CUA — Computer Use Agent
Autonomous browser control powered by three cloud browser providers: Steel, Browser Use, and Browserbase. Each offers CDP-based headful browser sessions for Playwright/Puppeteer automation, LLM-driven visual browsing, and human-in-the-loop workflows.
Quick Start
# Environment setup
export STEEL_API_KEY="ste-..."
export BROWSERUSE_API_KEY="bu_..."
export BROWSERBASE_API_KEY="bb_live_..."
export BROWSERBASE_PROJECT_ID="446f4b4c-..."
# Daemon commands
/cua new # Create a Steel session (default provider)
/cua new --provider browserbase # Create a Browserbase session
/cua new --provider browseruse # Create a Browser Use session
/cua browse https://example.com # Navigate in active session
/cua screenshot # Capture current page
/cua status # Show session details + live view URL
/cua release # End session
/cua list # List all active sessions
Architecture
┌──────────────────────────────────────────────────────────────────┐
│ SolanaOS CUA Skill │
│ │
│ ┌──────────────┐ ┌───────────────┐ ┌───────────────────────┐ │
│ │ Steel │ │ Browser Use │ │ Browserbase │ │
│ │ Provider │ │ Provider │ │ Provider │ │
│ │ │ │ │ │ │ │
│ │ • Sessions │ │ • CDP URL │ │ • Sessions │ │
│ │ • Proxy │ │ • Cloud │ │ • Extensions │ │
│ │ • CAPTCHA │ │ • Profiles │ │ • Stealth Mode │ │
│ │ • Live View │ │ • Proxy │ │ • Proxies │ │
│ │ • Recording │ │ │ │ • Contexts │ │
│ │ • Mobile │ │ │ │ • Functions │ │
│ │ • Regions │ │ │ │ • Live View │ │
│ │ • HLS Replay │ │ │ │ • Session Recording │ │
│ └──────┬───────┘ └──────┬────────┘ └──────────┬────────────┘ │
│ │ │ │ │
│ ┌──────┴──────────────────┴───────────────────────┴───────────┐ │
│ │ CDP (Chrome DevTools Protocol) │ │
│ │ WebSocket Connection │ │
│ └──────────────────────────┬──────────────────────────────────┘ │
│ │ │
│ ┌──────────────────────────┴──────────────────────────────────┐ │
│ │ Playwright / Puppeteer / Selenium │ │
│ │ │ │
│ │ • Page navigation • Form automation │ │
│ │ • Element interaction • Screenshot capture │ │
│ │ • File download/upload • PDF generation │ │
│ │ • Network interception • Cookie management │ │
│ └──────────────────────────────────────────────────────────────┘ │
│ │
│ ┌──────────────────────────────────────────────────────────────┐ │
│ │ LLM Vision Agent (Optional) │ │
│ │ │ │
│ │ Screenshot → Vision LLM → Action Plan → Playwright Exec │ │
│ │ │ │
│ │ Supported: Claude, GPT-4o, Gemini, Llama 3.2, Qwen 2.5 VL │ │
│ └──────────────────────────────────────────────────────────────┘ │
└──────────────────────────────────────────────────────────────────┘
Provider Comparison
| Feature |
Steel |
Browser Use |
Browserbase |
| CDP WebSocket |
✅ |
✅ |
✅ |
| Playwright |
✅ |
✅ |
✅ |
| Puppeteer |
✅ |
✅ |
✅ |
| Selenium |
✅ |
❌ |
✅ |
| Live View |
✅ WebRTC |
❌ |
✅ iframe |
| Session Recording |
✅ HLS/MP4 |
❌ |
✅ rrweb |
| Proxy |
✅ Residential |
✅ |
✅ |
| CAPTCHA Solving |
✅ Auto |
❌ |
✅ Auto |
| Stealth Mode |
✅ Fingerprint |
❌ |
✅ Advanced |
| Mobile Mode |
✅ |
❌ |
✅ Viewport |
| Multi-Region |
✅ LAX/ORD/IAD |
❌ |
✅ Multiple |
| Extensions |
❌ |
❌ |
✅ |
| Contexts (persist state) |
❌ |
✅ Profiles |
✅ |
| Keep Alive |
❌ |
❌ |
✅ |
| Functions (serverless) |
❌ |
❌ |
✅ |
| Max Timeout |
24h |
N/A |
Plan-based |
| Human-in-the-loop |
✅ interactive |
❌ |
✅ interactive |
Steel Integration
Creating Sessions
// One-line Playwright connection (simplest)
