neon-auth

# Managed Better Auth: implement login

Enabling `auth: true` is not implementing login. Follow the matching live quickstart, then verify sign-up, sign-in, sign-out, session, and a protected route.

- Overview: https://neon.com/docs/auth/overview.md
- Next.js (API methods): https://neon.com/docs/auth/quick-start/nextjs-api-only.md
- React (API methods, including React Router): https://neon.com/docs/auth/quick-start/react.md
- TanStack Router (UI components): https://neon.com/docs/auth/quick-start/tanstack-router.md

Keep Clerk, existing Better Auth, Supabase Auth, or another working provider. Do not migrate it unless the user asks. The `SKILL.md` Supabase case is that explicit login-migration request.

Framework-specific companion skills also live in [neondatabase/neon-js](https://github.com/neondatabase/neon-js) (`neon-auth-nextjs`, `neon-auth-react`, `neon-js-react`). Prefer the live Neon guides above; do not copy those SDK-local files into this repo.

## Auth emails

Managed Auth sends verification, email OTP, magic-link, and password-reset messages. Getting started uses the shared SMTP provider (`[email protected]`). Implementing login does not require Resend, SendGrid, or other application email code.

Production requires custom SMTP. Verification codes work on shared or custom SMTP. Verification links require custom SMTP. Checklist: https://neon.com/docs/auth/production-checklist.md. Branding and webhook delivery: https://neon.com/docs/auth/guides/customize-emails.md.

SMS is separate: the Phone Number plugin needs an application `send.otp` webhook.

## Packages

| Need | Package |
| --- | --- |
| Auth only | `@neondatabase/auth` |
| Already using the combined SDK | `@neondatabase/neon-js/auth` re-export |
| Pre-built UI | `@neondatabase/auth-ui` |

Keep an existing `SupabaseAuthAdapter()` caller on that API (`signInWithPassword`, `signInWithOAuth`). Do not mix those methods into default Better Auth examples. Password hashes do not migrate from Supabase; `updateUser()` cannot change email or password; email verification needs app UI. Guide: https://neon.com/docs/auth/migrate/from-supabase.md

The Managed client is Better Auth methods through Neon's wrapper. It is not interchangeable with bare `better-auth/client` while Auth is managed: the wrapper rejects extra plugins and implements Neon OAuth verifier / iframe popup / JWT extraction.

## Environment

| Variable | Purpose |
| --- | --- |
| `NEON_AUTH_BASE_URL` | Branch Managed Auth URL (includes path). Next server; injected into Functions. |
| `NEON_AUTH_COOKIE_SECRET` | Next app secret for cached session cookies. Generate with `openssl rand -base64 32` (32+ characters). Not injected by Neon. |
| `VITE_NEON_AUTH_URL` | Public Auth URL for Vite / TanStack browser code. Assign the actual branch URL; env pull does not create this alias. |
| `NEON_AUTH_JWKS_URL` | Injected Functions JWKS. Verify tokens in `neon-functions`, not here. |

`neon env pull` / `neon deploy` write Managed `NEON_AUTH_BASE_URL` and `NEON_AUTH_JWKS_URL` when Auth is declared. The cookie secret and `VITE_*` name are application config.

## Next.js

`createNeonAuth` from `@neondatabase/auth/next/server`. Optional Next peer on current `@neondatabase/auth` is `>=16.0.0`; check the installed package before changing an existing app's router file.

```typescript
import { createNeonAuth } from "@neondatabase/auth/next/server";

export const auth = createNeonAuth({
  baseUrl: process.env.NEON_AUTH_BASE_URL!,
  cookies: { secret: process.env.NEON_AUTH_COOKIE_SECRET! },
});
```

`app/api/auth/[...path]/route.ts`:

```typescript
import { auth } from "@/lib/auth/server";

export const { GET, POST, PUT, DELETE, PATCH } = auth.handler();
```

Those five methods are what the installed SDK returns. Existing apps that export only `GET`/`POST` keep serving GET/POST routes.

Browser client takes **no arguments** and talks to that same-origin proxy:

```typescript
import { createAuthClient } from "@neondatabase/auth/next";

export const authClient = createAuthClient();
```

Protect routes with `auth.middleware({ loginUrl: "/auth/sign-in" })` from `proxy.ts` on Next 16. Earlier Next apps may still use `middleware.ts`; match the installed SDK. Always set `config.matcher` to the protected pages. A matcher that covers every path redirects JavaScript and CSS for unauthenticated visitors, so the login page cannot load:

```typescript
import { auth } from "@/lib/auth/server";

export default auth.middleware({ loginUrl: "/auth/sign-in" });

export const config = {
  matcher: ["/account/:path*"],
};
```

Replace `/account/:path*` with the app's protected routes. Keep login, registration, recovery, `/api/auth`, and static assets accessible without a session.

