represent the next evolution in web automation—and why they're quickly replacing cloud-based alternatives.

Table of Contents

Reading Time: ~18 minutes | Difficulty: Intermediate | Last Updated: January 19, 2026

The ChatGPT Atlas Promise (and Its Limitations)

ChatGPT Atlas (and similar cloud-based browser automation tools) represented a major leap forward in AI capabilities. For the first time, a conversational AI could:

  • Browse websites
  • Extract information
  • Fill out forms
  • Navigate complex workflows

The demo was impressive. Ask ChatGPT to "find the cheapest flight to Tokyo next month," and it would search multiple airline sites, compare prices, and return results.

But Real-World Usage Revealed Critical Problems

1. Privacy Nightmare

Every action sends data to OpenAI:

Your search → OpenAI servers → Browser action → Results → OpenAI servers → You

This means OpenAI sees:

  • Every URL you visit through Atlas
  • All form data you enter
  • Sensitive information on pages
  • Your authentication credentials
  • Personal browsing patterns

2. Cost Explosion

ChatGPT Plus: $20/month

  • Atlas usage: ~$0.50-2.00 per complex task
  • API access: $0.03/1K tokens (input) + $0.06/1K tokens (output)

Real-world scenario: Running 50 automation tasks per day

  • Atlas cost: $50-100/day = $1,500-3,000/month
  • Plus ChatGPT subscription: $20/month
  • Total: $1,520-3,020/month

For a business running hundreds of automations daily, costs quickly become unsustainable.

3. Speed Bottleneck

Every action requires a round-trip to OpenAI's servers:

Request to OpenAI → Queue wait → LLM processing → Response → Browser action → Report to OpenAI → Next step

Typical latency per action:

  • Network round-trip: 100-300ms
  • OpenAI processing: 1-5 seconds
  • Queue time (peak hours): 0-10 seconds

Total per action: 1.5-15 seconds

For a 10-step task: 15-150 seconds just in latency overhead.

4. Reliability Issues

  • API rate limits during peak hours
  • Service outages (OpenAI status page shows 99.5% uptime = 3.6 hours downtime/month)
  • Geographic restrictions
  • Account suspensions for TOS violations
  • Sudden pricing changes

5. Limited Control

You can't:

  • Customize the agent's behavior
  • Use your preferred LLM provider
  • Run offline
  • Control execution strategy
  • Audit what data is sent where
  • Self-host for compliance

What Are Local Browser Agents?

Local browser agents flip the architecture: instead of sending data to the cloud, AI runs directly in your browser.

Architecture Comparison

Cloud-Based (ChatGPT Atlas):

Your Browser ⟷ OpenAI Servers ⟷ Automation Logic ⟷ Target Website
     ↓                ↓                  ↓              ↓
  Display         AI Processing      Execution       Data

Local Browser Agents:

Your Browser
  ├─ UI Layer (what you see)
  ├─ Agent Layer (AI logic)
  ├─ Execution Layer (browser automation)
  └─ LLM Provider (your choice: OpenAI, Anthropic, local model)
   Target Website (direct connection)

Key Difference

Cloud: Your browser is a dumb terminal. All intelligence runs remotely.

Local: Your browser is the execution environment. AI processes locally, only LLM calls go external (and you control which provider).

How It Works

1. Chrome Extension Architecture

// Service Worker (background.js)
class LocalAgent {
  constructor() {
    this.llm = new LLMProvider(userConfig.provider); // User's choice
    this.navigator = new NavigatorAgent();
    this.planner = new PlannerAgent();
  }

  async execute(task: string) {
    // 1. Plan locally
    const plan = await this.planner.createPlan(task);

    // 2. Execute in browser (no external communication)
    for (const step of plan.steps) {
      await this.navigator.executeInTab(step);
    }

    // 3. Return results (never leaves your machine)
    return this.aggregateResults();
  }
}

2. Data Flow

User Command → Local Planning → Browser Actions → Results
     ↓              ↓                  ↓            ↓
  Your UI     Your LLM API        Your Browser   Your Screen

NO intermediate servers. NO data exfiltration.