browser := chromium.ConnectOverCDP("wss://connect.steel.dev?apiKey=YOUR_KEY")
// Or with full options
session := steel.Create(ctx, &steel.CreateOptions{
UseProxy: true,
SolveCaptcha: true,
Timeout: 600000, // 10 minutes
Region: "lax",
DeviceConfig: &steel.DeviceConfig{Device: "mobile"},
})
Session Lifecycle
CREATE → LIVE → [automation] → RELEASE
↓
FAILED (crash/timeout)
- Sessions auto-release after timeout (default 5 min)
- CDP inactivity timeout: 10 min without commands
- Send heartbeat every 5 min to keep alive:
page.evaluate(() => undefined)
- Always call
Release() when done
Live View & Recording
// Embed live view (read-only)
iframe := session.DebugURL + "?interactive=false"
// Embed with control (human-in-the-loop)
iframe := session.DebugURL + "?interactive=true&showControls=true"
// Get HLS recording playlist
playlist := steel.HLSPlaylist(session.ID)
// Use with hls.js or native Safari HLS
Available Regions
| Region |
Code |
Location |
| Los Angeles |
lax |
Los Angeles, USA |
| Chicago |
ord |
Chicago, USA |
| Washington DC |
iad |
Washington DC, USA |
Browserbase Integration
Creating Sessions
// Via Browserbase API
session := browserbase.CreateSession(ctx, cfg, "default")
// Returns CDP URL for Playwright connection
browser := chromium.ConnectOverCDP(session.CDPURL)
context := browser.Contexts()[0]
page := context.Pages()[0]
Features
- Stealth Mode: Automatic fingerprinting, advanced stealth (Scale plan)
- Proxies: Built-in residential proxy network
- Contexts: Persist cookies/storage across sessions
- Extensions: Load custom Chrome extensions
- Functions: Deploy automation as serverless API endpoints
- Search: Web search without browser session
- Fetch: HTTP fetch without browser session
Session Inspector
Every Browserbase session is recorded and can be inspected:
- Live browser state and interactions
- Network requests/responses
- Console output and errors
- Performance metrics
Browser Use Integration
Cloud Sessions
// Create cloud browser via API
session := browserUseProvider.CreateSession(ctx, cfg, "default")
// Returns CDP URL
// Or via CLI
browser-use cloud connect
Session Management
// List sessions
browser-use sessions
// Close specific session
browser-use --session mySession close
// Close all sessions
browser-use close --all
Daemon Commands
| Command |
Description |
/cua new [--provider steel|browserbase|browseruse] |
Create session |
/cua browse <url> |
Navigate to URL (via shell Playwright script) |
/cua screenshot |
Capture current page |
/cua status |
Show active session details |
/cua release |
End current session |
/cua release --all |
End all sessions |
/cua list |
List active sessions |
/cua live |
Get live view URL |
/cua replay <session-id> |
Get HLS replay URL |
/cua agent <objective> |
Start autonomous CUA agent |
Autonomous CUA Agent
The CUA agent combines cloud browser sessions with vision LLMs for autonomous web navigation.
Agent Loop
1. CREATE SESSION → Steel/Browserbase/BrowserUse
2. SCREENSHOT → Capture page via CDP
3. VISION ANALYSIS → Send to Claude/GPT-4o/Gemini
4. ACTION PLANNING → LLM determines next step
5. PLAYWRIGHT EXEC → Execute action via CDP
6. REPEAT → Until objective complete or max steps
7. RELEASE → Clean up session
Vision Prompt Template
You are a Computer Use Agent controlling a cloud browser via Playwright.
