The Transparent FingerprintJS Alternative & Bot Detection API.

// Node.js (Express / Next.js Route Handler)
import { BotRefundClient } from "@botrefund/sdk";

const botRefund = new BotRefundClient({ 
  apiKey: process.env.BOTREFUND_SECRET_KEY 
});

app.post("/api/auth/register", async (req, res) => {
  const { deviceToken, email } = req.body;

  // Verify token and retrieve detailed device signals
  const result = await botRefund.verify(deviceToken);

  if (result.is_bot || result.bot_score > 0.65) {
    return res.status(403).json({ error: "Automated access blocked" });
  }

  if (result.is_returning) {
    // Prevent multi-accounting and free trial token churning
    console.warn("Returning device detected: " + result.visitor_id);
    return res.status(409).json({ error: "Free trial already claimed" });
  }

  // Proceed to create human user account
  return createUser({ email, visitorId: result.visitor_id });
});

# Python (FastAPI / Flask)
import httpx, os

async def verify_visitor(device_token: str):
    async with httpx.AsyncClient() as client:
        resp = await client.post(
            "https://api.botrefund.com/v1/verify",
            json={"request_id": device_token},
            headers={"Authorization": f"Bearer {os.environ['BOTREFUND_API_KEY']}"}
        )
        data = resp.json()

    # Check bot flags and multi-accounting status
    if data.get("is_bot") or data.get("bot_score", 0) > 0.65:
        raise HTTPException(status_code=403, detail="Bot detected")
        
    if data.get("is_returning"):
        raise HTTPException(status_code=409, detail="Duplicate device registration")
        
    return data

# Direct REST API call via cURL
curl -X POST https://api.botrefund.com/v1/verify \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sec_live_your_api_key" \
  -d '{
    "request_id": "req_8f31b209aef14c"
  }'