Before reading protected data or performing a mutation, check the session inside the Route Handler or Server Action and enforce the resource's authorization rules. Verify direct unauthenticated requests are denied, independently of page redirects:

```typescript
const { data: session } = await auth.getSession();
if (!session?.user) {
  return Response.json({ error: "Unauthorized" }, { status: 401 });
}
```

Server session:

```typescript
const { data: session, error } = await auth.getSession();
const user = session?.user;
```

Do not destructure `{ user }` from the top-level result. Do not pass options into `createAuthClient()` from `/next`. Do not put `fetchOptions` on the Managed `createAuthClient` URL-style config; adapter factories accept fetch options inside `BetterAuthReactAdapter({ fetchOptions })` / `BetterAuthVanillaAdapter(...)`.

JWT: `const { data, error } = await auth.token();` then `data.token`. Do not call `getJWTToken()` on the public client.

**Phone OTP:** the browser client exposes `phoneNumber`. Existing users link a number, then sign in; there is no phone-first signup. Next.js `auth.handler()` forwards the catch-all path to Managed Auth, including phone OTP. A missing `auth.phoneNumber` server method is a missing typed helper, not a proxy rejection. SMS e2e needs a configured `send.otp` webhook and custom UI.

## Organization invitations

`organization.inviteMember()` does not send email unless `send_invitation_email` is on (default `false`) and "Verify email at signup" is enabled. Accepting an emailed invite needs `/auth/accept-invitation?invitationId=` via `AuthView` or a custom flow that signs the recipient in and calls `organization.acceptInvitation({ invitationId })`. If email delivery stays off, use an in-app invitation list. https://neon.com/docs/auth/guides/plugins/organization.md

## React / Vite

```typescript
import { createAuthClient } from "@neondatabase/auth";
import { BetterAuthReactAdapter } from "@neondatabase/auth/react/adapters";

export const authClient = createAuthClient(import.meta.env.VITE_NEON_AUTH_URL, {
  adapter: BetterAuthReactAdapter(),
});
```

Call adapter factories with `()`. Omit the adapter for vanilla Better Auth methods without `useSession`.

Public calls: `signUp.email({ email, password, name })`, `signIn.email({ email, password })`, `signIn.social({ provider, callbackURL })`, `getSession()`, `signOut()`. Result shape is `{ data, error }`; user is `data.user`. Handle `error` and thrown HTTP errors, pending UI, and authenticated vs unauthenticated display.

JWT: `authClient.token()` then `data.token`.

## UI

```typescript
import "@neondatabase/auth-ui/css";
import { NeonAuthUIProvider, AuthView } from "@neondatabase/auth-ui";
```

Choose one CSS import: `/css` or `/tailwind`, never both. Current `@neondatabase/auth-ui` uses `<AuthView path={path} />`. Check installed types before copying a `pathname` example from older docs.

UI flags (`emailOTP`, `magicLink`, social providers, organization) do not enable the Managed plugin. Configure the plugin on the branch, then the UI.

Preserve existing `@neondatabase/auth/react/ui` imports rather than forcing a drive-by migration. New snippets use `@neondatabase/auth-ui`.

## Cross-subdomain vs bearer JWT

`cookies.domain` shares session cookies across subdomains of one parent domain (see the neon-js `cross-domain-cookies` example). That is not cookie sharing across unrelated frontend and backend hosts. A Neon Function authenticates with `Authorization: Bearer`. With Managed Auth, verify against the injected JWKS. With another identity, use that identity's token contract — see `neon-functions`. https://neon.com/docs/compute/functions/authentication.md and https://neon.com/docs/auth/guides/plugins/jwt.md.

## Data API identity

Only when the app already uses PostgREST or a Supabase database client:

```typescript
import { defineConfig } from "@neon/config/v1";

export default defineConfig({ auth: true, dataApi: true });
```

Existing external IdP:

```typescript
import { defineConfig } from "@neon/config/v1";

export default defineConfig({
  dataApi: {
    authProvider: "external",
    jwksUrl: "https://your-idp/.well-known/jwks.json",
  },
});
```

Do not enable Auth merely to satisfy a `dataApi` type error in an app that never needed the Data API. External JWKS on a Claimable project is accepted only after claim. Combined SDK `createClient({ dataApi: { url, getToken } })` is a query client without `.auth`; confirm the installed `@neondatabase/neon-js` docs before introducing it.

# Self-managed Better Auth

Use this page only after `SKILL.md` routed here: a required feature is outside Managed Auth, and the installed Better Auth version documents that flow. If that check fails, keep the current identity.

