Skip to content

Auth0 Actions and Extensibility — Custom Login Flows with Auth0 Actions

DodaTech Updated 2026-06-28 1 min read

In this tutorial, you'll learn about Auth0 Actions. We cover key concepts, practical examples, and best practices to help you understand and apply this topic effectively.

Auth0 Actions provide extensibility points in the authentication pipeline for custom logic like enriching tokens, blocking logins, or syncing user data.

// Post-Login Action: enrich token with custom claims
exports.onExecutePostLogin = async (event, api) => {
  const namespace = 'https://scan-api.example.com';

  // Enrich with user metadata
  api.accessToken.setCustomClaim(`${namespace}/scan_quota`, event.user.app_metadata?.scan_quota || 100);
  api.accessToken.setCustomClaim(`${namespace}/organization_id`, event.user.app_metadata?.org_id);

  // Conditional access based on user attributes
  if (event.user.app_metadata?.requires_mfa && event.authentication?.methods?.[0]?.type !== 'mfa') {
    api.authentication.error('requires_mfa', 'Please complete multi-factor authentication');
  }

  // Track login in external system
  const axios = require('axios');
  await axios.post(configuration.AUDIT_ENDPOINT, {
    user_id: event.user.user_id,
    login_at: new Date().toISOString(),
    ip: event.request.ip
  });
};

Actions enable event-driven extensibility without managing custom infrastructure for authentication logic.

← Previous Auth0 Custom Database — Custom Database Connections and User Migration Next → Auth0 Security Best Practices — Securing Your Auth0 Implementation

Built by the developers of DodaTech

Doda Browser, DodaZIP & Durga Antivirus Pro

Home Browse Auth0