AbuseGraph + NextAuth

Quick path

1. Copy a test key from the console; no package installation is required for the browser or HTTPS API path.
2. Collect browser signals on auth forms → toCheckBody → send to your server route.
3. Use callbacks.signIn to gate login; check signup in your account-creation handler.

Keys

Free includes 1,000 live API checks / month after DNS verify. Test keys never bill.

Env

ABUSEGRAPH_SITE=yourdomain.com
ABUSEGRAPH_CHECK_URL=https://abusegraph.com/api/v1/check
ABUSEGRAPH_SECRET_KEY=sk_test_…
ABUSEGRAPH_SECRET_KEY_TEST=sk_test_…
NEXT_PUBLIC_ABUSEGRAPH_PUBLISHABLE_KEY=pk_test_…

Use sk_live_… / pk_live_… in production after DNS verify.

Server check

Call the HTTPS API from your server. Keep ABUSEGRAPH_SECRET_KEY in server-only environment configuration. Events: signup | login | password_reset | email_change; sessionId is optional.

const API = "https://abusegraph.com/api/v1/check";

export async function scoreAuth(input: Record<string, unknown>) {
  const site = process.env.ABUSEGRAPH_SITE!;
  const response = await fetch(API, {
    method: "POST",
    headers: {
      "content-type": "application/json",
      "x-api-key": process.env.ABUSEGRAPH_SECRET_KEY!,
      "x-abusegraph-site": site,
    },
    body: JSON.stringify({
      ...input,
      event: typeof input.event === "string" ? input.event : "signup",
      site,
    }),
  });
  if (!response.ok) throw new Error(`AbuseGraph check failed: ${response.status}`);
  return response.json();
}

Run this before creating an account or issuing a session. Handle block and challenge according to your policy; 402 means the live monthly allowance is exhausted.

Browser signals (recommended)

Load the browser SDK from the AbuseGraph CDN before your signup/login code. The publishable key is safe to expose; send the resulting body to your own backend, which makes the authoritative check with its server-held secret key.

<script src="https://abusegraph.com/sdk/abusegraph.min.js"></script>
<script>
  const sdk = AbuseGraph.init({ publicKey: "pk_test_…" });

  async function collectForAuth(email, event = "signup") {
    const collected = await sdk.collect();
    const evaluated = await sdk.evaluate(collected, { email });
    return sdk.toCheckBody(collected, {
      email,
      event,
      verdictToken: evaluated.verdictToken?.token,
    });
  }
</script>

POST the returned JSON to your own endpoint. Never treat the browser result as the authoritative decision or put an sk_ key in browser code.

Auth.js / NextAuth callbacks

Use callbacks.signIn to block before Auth.js issues a session. Auth.js events run after the auth action and are suitable for monitoring, not enforcement. Check signup in your account-creation handler before creating the user.

// auth.ts

export const authConfig = {
  callbacks: {
    async signIn({ user }) {
      if (!user.email) return false
      const result = await scoreAuth({
        email: user.email,
        userId: user.id,
        event: "login",
      })
      return result.verdict !== "block"
    },
  },
}

Lifecycle events

• login — callbacks.signIn with event: "login"; use events.signIn only for monitoring.
• password_reset — call check in your reset route with event: "password_reset".
• email_change — call before applying the email update with event: "email_change".

Platform

Lists, rules, and linked accounts apply on every check — configure in the console. Optional session: POST /api/v1/session. Native apps: iOS, Android, React Native.

Verify

Sign up once with sk_test_…, then open Activity. Blocked users should not retain a session.