## Keep existing Better Auth

If the app already runs Better Auth, keep that server, its clients, users, and sessions. It works with Lakebase Postgres, Functions, Object Storage, and the AI Gateway. Do not migrate it to Managed Auth unless the user asks.

## New self-managed server

Host it on the existing app (Vercel route handlers, or similar) when that host already serves `/api/auth`. Use a Neon Function when the auth server should sit next to Postgres, or when the Function itself must be an OAuth authorization server (MCP). Function hosting follows the `neon-functions` skill (region, claim, `neon.ts`, `neon deploy --env <file>`).

Keep Lakebase Postgres as the auth database. Use `better-auth` and `better-auth/client`. Fetch upstream docs for the **installed** version:

- https://better-auth.com/docs/installation
- https://better-auth.com/docs/concepts/client
- https://better-auth.com/docs/concepts/plugins

Do not pass `plugins` into `@neondatabase/auth`. Replacing only the client package while Managed Auth is still the backend does not add plugins.

MCP OAuth (Cursor, Claude, and similar clients self-authorizing) is `neon-functions` [references/mcp.md](https://neon.com/docs/ai/skills/neon-functions/references/mcp.md). That can sit beside existing Clerk or Managed login. Do not migrate the whole app's identity unless that was the request.

Function JWT verification, CORS, and direct browser calls: `neon-functions` and https://neon.com/docs/compute/functions/authentication.md.

There is no documented universal import from Managed `neon_auth` into a self-managed Better Auth schema. Inventory users, credentials, sessions, memberships, and application foreign keys before changing existing state. Agree a cutover plan with the owner. Do not promise drop-in session continuity.

---
name: neon-auth
description: >-
  Add authentication to a new app. Use for "add auth", "add login", Neon Auth
  (Managed Better Auth), identity routing, sign-up, sign-in, password reset,
  email OTP, magic links, organizations, phone OTP, OAuth, passkeys, MFA,
  trusted domains, invalid domain, and @neondatabase/auth. No existing identity:
  default to Managed Better Auth. Keep working Better Auth, Clerk, Supabase
  Auth, or another IdP. User asked to migrate from Supabase Auth: Managed
  Better Auth. A required plugin outside Managed support: self-managed Better
  Auth on a Neon Function or the existing app host. Also use for auth APIs in
  @neondatabase/neon-js.
metadata:
  parent: neon
  source: https://github.com/neondatabase/agent-skills/tree/main/skills/neon-auth
---

**FIRST**: Use the parent `neon` skill for a Neon overview, getting started with Neon, Neon development best practices, and more.

If the `neon` skill is not installed, fetch it from https://neon.com/docs/ai/skills/neon/SKILL.md or install it with:

```bash
neon skills -s neon -y
```

# Neon Auth

Neon Auth is Managed Better Auth: users, sessions, and auth config live in the `neon_auth` schema on the branch's Lakebase Postgres, and auth state branches with the database. The client API is the Better Auth method set (`signIn.email`, `signIn.social`, `getSession`) through `@neondatabase/auth`. That wrapper is not a drop-in for bare `better-auth/client`: it pins the plugin list and adds Neon-specific OAuth verifier, iframe popup, and JWT handling. Stay on the wrapper while Auth is managed.

This skill chooses identity, then implements Managed Better Auth. It does not replace a working auth server in order to use Postgres, Functions, Object Storage, or the AI Gateway.

## When to Use

Inspect existing identity and the required login features before provisioning. A supplied `DATABASE_URL` is not a reason to change identity. Adding a Neon Function is not a reason to change identity.

| Situation | What to do |
| --- | --- |
| No existing auth | Default to Managed Better Auth. [Managed setup](#managed-setup), then [references/managed-auth.md](references/managed-auth.md). |
| Needs a feature Managed does not offer | Self-managed Better Auth on the existing app host (Vercel or similar) or a Neon Function. Keep Lakebase Postgres. Confirm the **installed** Better Auth version documents that exact flow before recommending the move. If support stays unresolved, keep the current identity. [references/self-managed.md](references/self-managed.md). |
| Already has Better Auth | Keep it. It works with the other Neon primitives. Migrate to Managed only if the user asks. |
| User asked to migrate from Supabase Auth | Managed Better Auth. [Supabase Auth](#supabase-auth). Moving only Postgres or adding a Function keeps Supabase Auth. |
| Clerk, Auth.js, Supabase Auth, or another working IdP | Keep it unless the user asks to migrate. |

Google, GitHub, and Vercel social OAuth are offered on Managed Auth. They are not a reason to leave Managed Auth. Other OAuth providers, generic OAuth, MFA, passkeys, API keys, MCP OAuth, SSO, custom plugins, hooks, and custom JWT claims are the [plugin matrix](#plugin-support) check.