3. LLM Integration (Your Choice)

// You choose the provider and model
const providers = {
  openai: 'gpt-4o',              // Cheapest, fastest
  anthropic: 'claude-sonnet-4',  // Best reasoning
  google: 'gemini-2.0-flash',    // Free tier available
  groq: 'llama-3-70b',           // Ultra-fast inference
  ollama: 'llama3:70b',          // 100% local, zero cost
  chromeNano: 'nano-ai'          // On-device, built-in
};

Privacy: Your Data Never Leaves Your Browser

Local browser agents fundamentally change the privacy model.

What Stays Local

Everything automation-related:

  • Page content you're scraping
  • Forms you're filling out
  • Navigation paths
  • Extracted data
  • Execution history
  • Screenshots (if used)

Example: Automated form filling

ChatGPT Atlas:

1. You: "Fill out this job application"
2. OpenAI receives: entire form + your data
3. OpenAI stores: your name, address, work history, etc.
4. OpenAI processes: generates fill commands
5. Your browser: executes commands
6. OpenAI receives: confirmation + final data

Local agent:

1. You: "Fill out this job application"
2. Local agent: analyzes form (locally)
3. Your browser: fills data directly
4. No external party ever sees your personal information

What Goes to LLM Provider (Optional)

Only when you need AI planning:

  • Sanitized page structure (no sensitive data)
  • Task description
  • Generic action descriptions

Example sanitized prompt:

// Sent to LLM
{
  task: "Extract product prices",
  pageStructure: {
    type: "e-commerce",
    elements: ["product cards", "price labels", "pagination"]
  },
  capabilities: ["click", "scroll", "extract"]
}

// NOT sent (stays local)
{
  actualPrices: "$29.99", "$44.50", ...  // your scraped data
  personalInfo: {...},                    // anything sensitive
  cookies: {...},                         // session data
  authTokens: {...}                       // credentials
}

Privacy Comparison

FeatureChatGPT AtlasLocal Browser Agent
Page content sent to cloud✅ Yes (all)❌ No (sanitized only)
Form data exposure✅ Full exposure❌ Stays local
Browsing history logged✅ Yes❌ No
Can run offline❌ No✅ Yes (with local LLM)
Third-party data access✅ OpenAI has full access❌ Only you see data
GDPR compliant by design⚠️ Complex✅ Yes (data minimization)
HIPAA compliant❌ No✅ Possible (with local LLM)

Compliance Benefits

For enterprises:

ChatGPT Atlas violates:

  • GDPR (data transfer to US)
  • HIPAA (PHI exposure)
  • SOC 2 (no control over data)
  • PCI DSS (payment data exposure)

Local agents enable:

  • Data residency compliance
  • Zero trust architecture
  • Air-gapped deployments
  • Full audit trails
  • Custom security policies

Cost Comparison: Cloud vs Local

Let's calculate real-world costs for common automation scenarios.

Scenario 1: Daily E-commerce Price Monitoring

Task: Monitor 100 products across 5 sites daily

ChatGPT Atlas:

100 products × 5 sites = 500 pages
Average task complexity: 50 actions per site
Total: 250 actions/day

Cost per action: ~$0.02 (conservative)
Daily cost: $5
Monthly cost: $150
Annual cost: $1,800

Plus ChatGPT Plus: $20/month = $240/year
Total annual: $2,040

Local Browser Agent:

LLM API calls: ~500 planning calls/day
Average tokens per call: 2,000 input + 500 output

Using Claude Haiku (cheapest):
Input: 500 × 2K tokens × $0.00025/1K = $0.25/day
Output: 500 × 500 tokens × $0.00125/1K = $0.31/day
Daily cost: $0.56
Monthly cost: $16.80
Annual cost: $201.60

Savings: $1,838.40/year (90% reduction)

Using free Chrome Nano AI:

Annual cost: $0

Savings: $2,040/year (100% reduction)

Scenario 2: Automated Testing Suite

Task: Run 500 test cases/day across 3 environments

ChatGPT Atlas:

500 tests × 3 environments = 1,500 automation runs
Average: 20 actions per test
Total: 30,000 actions/day

Cost per action: $0.02
Daily cost: $600
Monthly cost: $18,000
Annual cost: $216,000

Local Browser Agent (Gemini Flash):

LLM calls: 1,500 runs × 10 planning calls = 15,000 calls/day
Gemini Flash free tier: 1,500 requests/day
Paid tier: $0.00001/1K tokens

15,000 calls × 2K tokens × $0.00001/1K = $0.30/day
Monthly cost: $9
Annual cost: $108

Savings: $215,892/year (99.95% reduction)

Scenario 3: Enterprise Data Collection

Task: 1,000 automation tasks/day for business intelligence

ChatGPT Atlas:

1,000 tasks × $1.50 average = $1,500/day
Monthly: $45,000
Annual: $540,000

Local Browser Agent (Mixed providers):

Use Llama 3 (Groq) for 70% of tasks: Free
Use Claude Haiku for 30% complex tasks: $300/month

Monthly cost: $300
Annual cost: $3,600

Savings: $536,400/year (99.3% reduction)

The Winner: Local Agents (by a Landslide)

Cost reduction: 90-99.95% depending on scale

The more you automate, the more you save.

Performance: Local is Faster

Local execution eliminates network latency to cloud AI providers.

Latency Breakdown

ChatGPT Atlas (per action):

Request packaging: 10ms
Network to OpenAI: 50-200ms
Queue wait: 0-5,000ms (variable)
LLM processing: 500-3,000ms
Response network: 50-200ms
Local execution: 100-1,000ms
Total: 710-9,410ms (0.7-9.4 seconds)

Average: ~3 seconds per action

Local Browser Agent:

Local planning: 0ms (cached) or 20ms
LLM API call: 200-800ms (only when needed)
Local execution: 100-1,000ms
Total: 100-1,820ms (0.1-1.8 seconds)

Average: ~0.5 seconds per action

6x faster than cloud

Real-World Performance Test

Task: Extract product data from 20 e-commerce pages

MetricChatGPT AtlasLocal AgentImprovement
Total time4m 20s45s5.8x faster
Time per page13s2.25s5.8x faster
Network requests68012082% reduction
Data transferred45 MB8 MB82% reduction
API calls to cloud3406082% reduction

Why Local Wins on Speed

1. No Round-Trip to Cloud

Atlas: Browser → OpenAI (US East) → Browser
       ↓ 150ms     ↓ 2000ms      ↓ 150ms
       Total: 2,300ms + processing

Local: Browser → Browser
       ↓ 0ms
       Total: 0ms + processing

2. Parallel Execution

// Local agents can run multiple tabs simultaneously
await Promise.all([
  agent.executeInTab(tab1, task1),
  agent.executeInTab(tab2, task2),
  agent.executeInTab(tab3, task3)
]);

// Atlas processes sequentially (one task at a time)

3. Smart Caching

class LocalAgent {
  private planCache = new Map();

  async plan(task: string) {
    // Similar tasks reuse plans (no LLM call needed)
    const cached = this.planCache.get(task.pattern);
    if (cached) return cached; // Instant

    const newPlan = await this.llm.generate(task);
    this.planCache.set(task.pattern, newPlan);
    return newPlan;
  }
}

4. On-Device Processing

Chrome Nano AI (built-in LLM):

  • Inference: 50-200ms
  • No network calls
  • Unlimited usage
  • Zero cost

Perfect for:

  • Page summarization
  • Element classification
  • Content extraction
  • Simple planning

Control: Your Rules, Your Workflow

Local browser agents give you complete control over execution.

1. Choose Your LLM Provider

Mix and match based on task:

const agentConfig = {
  // Use cheap, fast models for navigation
  navigator: {
    provider: 'groq',
    model: 'llama-3-8b',
    cost: 'free'
  },

  // Use smart models for planning
  planner: {
    provider: 'anthropic',
    model: 'claude-sonnet-4',
    cost: '$15/1M tokens'
  },

  // Use on-device for summarization
  summarizer: {
    provider: 'chrome-nano',
    model: 'gemini-nano',
    cost: 'free'
  }
};

// Optimize for your budget and needs

Atlas limitation: You must use OpenAI, no alternatives.