OBJECTIVE: {objective}
Current page screenshot is attached. Analyze the page and determine the next action.
Available actions:
- page.goto(url) — Navigate to URL
- page.click(selector) — Click element
- page.fill(selector, text) — Fill input
- page.press(selector, key) — Press key
- page.screenshot() — Capture page
- page.waitForSelector(selector) — Wait for element
- page.evaluate(js) — Run JavaScript
- DONE — Task is complete
Respond with JSON: {"action": "...", "args": {...}, "reasoning": "..."}
Environment Variables
| Variable |
Provider |
Required |
Description |
STEEL_API_KEY |
Steel |
For Steel |
Steel API key |
BROWSERUSE_API_KEY |
Browser Use |
For BU |
Browser Use cloud API key |
BROWSERBASE_API_KEY |
Browserbase |
For BB |
Browserbase API key |
BROWSERBASE_PROJECT_ID |
Browserbase |
For BB |
Browserbase project ID |
BROWSERBASE_PROXIES |
Browserbase |
No |
Enable proxy (default: true) |
BROWSERBASE_ADVANCED_STEALTH |
Browserbase |
No |
Advanced stealth mode |
BROWSERBASE_KEEP_ALIVE |
Browserbase |
No |
Keep alive after disconnect |
BROWSERBASE_SESSION_TIMEOUT |
Browserbase |
No |
Session timeout (ms) |
ANTHROPIC_API_KEY |
Vision LLM |
No |
For Claude vision agent |
OPENAI_API_KEY |
Vision LLM |
No |
For GPT-4o vision agent |
API Reference
Steel API
POST /v1/sessions Create session
GET /v1/sessions List sessions
GET /v1/sessions/:id Get session details
POST /v1/sessions/:id/release Release session
POST /v1/sessions/release Release all sessions
GET /v1/sessions/:id/screenshot Capture screenshot
GET /v1/sessions/:id/events Get replay events
GET /v1/sessions/:id/hls Get HLS playlist
WSS connect.steel.dev?apiKey=...&sessionId=... CDP WebSocket
Browserbase API
POST /v1/sessions Create session
GET /v1/sessions/:id Get session details
POST /v1/sessions/:id Close session (REQUEST_RELEASE)
GET /v1/sessions/:id/debug Get debug URLs
Browser Use API
POST /api/v2/browsers Create cloud browser
PATCH /api/v2/browsers/:id Stop browser (action: "stop")
Playwright Connection Patterns
Steel (one-liner)
import { chromium } from "playwright-core";
const browser = await chromium.connectOverCDP(
`wss://connect.steel.dev?apiKey=${process.env.STEEL_API_KEY}`
);
Steel (managed session)
import Steel from "steel-sdk";
import { chromium } from "playwright";
const client = new Steel({ steelAPIKey: process.env.STEEL_API_KEY });
const session = await client.sessions.create({
useProxy: true,
solveCaptcha: true,
});
const browser = await chromium.connectOverCDP(
`wss://connect.steel.dev?apiKey=${process.env.STEEL_API_KEY}&sessionId=${session.id}`
);
const page = browser.contexts()[0].pages()[0];
await page.goto("https://example.com");
await browser.close();
await client.sessions.release(session.id);
Browserbase
import { chromium } from "playwright-core";
import { Browserbase } from "@browserbasehq/sdk";
const bb = new Browserbase({ apiKey: process.env.BROWSERBASE_API_KEY });
const session = await bb.sessions.create();
const browser = await chromium.connectOverCDP(session.connectUrl);
const page = browser.contexts()[0].pages()[0];
await page.goto("https://example.com");
Browser Use (CDP)
import { chromium } from "playwright-core";
// After creating a session via API, connect with CDP URL
const browser = await chromium.connectOverCDP(session.cdpUrl);