create-auth

name create-auth description Scaffold and implement authentication in TypeScript/JavaScript apps using Better Auth. Detect frameworks, configure database adapters, set up route handlers, add OAuth providers, and create auth UI pages. Use when users want to add login, sign-up, or authentication to a new or existing project with Better Auth. Create Auth Skill Guide for adding authentication to TypeScript/JavaScript applications using Better Auth. For code examples and syntax, see better-auth.com/docs . Phase 1: Planning (REQUIRED before implementation) Before writing any code, gather requirements by scanning the project and asking the user structured questions. This ensures the implementation matches their needs. Step 1: Scan the project Analyze the codebase to auto-detect: Framework — Look for next.config , svelte.config , nuxt.config , astro.config , vite.config , or Express/Hono entry files. Database/ORM — Look for prisma/schema.prisma , drizzle.config.ts , package.json deps ( pg , postgres , @neondatabase/serverless , mysql2 , better-sqlite3 , mongoose , mongodb ). If drizzle.config.ts exists, read its dialect field to determine the DB type (e.g., "postgresql" → Drizzle + Postgres). Also check which Drizzle driver is installed ( drizzle-orm/node-postgres → pg , drizzle-orm/postgres-js → postgres , drizzle-orm/neon-http → Neon). Existing auth — Look for existing auth libraries ( next-auth , lucia , clerk , supabase/auth , firebase/auth ) in package.json or imports. Package manager — Check for pnpm-lock.yaml , yarn.lock , bun.lockb , or package-lock.json . Use what you find to pre-fill defaults and skip questions you can already answer. Step 2: Ask planning questions Use the AskQuestion tool to ask the user all applicable questions in a single call . Skip any question you already have a confident answer for from the scan. Group them under a title like "Auth Setup Planning". Questions to ask: Project type (skip if detected) Prompt: "What type of project is this?" Options: New project from scratch | Adding auth to existing project | Migrating from another auth library Framework (skip if detected) Prompt: "Which framework are you using?" Options: Next.js (App Router) | Next.js (Pages Router) | SvelteKit | Nuxt | Astro | Express | Hono | SolidStart | Other Database & ORM (skip if detected) Prompt: "Which database setup will you use?" Options: PostgreSQL (Prisma) | PostgreSQL (Drizzle) | PostgreSQL (pg driver) | MySQL (Prisma) | MySQL (Drizzle) | MySQL (mysql2 driver) | SQLite (Prisma) | SQLite (Drizzle) | SQLite (better-sqlite3 driver) | MongoDB (Mongoose) | MongoDB (native driver) Authentication methods (always ask, allow multiple) Prompt: "Which sign-in methods do you need?" Options: Email & password | Social OAuth (Google, GitHub, etc.) | Magic link (passwordless email) | Passkey (WebAuthn) | Phone number allow_multiple: true Social providers (only if they selected Social OAuth above — ask in a follow-up call) Prompt: "Which social providers do you need?" Options: Google | GitHub | Apple | Microsoft | Discord | Twitter/X allow_multiple: true Email verification (only if Email & password was selected above — ask in a follow-up call) Prompt: "Do you want to require email verification?" Options: Yes | No Email provider (only if email verification is Yes, or if Password reset is selected in features — ask in a follow-up call) Prompt: "How do you want to send emails?" Options: Resend | Mock it for now (console.log) Features & plugins (always ask, allow multiple) Prompt: "Which additional features do you need?" Options: Two-factor authentication (2FA) | Organizations / teams | Admin dashboard | API bearer tokens | Password reset | None of these allow_multiple: true Auth pages (always ask, allow multiple — pre-select based on earlier answers) Prompt: "Which auth pages do you need?" Options vary based on previous answers: Always available: Sign in | Sign up If Email & password selected: Forgot password | Reset password If email verification enabled: Email verification allow_multiple: true Auth UI style (always ask) Prompt: "What style do you want for the auth pages? Pick one or describe your own." Options: Minimal & clean | Centered card with background | Split layout (form + hero image) | Floating / glassmorphism | Other (I'll describe) Step 3: Summarize the plan After collecting answers, present a concise implementation plan as a markdown checklist. Example: ## Auth Implementation Plan - **Framework:** Next.js (App Router) - **Database:** PostgreSQL via Prisma - **Auth methods:** Email/password, Google OAuth, GitHub OAuth - **Plugins:** 2FA, Organizations, Email verification - **UI:** Custom forms ### Steps 1. Install `better-auth` (the CLI ships as the `auth` package and is run via `npx auth@latest`, no install needed) 2. Create `lib/auth.ts` with server config 3. Create `lib/auth-client.ts` with React client 4. Set up route handler at `app/api/auth/[...all]/route.ts` 5. Configure Prisma adapter and generate schema 6. Add Google & GitHub OAuth providers 7. Enable `twoFactor` and `organization` plugins 8. Set up email verification handler 9. Run migrations 10. Create sign-in / sign-up pages Ask the user to confirm the plan before proceeding to Phase 2. Phase 2: Implementation Only proceed here after the user confirms the plan from Phase 1. Follow the decision tree below, guided by the answers collected above. Is this a new/empty project? ├─ YES → New project setup │ 1. Install better-auth (+ scoped packages per plan) │ 2. Create auth.ts