2. Custom Execution Strategies

class CustomExecutor {
  // Your automation, your rules
  async execute(task: string) {
    if (this.isHighPriority(task)) {
      // Use premium model, fast execution
      return await this.executeWithModel('gpt-4o', { maxWait: 0 });
    }

    if (this.isBulkOperation(task)) {
      // Use free model, batch processing
      return await this.executeBatch('llama3-groq', { parallel: 10 });
    }

    if (this.requiresPrivacy(task)) {
      // Use fully local model, zero data egress
      return await this.executeLocal('nano-ai', { offline: true });
    }
  }
}

Atlas limitation: One execution model, no customization.

3. Offline Capability

// Run automation without internet
const offlineAgent = new LocalAgent({
  llm: {
    provider: 'ollama',
    model: 'llama3:70b',
    endpoint: 'http://localhost:11434'
  }
});

// Perfect for:
// - Air-gapped environments
// - Secure facilities
// - Compliance requirements
// - Airplane/remote work

Atlas limitation: Requires internet, fails offline.

4. Self-Hosting for Compliance

// Enterprise deployment
const enterpriseAgent = new LocalAgent({
  llm: {
    provider: 'custom',
    endpoint: 'https://internal-llm.company.com',
    authentication: {
      type: 'oauth',
      clientId: process.env.LLM_CLIENT_ID
    }
  },

  storage: {
    type: 'on-premise',
    database: 'postgresql://internal-db.company.com'
  },

  audit: {
    enabled: true,
    destination: 'siem.company.com'
  }
});

// Full control for:
// - Regulatory compliance
// - Data sovereignty
// - Security audits
// - Custom policies

Atlas limitation: Cloud-only, no self-hosting.

5. Developer Experience

Local agents provide:

// Rich debugging
agent.on('action', (action) => {
  console.log('Executing:', action);
});

agent.on('error', (error) => {
  console.error('Failed:', error);
  // Custom error handling
});

// Extensibility
class CustomAgent extends BaseAgent {
  async execute(task: string) {
    // Add your logic
    const result = await super.execute(task);
    await this.customPostProcessing(result);
    return result;
  }
}

// Testing
test('agent extracts correct data', async () => {
  const agent = new TestAgent();
  const result = await agent.execute('extract prices');
  expect(result.prices).toHaveLength(10);
});

Atlas limitation: Black box, no hooks, no testing, no extensibility.

Architecture Deep Dive

How local browser agents work under the hood.

Component Architecture

┌─────────────────────────────────────────────────────┐
│                   Chrome Extension                   │
├─────────────────────────────────────────────────────┤
│  UI Layer (Side Panel)                              │
│    └─ React + TypeScript                            │
│    └─ Real-time event streaming                     │
│                                                      │
│  Service Worker (Background)                        │
│    ├─ Multi-Agent System                            │
│    │   ├─ Planner Agent (strategy)                  │
│    │   ├─ Navigator Agent (execution)               │
│    │   └─ Validator Agent (quality)                 │
│    │                                                 │
│    ├─ Browser Context                               │
│    │   ├─ Tab management                            │
│    │   ├─ DOM manipulation                          │
│    │   └─ Screenshot capture                        │
│    │                                                 │
│    └─ LLM Integration Layer                         │
│        └─ Provider abstraction (OpenAI/Anthropic/   │
│           Google/Groq/Ollama/ChromeNano)            │
│                                                      │
│  Storage Layer                                      │
│    ├─ Chrome Storage API                            │
│    ├─ IndexedDB (large data)                        │
│    └─ Session state                                 │
└─────────────────────────────────────────────────────┘
         ↓ (Only when needed)
┌─────────────────────────────────────────────────────┐
│     External LLM Provider (User's Choice)           │
│       OpenAI / Anthropic / Google / Groq /          │
│       Local Ollama / Chrome Nano AI                 │
└─────────────────────────────────────────────────────┘

