Sentinel vs. Stagehand
Real-world comparison on a production automation task. Both frameworks performing an Amazon search + product extraction. Measured over 50 runs per framework.
| Metric | Sentinel | Stagehand |
|---|---|---|
| Model | Gemini 3 Flash | GPT-4o |
| Cost per run | ~$0.002 | ~$0.08 |
| Cost / 1k runs | ~$2 | ~$80 |
| Avg. latency | ~2.8s | ~4.2s |
| Self-healing | ✓ | ✗ |
| Parallel sessions | ✓ built-in | Manual |
| Shadow DOM | ✓ | Partial |
| OpenTelemetry | ✓ | ✗ |
| Prompt caching | ✓ | ✗ |
| MCP Server | ✓ | ✗ |
| CLI | ✓ | ✗ |
| Custom LLM | ✓ | Limited |
| License | MIT | MIT |
| npm installs/week | Growing | ~600k |
Extended comparison
Sentinel vs. Stagehand, BrowserUse (Python), and plain Playwright — across the metrics that matter for production use.
| Metric | Sentinel | Stagehand | BrowserUse | Playwright |
|---|---|---|---|---|
| Language | TypeScript | TypeScript | Python | TS / Python / Java |
| AI actions | ✓ | ✓ | ✓ | ✗ (manual only) |
| Cost / run | ~$0.002 | ~$0.08 | ~$0.05 | $0 |
| Self-healing | ✓ | ✗ | Partial | ✗ |
| Parallel built-in | ✓ | Manual | Manual | ✓ |
| Shadow DOM | ✓ | Partial | ✗ | ✓ |
| OpenTelemetry | ✓ | ✗ | ✗ | ✗ |
| MCP Server | ✓ | ✗ | ✗ | ✗ |
| CLI | ✓ | ✗ | ✗ | ✓ |
| Playwright compat | ✓ drop-in | Partial | ✗ | ✓ native |
| License | MIT | MIT | MIT | Apache-2.0 |
BrowserUse costs estimated from GPT-4o-mini at default settings. Plain Playwright has no AI cost but requires manual selector maintenance.
Methodology
- Task: Amazon.de — search “laptop”, extract top 3 products (name + price)
- Runs: 50 per framework, cold browser start each time
- Date: 2026-04-08
- Sentinel model: gemini-3-flash-preview
- Stagehand model: gpt-4o (default)
- Latency: wall-clock time from goto() to result
- Cost: token usage × official API pricing
// Benchmark task: "Amazon search + extract top 3 products"
// Measured over 50 runs on amazon.de, 2026-04-08
// Sentinel (Gemini 3 Flash)
const sentinel = new Sentinel({ apiKey: process.env.GEMINI_API_KEY });
await sentinel.init();
await sentinel.goto('https://amazon.de');
const result = await sentinel.run(
'Search for "laptop", extract the top 3 products with name and price'
);
// avg: 2.8s, avg cost: $0.002
// Stagehand (GPT-4o)
const stagehand = new Stagehand({ env: 'LOCAL' });
await stagehand.init();
await stagehand.page.goto('https://amazon.de');
await stagehand.act({ action: 'search for laptop' });
const data = await stagehand.extract({ ... });
// avg: 4.2s, avg cost: $0.08Prices based on official API pricing as of 2026-04-08. Stagehand results measured using Stagehand v2.x with default configuration. Sentinel results measured with locatorCache enabled (production-recommended setting).
Real-world costs are even lower
The $0.002/run baseline assumes cold LLM calls. With locatorCache and promptCache enabled, repeated runs skip the LLM entirely — reducing effective cost by 60–90%on stable pages. In a typical test suite where most pages don't change between runs, the real cost is closer to $0.0002–$0.0008/run.
Cost calculator
How much do you save per month?
Sentinel 40× cheaper than Stagehand at this volume. Based on $0.002/run (Gemini Flash) vs $0.08/run (GPT-4o) vs ~$0.05/run (BrowserUse / GPT-4o-mini est.). With locatorCache + promptCacheenabled, Sentinel's effective cost drops further on repeated tasks.