Developer Resources

Integrations & SDKs

Add fraud detection to any stack in under 5 minutes. Works with any language that can make HTTP requests — no proprietary SDK required.

< 40ms

Average global response time

Any lang

REST API works with any HTTP client

No SDK

Plain HTTP POST, zero dependencies

API Reference

One endpoint. Full signal set.

A single POST request returns a risk score, verdict, and all detection signals. No pagination, no setup, no webhooks required to get started.

Endpoint

Method POST

URL https://api.sntlhq.com/v1/check

Auth Authorization: Bearer YOUR_API_KEY

Request { "ip": "1.2.3.4", "user_agent": "...", "headers": {} }

Response { "risk_score": 94, "verdict": "block", "signals": { "vpn": true, "proxy": false, "tor": false, "datacenter": false, "residential_proxy": true, "headless": false }, "country": "US", "latency_ms": 28 }

Code Examples

Pick your language

Copy-paste ready examples for the most common server-side languages. All examples show the full request/response flow with a block-or-pass pattern.

Node.js / JavaScript

const response = await fetch('https://api.sntlhq.com/v1/check', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    ip: req.ip,
    user_agent: req.headers['user-agent'],
    headers: req.headers
  })
});
const result = await response.json();

if (result.verdict === 'block') {
  return res.status(403).json({ error: 'Access denied' });
}

Python

import requests

response = requests.post(
    'https://api.sntlhq.com/v1/check',
    headers={
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
    },
    json={
        'ip': request.remote_addr,
        'user_agent': request.headers.get('User-Agent'),
        'headers': dict(request.headers)
    }
)
result = response.json()

if result['verdict'] == 'block':
    return jsonify({'error': 'Access denied'}), 403

PHP

$response = file_get_contents('https://api.sntlhq.com/v1/check', false, stream_context_create([
    'http' => [
        'method'  => 'POST',
        'header'  => "Authorization: Bearer YOUR_API_KEY\r\nContent-Type: application/json\r\n",
        'content' => json_encode([
            'ip'         => $_SERVER['REMOTE_ADDR'],
            'user_agent' => $_SERVER['HTTP_USER_AGENT'],
            'headers'    => getallheaders()
        ])
    ]
]));
$result = json_decode($response, true);

if ($result['verdict'] === 'block') {
    http_response_code(403);
    echo json_encode(['error' => 'Access denied']);
    exit;
}

type CheckRequest struct {
    IP        string            `json:"ip"`
    UserAgent string            `json:"user_agent"`
    Headers   map[string]string `json:"headers"`
}

func checkIP(ip, userAgent string) (*SentinelResult, error) {
    body, _ := json.Marshal(CheckRequest{IP: ip, UserAgent: userAgent})
    req, _ := http.NewRequest("POST", "https://api.sntlhq.com/v1/check", bytes.NewReader(body))
    req.Header.Set("Authorization", "Bearer YOUR_API_KEY")
    req.Header.Set("Content-Type", "application/json")

    resp, err := http.DefaultClient.Do(req)
    if err != nil { return nil, err }
    defer resp.Body.Close()

    var result SentinelResult
    json.NewDecoder(resp.Body).Decode(&result)
    return &result, nil
}

Ruby

require 'net/http'
require 'json'

uri  = URI('https://api.sntlhq.com/v1/check')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true

request = Net::HTTP::Post.new(uri.path)
request['Authorization'] = 'Bearer YOUR_API_KEY'
request['Content-Type']  = 'application/json'
request.body = {
  ip:         request.remote_ip,
  user_agent: request.user_agent,
  headers:    request.headers.to_h
}.to_json

response = http.request(request)
result   = JSON.parse(response.body)

render json: { error: 'Access denied' }, status: 403 if result['verdict'] == 'block'

Java

HttpClient client = HttpClient.newHttpClient();
String body = String.format(
    "{\"ip\":\"%s\",\"user_agent\":\"%s\"}",
    request.getRemoteAddr(),
    request.getHeader("User-Agent")
);

HttpRequest httpRequest = HttpRequest.newBuilder()
    .uri(URI.create("https://api.sntlhq.com/v1/check"))
    .header("Authorization", "Bearer YOUR_API_KEY")
    .header("Content-Type", "application/json")
    .POST(HttpRequest.BodyPublishers.ofString(body))
    .build();

HttpResponse<String> response = client.send(httpRequest,
    HttpResponse.BodyHandlers.ofString());
JSONObject result = new JSONObject(response.body());

if ("block".equals(result.getString("verdict"))) {
    response.setStatus(403);
    return Map.of("error", "Access denied");
}

Compatibility

Works with every framework

If your framework can make an outbound HTTP request, Sentinel works. No middleware, no plugins, no vendor lock-in.

Next.js

Node / React

Express.js

Node

Fastify

Node

NestJS

Node / TS

Django

Python

FastAPI

Python

Flask

Python

Laravel

PHP

Symfony

PHP

Rails

Ruby

Spring Boot

Java

Gin

Echo

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