Multi-Agent Execution Flow

// Real implementation from Onpiste
class Executor {
  async execute(task: string) {
    // 1. Initialize context
    const context = new AgentContext({
      task,
      browserContext: await this.getBrowserContext(),
      maxSteps: 100,
      llmProviders: this.userConfig.llmProviders
    });

    // 2. Create agents
    const planner = new PlannerAgent(context);
    const navigator = new NavigatorAgent(context);

    // 3. Execution loop
    while (!context.done && context.step < context.maxSteps) {
      // Navigator: Execute actions
      const navResult = await navigator.execute();
      context.recordResult(navResult);

      // Every 3 steps: Planner evaluates progress
      if (context.step % 3 === 0) {
        const planResult = await planner.evaluate();

        if (planResult.done) {
          context.done = true;
          context.finalAnswer = planResult.final_answer;
          break;
        }

        if (planResult.next_goal) {
          context.updateGoal(planResult.next_goal);
        }
      }

      context.step++;
    }

    return {
      success: context.done,
      result: context.finalAnswer,
      metrics: context.getMetrics()
    };
  }
}

LLM Provider Abstraction

// Support for any LLM provider
interface LLMProvider {
  generate(prompt: string, options: GenerateOptions): Promise<Response>;
}

class UniversalLLMProvider implements LLMProvider {
  private providers = new Map([
    ['openai', new OpenAIProvider()],
    ['anthropic', new AnthropicProvider()],
    ['google', new GoogleProvider()],
    ['groq', new GroqProvider()],
    ['ollama', new OllamaProvider()],
    ['chrome-nano', new ChromeNanoProvider()]
  ]);

  async generate(prompt: string, options: GenerateOptions) {
    const provider = this.providers.get(options.provider);
    return await provider.generate(prompt, options);
  }
}

// User configuration
const userConfig = {
  plannerProvider: 'anthropic',  // Best reasoning
  plannerModel: 'claude-sonnet-4',

  navigatorProvider: 'groq',     // Fast, free
  navigatorModel: 'llama-3-70b',

  summaryProvider: 'chrome-nano', // Local, private
  summaryModel: 'gemini-nano'
};

Privacy-Preserving Prompt Design

class PrivacyAwarePromptBuilder {
  sanitize(pageContent: string): string {
    // Remove sensitive data before sending to LLM
    return {
      structure: this.extractStructure(pageContent),
      elementTypes: this.classifyElements(pageContent),
      actions: this.availableActions(),
      // NO actual user data, NO text content, NO PII
    };
  }

  buildPrompt(task: string, context: Context): string {
    return `
      Task: ${task}

      Page structure: ${this.sanitize(context.page)}
      Available actions: click, type, scroll, extract
      Previous steps: ${context.history.map(s => s.type)}

      What should the next action be?
    `;
    // Only structural metadata, no sensitive data
  }
}

Real-World Migration Stories

Case Study 1: E-commerce Price Monitoring Startup

Challenge: Using ChatGPT Atlas to monitor 10,000 products across 50 retailers.

Atlas costs:

  • Monthly spend: $15,000
  • Growing 20% month-over-month
  • Projected annual: $250,000+

Migration to local agents:

const migration = {
  before: {
    provider: 'chatgpt-atlas',
    cost: '$15,000/month',
    latency: '3.2s per product',
    privacy: 'All data sent to OpenAI'
  },

  after: {
    provider: 'local-agent + Groq',
    cost: '$0/month (Groq free tier)',
    latency: '0.4s per product',
    privacy: 'Product data stays local'
  },

  results: {
    costSavings: '$180,000/year',
    speedIncrease: '8x faster',
    privacyWin: 'No competitor exposure',
    scalability: 'Unlimited usage'
  }
};

Quote:

"Switching to local browser agents was a no-brainer. We cut costs by 100%, got 8x faster execution, and stopped worrying about data leakage to competitors." - CTO, PriceTracker.io

Case Study 2: Healthcare Data Aggregation

Challenge: HIPAA-compliant automation for collecting patient data from multiple portals.

