Kaidn docs

You send one thing that just happened: someone signed up, logged in, tried to check out, asked to withdraw money. You send whatever you already know about it, which might be an email address, an IP, a device, or all three.

Kaidn checks it against everything it knows about those details and sends back one of three answers, with an explanation attached:

You decide what to do with the answer. Kaidn never blocks anyone on your behalf and never talks to your users. It is one HTTP call that returns a judgement, and the rest is your code.

You will not be asked to move your data anywhere. There is nothing to install on your servers, no agent, no database. If you can make an HTTPS request you can use this.

1. Get a key

Create an account. You get a key immediately, no sales call and no card. The key is shown once, so put it somewhere your server can read it and never put it in a web page.

2. Send one event

event is the only field you have to send, and it is just a name you choose. Everything else is optional: send what you have, and the answer sharpens as you send more.

// npm install @kaidn/sdk
import { Kaidn } from "@kaidn/sdk";

const kaidn = new Kaidn({ apiKey: process.env.KAIDN_API_KEY });

const { verdict, reasons, reason_text } = await kaidn.score({
  event: "cashout",
  user_id: "u_8231",
  ip: req.ip,
  email: user.email,
  device_id: fingerprint,            // from @kaidn/fp in the browser
  event_country: offer.country,      // optional geo expectation
});

if (verdict === "block") return deny(reason_text);
if (verdict === "review") await queueForReview(user, reasons);

// the SDK covers every endpoint:
await kaidn.check.ip("3.5.140.1");
await kaidn.batch.score(rows);       // bulk, up to 1000 rows
await kaidn.label({ label: "chargeback", event_id });

3. Branch on the answer

Three cases, and the whole integration is usually this small to begin with.

const { verdict, reason_text } = await scoreTheSignup(req);

if (verdict === "block")  return deny();
if (verdict === "review") return holdForReview(reason_text);

return proceed();

That is the integration. Everything else in these docs makes it sharper, and none of it is required to start.

The response has a lot in it, and three fields do the work:

{
  "verdict": "block",
  "reasons": ["datacenter_ip", "disposable_email"],
  "reason_text": "The IP is a hosting provider address and the email
    uses a disposable domain. Risk score 80/100 → block.",
  "score": 80,
  ...
}

There is also a score from 0 to 100. It is bookkeeping rather than a probability, so branch on the verdict and the reasons, and treat the number as a dial you can move rather than a fact about the user.

Everything else in the response is evidence: which checks fired, what each one counted for, and the raw numbers behind them. You can ignore all of it on day one and go back to it the first time you disagree with an answer. Every field is listed in the reference.

If you only read one more page, read core concepts. It is six ideas, and it is what makes the rest of the reference obvious instead of dense.

The free tier is 10,000 scored events a month, forever, with no card. You are billed per decision, so collecting device information costs nothing extra and the free checkers and dashboard do not count against your allowance. Prices are on the pricing page, where you would expect them to be.