with all planned config │ 3. Create auth-client.ts with framework client │ 4. Set up route handler │ 5. Set up environment variables │ 6. Run CLI migrate/generate │ 7. Add plugins from plan │ 8. Create auth UI pages │ ├─ MIGRATING → Migration from existing auth │ 1. Audit current auth for gaps │ 2. Plan incremental migration │ 3. Install better-auth alongside existing auth │ 4. Migrate routes, then session logic, then UI │ 5. Remove old auth library │ 6. See migration guides in docs │ └─ ADDING → Add auth to existing project 1. Analyze project structure 2. Install better-auth 3. Create auth config matching plan 4. Add route handler 5. Run schema migrations 6. Integrate into existing pages 7. Add planned plugins and features At the end of implementation, guide users thoroughly on remaining next steps (e.g., setting up OAuth app credentials, deploying env vars, testing flows). Installation Core: npm install better-auth Scoped packages (as needed): Package Use case @better-auth/passkey WebAuthn/Passkey auth @better-auth/sso SAML/OIDC enterprise SSO @better-auth/stripe Stripe payments @better-auth/scim SCIM user provisioning @better-auth/expo React Native/Expo Environment Variables BETTER_AUTH_SECRET=<32+ chars, generate with: openssl rand -base64 32> BETTER_AUTH_URL=http://localhost:3000 DATABASE_URL=<your database connection string> Add OAuth secrets as needed: GITHUB_CLIENT_ID , GITHUB_CLIENT_SECRET , GOOGLE_CLIENT_ID , etc. Server Config (auth.ts) Location: lib/auth.ts or src/lib/auth.ts Minimal config needs: database - Connection or adapter emailAndPassword: { enabled: true } - For email/password auth Standard config adds: socialProviders - OAuth providers (google, github, etc.) emailVerification.sendVerificationEmail - Email verification handler emailAndPassword.sendResetPassword - Password reset handler Full config adds: plugins - Array of feature plugins session - Expiry, cookie cache settings account.accountLinking - Multi-provider linking rateLimit - Rate limiting config Export types: export type Session = typeof auth.$Infer.Session Client Config (auth-client.ts) Import by framework: Framework Import React/Next.js better-auth/react Vue better-auth/vue Svelte better-auth/svelte Solid better-auth/solid Vanilla JS better-auth/client Client plugins go in createAuthClient({ plugins: [...] }) . Common exports: signIn , signUp , signOut , useSession , getSession Route Handler Setup Framework File Handler Next.js App Router app/api/auth/[...all]/route.ts toNextJsHandler(auth) → export { GET, POST } Next.js Pages pages/api/auth/[...all].ts toNextJsHandler(auth) → default export Express Any file app.all("/api/auth/*", toNodeHandler(auth)) SvelteKit src/hooks.server.ts svelteKitHandler(auth) SolidStart Route file solidStartHandler(auth) Hono Route file auth.handler(c.req.raw) Next.js Server Components: Add nextCookies() plugin to auth config. Database Migrations Adapter Command Built-in Kysely npx auth@latest migrate (applies directly) Prisma npx auth@latest generate --output prisma/schema.prisma then npx prisma migrate dev Drizzle (dev) npx auth@latest generate --output src/db/auth-schema.ts then npx drizzle-kit push Drizzle (prod) npx auth@latest generate --output src/db/auth-schema.ts then npx drizzle-kit generate then npx drizzle-kit migrate Note: drizzle-kit push skips migration files and is only safe for development. Use drizzle-kit generate + drizzle-kit migrate in production. Re-run after adding plugins. Database Adapters Database Setup SQLite Pass better-sqlite3 or bun:sqlite instance directly PostgreSQL Pass pg.Pool instance directly MySQL Pass mysql2 pool directly Prisma prismaAdapter(prisma, { provider: "postgresql" }) from better-auth/adapters/prisma Drizzle (pg) drizzleAdapter(db, { provider: "pg" }) from better-auth/adapters/drizzle Drizzle (mysql) drizzleAdapter(db, { provider: "mysql" }) from better-auth/adapters/drizzle Drizzle (sqlite) drizzleAdapter(db, { provider: "sqlite" }) from better-auth/adapters/drizzle MongoDB mongodbAdapter(db) from better-auth/adapters/mongodb Drizzle + PostgreSQL Setup Before using drizzleAdapter , initialize the db instance: // Option 1: node-postgres (pg) import { drizzle } from "drizzle-orm/node-postgres" import { Pool } from "pg" import * as schema from "./auth-schema" const pool = new Pool ({ connectionString : process. env . DATABASE_URL }) export const db = drizzle (pool, { schema }) // Option 2: postgres.js import { drizzle } from "drizzle-orm/postgres-js" import postgres from "postgres" import * as schema from "./auth-schema" const client = postgres (process. env . DATABASE_URL !) export const db = drizzle (client, { schema }) // Option 3: Neon serverless import { drizzle } from "drizzle-orm/neon-http" import { neon } from "@neondatabase/serverless" import * as schema from "./auth-schema" const sql = neon (process. env . DATABASE_URL !) export const db = drizzle (sql, { schema }) Then pass to Better Auth: import { betterAuth } from "better-auth" import { drizzleAdapter } from "better-auth/adapters/drizzle" import { db } from "./db" export const auth = betterAuth ({ database : drizzleAdapter (db, { provider : "pg" }), // ... }) Drizzle Config ( drizzle.config.ts ) Required for drizzle-kit commands to find your schema: import { defineConfig } from "drizzle-kit" export default defineConfig ({ schema : "./src/db/auth-schema.ts" , out : "./drizzle" , dialect : "postgresql" , dbCredentials : { url : process. env . DATABASE_URL !, }, }) Common Plugins | Plugin | Server Import | Client Import | Purpose |