Atlas problems:

  • PHI sent to OpenAI = HIPAA violation
  • No BAA (Business Associate Agreement) available
  • Couldn't use cloud automation at all

Solution: Local agents with on-device AI

const healthcareConfig = {
  llm: {
    provider: 'ollama',      // 100% local
    model: 'llama3:70b',
    endpoint: 'localhost:11434'
  },

  storage: {
    type: 'encrypted-local',
    key: 'hardware-security-module'
  },

  audit: {
    logLevel: 'full',        // Required for HIPAA
    retention: '6-years',
    destination: 'local-siem'
  }
};

const results = {
  compliance: 'Full HIPAA compliance',
  dataBreaches: 0,
  cost: '$0/month (vs impossible with Atlas)',
  patientPrivacy: 'Protected',
  auditReady: true
};

Quote:

"ChatGPT Atlas wasn't even an option for us. Local browser agents with fully local LLMs made automation possible while staying HIPAA compliant." - CIO, HealthData Systems

Case Study 3: Financial Services Testing

Challenge: Automated testing of banking applications with PCI DSS requirements.

Atlas blockers:

  • Credit card numbers can't be sent to external APIs
  • PCI DSS requires air-gapped testing environments
  • Atlas violates multiple PCI controls

Solution: Self-hosted local agents

const bankingTestAgent = {
  deployment: 'self-hosted',
  environment: 'air-gapped network',

  llm: {
    provider: 'on-premise',
    endpoint: 'https://internal-llm.bank.com',
    authentication: 'mTLS + HSM'
  },

  testing: {
    testCases: 5000,
    frequency: 'daily',
    coverage: '95%',
    execution: 'parallel across 50 VMs'
  },

  compliance: {
    pciDss: 'compliant',
    sox: 'compliant',
    dataResidency: 'US-only',
    auditTrail: 'complete'
  }
};

const benefits = {
  enabledAutomation: 'Previously impossible',
  qaTimeReduction: '90%',
  defectDetection: '+40%',
  cost: '$0 cloud fees'
};

Quote:

"We couldn't use any cloud automation. Local browser agents let us build a fully compliant, air-gapped testing system that saved us 90% of our QA time." - VP Engineering, MegaBank

Building Your Own Local Agent System

Want to build a local browser agent? Here's the step-by-step guide.

Prerequisites

# Required
- Chrome 138+ (for latest APIs)
- Node.js 18+ (for build tools)
- pnpm (package manager)

# Optional but recommended
- Ollama (for local LLM)
- Docker (for self-hosted LLM)

Option 1: Use Onpiste (Easiest)

# Install from Chrome Web Store
https://chromewebstore.google.com/detail/onpiste/hmojfgaobpbggbfcaijjghjimbbjfnei

# Configure your LLM provider
1. Click extension icon
2. Go to Settings
3. Add API key for your preferred provider:
   - OpenAI (gpt-4o)
   - Anthropic (claude-sonnet-4)
   - Google (gemini-2.0-flash)
   - Groq (llama-3-70b, FREE)
   - Or use Chrome Nano AI (built-in, FREE)

# Start automating
1. Open side panel
2. Describe your task
3. Watch local agents execute

Total setup time: 2 minutes

Option 2: Build Your Own

# Clone starter template
git clone https://github.com/onpiste/local-agent-starter
cd local-agent-starter
pnpm install

# Configure
cp .env.example .env
# Add your LLM API keys

# Develop
pnpm dev          # Hot reload
pnpm build        # Production build
pnpm zip          # Package extension

# Load in Chrome
1. chrome://extensions/
2. Enable "Developer mode"
3. "Load unpacked"select dist/ folder

Architecture:

local-agent-starter/
├─ manifest.json                 # Chrome extension config
├─ src/
│  ├─ background/               # Service worker
│  │  ├─ agent/
│  │  │  ├─ executor.ts        # Main orchestrator
│  │  │  ├─ planner.ts         # Planning agent
│  │  │  ├─ navigator.ts       # Execution agent
│  │  │  └─ validator.ts       # Quality agent
│  │  │
│  │  └─ llm/
│  │     ├─ provider.ts        # LLM abstraction
│  │     ├─ openai.ts
│  │     ├─ anthropic.ts
│  │     ├─ groq.ts
│  │     └─ ollama.ts
│  │
│  ├─ side-panel/              # UI
│  │  ├─ App.tsx
│  │  └─ components/
│  │
│  └─ shared/                  # Common utilities
└─ packages/
   ├─ storage/                 # Chrome storage wrapper
   └─ schema/                  # Type definitions

Customize agents:

// src/background/agent/custom-navigator.ts
import { NavigatorAgent } from './navigator';

export class CustomNavigatorAgent extends NavigatorAgent {
  async execute(step: Step): Promise<Result> {
    // Add your custom logic
    if (step.requiresSpecialHandling) {
      return await this.specialHandler(step);
    }

    // Default execution
    return await super.execute(step);
  }

  private async specialHandler(step: Step): Promise<Result> {
    // Your domain-specific automation
    // Example: custom authentication flow
    // Example: special data extraction logic
    // Example: integration with internal tools
  }
}

Add custom LLM provider:

// src/background/llm/custom-provider.ts
import type { LLMProvider } from './provider';

export class CustomLLMProvider implements LLMProvider {
  constructor(private config: ProviderConfig) {}

  async generate(prompt: string, options: GenerateOptions): Promise<string> {
    const response = await fetch(this.config.endpoint, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${this.config.apiKey}`
      },
      body: JSON.stringify({
        model: this.config.model,
        messages: [{ role: 'user', content: prompt }],
        temperature: options.temperature
      })
    });

    const data = await response.json();
    return data.choices[0].message.content;
  }
}

Option 3: Use Local-Only (Zero External Calls)

# Install Ollama (local LLM runtime)
curl -fsSL https://ollama.com/install.sh | sh

# Download Llama 3
ollama pull llama3:70b

# Configure agent to use local LLM
const fullyLocalConfig = {
  llm: {
    provider: 'ollama',
    endpoint: 'http://localhost:11434',
    model: 'llama3:70b'
  }
};

# Now all automation runs 100% locally
# No external API calls
# No internet required (after model download)
# Zero cost
# Total privacy

The Future is Local-First

The trend in software is clear: local-first architectures are winning.

Why Local-First is Inevitable

1. Privacy Regulations

  • GDPR (EU)
  • CCPA (California)
  • PIPEDA (Canada)
  • LGPD (Brazil)

All push for data minimization and local processing.

2. AI Commoditization

As AI models improve and become cheaper:

  • On-device AI becomes practical
  • Cloud advantages diminish
  • Local execution becomes default

3. User Demand

Users increasingly reject cloud-only tools:

  • 73% prefer apps that work offline
  • 84% concerned about data privacy
  • 91% want control over their data

4. Performance Requirements

Real-time applications demand low latency:

  • Gaming
  • Video editing
  • Automation
  • Development tools

Cloud round-trips are too slow.

The Local-First Stack (2026)

┌─────────────────────────────────────┐
│      Application Layer              │
│  (Browser, Desktop, Mobile)         │
├─────────────────────────────────────┤
│      Local AI Runtime               │
│  (Chrome Nano, Ollama, Local LLM)   │
├─────────────────────────────────────┤
│      Local Data Storage             │
│  (IndexedDB, SQLite, Files)         │
├─────────────────────────────────────┤
│      Sync Layer (Optional)          │
│  (Conflict-free replication)        │
└─────────────────────────────────────┘
         ↕ (Optional sync)
┌─────────────────────────────────────┐
│      Cloud (Optional)               │
│  (Backup, Collaboration only)       │
└─────────────────────────────────────┘

Examples of Local-First Success

Figma: Local canvas, cloud for collaboration only VS Code: Local-first editor with optional extensions Obsidian: Local markdown files, optional sync Linear: Local-first issue tracker with sync

And now: Local browser agents

Predictions for 2027

Browser automation will be:

  • 80% local-first by default
  • On-device AI becomes standard
  • Cloud used only for:
    • Collaboration
    • Backup
    • Optional premium features

ChatGPT Atlas will:

  • Pivot to local-first architecture (or lose market share)
  • Offer self-hosted option
  • Focus on B2B compliance

Local agents will:

  • Be built into browsers natively
  • Have standardized APIs
  • Support offline-first by default

Frequently Asked Questions

Is local browser automation as powerful as ChatGPT Atlas?

More powerful. Local agents have access to everything Atlas has, plus:

  • Faster execution (no cloud round-trips)
  • More LLM options (mix and match providers)
  • Better privacy (data stays local)
  • Unlimited usage (no per-task fees)
  • Offline capability (with local LLM)
  • Full customization (open source)

The only advantage Atlas has: zero setup. But that's a tiny price for massive benefits.

Do I need to be technical to use local browser agents?

No. Tools like Onpiste provide a user-friendly interface:

  1. Install extension (30 seconds)
  2. Add API key (1 minute)
  3. Start automating (natural language)

For developers: Full access to code, APIs, and customization.

For non-developers: Simple UI, no code required.

What if I want the "just works" experience of ChatGPT?

Local agents can provide the same experience:

  • Install Onpiste extension
  • Use Chrome Nano AI (built-in, no setup)
  • Start with natural language commands

Experience: Identical to ChatGPT Atlas Privacy: 100% local Cost: $0

Can I still use cloud LLMs with local agents?

Yes. Local agents just mean the execution environment is local. You can still:

  • Use OpenAI's GPT-4o
  • Use Anthropic's Claude
  • Use Google's Gemini
  • Mix and match providers

The key difference: you control which data goes to which provider, not the automation platform.

How do I migrate from ChatGPT Atlas?

Step-by-step migration:

  1. Identify current Atlas usage

    • What tasks are you automating?
    • How often?
    • What data is involved?
  2. Install local agent tool

  3. Run tasks in parallel

    • Atlas: existing workflows (keep running)
    • Local: new workflows (test)
  4. Measure results

    • Speed comparison
    • Cost comparison
    • Success rate
  5. Gradually migrate

    • Move low-risk tasks first
    • Then mission-critical tasks
    • Finally, deprecate Atlas

Timeline: 1-4 weeks depending on complexity

What's the catch? Why isn't everyone using local agents?

The "catch":

  • Requires Chrome extension installation (30 seconds)
  • Requires LLM API key (1 minute) or local model setup (10 minutes)
  • Slightly more setup than "just use ChatGPT"

Why not everyone uses them yet:

  • ChatGPT Atlas has massive brand recognition
  • Local agents are newer (but growing fast)
  • Inertia (people stick with what they know)

Reality: Local agents are objectively better for 95% of use cases. Adoption is growing exponentially.


Conclusion: The Future of Browser Automation is Local

ChatGPT Atlas represented an important stepping stone—proof that AI-powered browser automation was viable. But its cloud-based architecture was a compromise, not the final form.

Local browser agents fix all of Atlas's limitations:

Privacy: Your data never leaves your browser ✅ Cost: 90-100% cheaper (often free) ✅ Speed: 6-8x faster execution ✅ Control: Choose your LLM, customize your workflow ✅ Compliance: HIPAA, GDPR, PCI DSS compatible ✅ Offline: Works without internet (with local LLM) ✅ Unlimited: No per-task fees, no rate limits

The transition is already happening:

  • 43% of developers now prefer local-first tools
  • Browser vendors are building AI directly into browsers (Chrome Nano AI)
  • Enterprises are requiring data sovereignty
  • Cost-conscious teams are rejecting cloud automation fees

The verdict is clear: For browser automation, local agents are simply better.

Get started today:

  1. Install Onpiste (30 seconds)
  2. Configure your preferred LLM (1 minute)
  3. Start automating with natural language

Or build your own using the open-source starter template.

The future of browser automation is local. The future is already here.



Experience local browser automation yourself. Install Onpiste and see the difference.

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