Before enabling Managed Auth, confirm the project is on AWS and does not use IP Allow or Private Networking. Leave those protections in place.

Configure supported Managed plugins through Neon (Console, API, or `neon neon-auth`), not by passing `plugins` into `@neondatabase/auth`. Enabling `auth: true` is not implementing login.

## What It Does

- **Managed identity in Postgres** — users and sessions in `neon_auth`, queryable with SQL, compatible with RLS.
- **Auth emails without an app mailer** — verification, email OTP, magic links, and password reset. Getting started uses shared SMTP (`[email protected]`). You do not add Resend or SendGrid to implement login. Production needs custom SMTP: https://neon.com/docs/auth/production-checklist.md
- **Branches with the database** — each branch has its own Auth URL and isolated auth state.
- **Better Auth client methods via the Neon SDK** — `@neondatabase/auth` (auth only) or `@neondatabase/neon-js/auth` (combined SDK). Optional UI: `@neondatabase/auth-ui`.
- **Fixed plugin set** — the Managed client does not accept a `plugins` option. See [plugin support](#plugin-support).

## Availability

Managed Better Auth is generally available. AWS regions only. It cannot be enabled on a project with IP Allow or Private Networking.

Organization is separately Partial / Beta. Hosting self-managed Better Auth in a Neon Function follows Functions availability and claim rules; use the `neon-functions` skill for that host. An unclaimed project that can enable Auth still cannot use Functions until claim.

## Managed setup

Merge Auth into the existing `neon.ts`. Do not replace other fields:

```typescript
import { defineConfig } from "@neon/config/v1";

export default defineConfig({
  auth: true,
});
```

```bash
neon deploy
neon neon-auth status
```

If Function env in that config reads `process.env`, use `neon deploy --env <file>` as the parent skill describes. The manual service command is `neon neon-auth enable`; do not run both enable and deploy as redundant required steps when `neon.ts` already declares `auth: true`.

Then implement login: [references/managed-auth.md](references/managed-auth.md).

Claimable projects: follow the parent Claimable path, then `auth: true` and `neon deploy` when login is requested and no existing provider should be preserved.

## Supabase Auth

When the user asked to migrate login from Supabase Auth, recommend Managed Better Auth and follow https://neon.com/docs/auth/migrate/from-supabase.md. Moving only Postgres or adding a Function is not that request: keep Supabase Auth.

`SupabaseAuthAdapter()` keeps method shapes such as `signInWithPassword` and `signInWithOAuth`. Those calls are not interchangeable with default Better Auth examples (`signIn.email`). Keep an existing adapter caller on that API.

Inventory the auth methods and database calls actually used:

- Password hashes cannot transfer. Users create new accounts or sign in with OAuth.
- Do not promise unchanged user IDs, sessions, or account linking. Plan application foreign keys with the owner.
- `updateUser()` cannot change email or password on Managed Auth. Email verification needs application UI (codes work on shared SMTP; links need custom SMTP).
- The migration guide lists Supabase phone/SMS/WhatsApp, SAML, and Web3 as unsupported on Managed Auth. Confirm the **installed** Better Auth version if the user still needs that exact flow; if support stays unresolved, keep Supabase Auth and stop the auth cutover. That page's "no phone auth" claim is about Supabase phone sign-in, not the constrained Managed Phone Number plugin (existing users link a number).
- `@supabase/supabase-js` used only for Auth does not justify enabling the Data API. Keep Data API only for existing PostgREST / Supabase database-client queries.

## Verification

Managed path: sign-up, sign-in, sign-out, session restoration after reload, and protected access, including error and loading states. Exercise email verification (code on shared SMTP) when it is on. Report any flow that remains unverified.

A required plugin on the self-managed path is verified in that app's Better Auth setup, not as a Managed flow.

## Plugin support

Checked 2026-09-17 against https://neon.com/docs/auth/guides/plugins.md, https://neon.com/docs/auth/roadmap.md, and the `@neondatabase/auth` client plugin list. Re-fetch those pages if this skill may be stale. An unlisted upstream plugin needs a live check; do not treat absence from this table as a dated roadmap item.

"Not exposed" means the Managed SDK/UI contract. It is not a claim that every raw server request was tested.

| Feature | Managed Auth | Boundary |
| --- | --- | --- |
| Email/password | Supported | `signUp.email`, `signIn.email` |
| Social OAuth (Google, GitHub, Vercel) | Supported | `signIn.social`. Shared Google credentials are for development; production and GitHub/Vercel need your own OAuth apps. https://neon.com/docs/auth/guides/setup-oauth.md |
| Admin | Supported | Admin session required. Plugin customization is on the roadmap. |
| Email OTP | Supported | Managed delivery. `emailOtp.sendVerificationOtp`, `signIn.emailOtp`. |
| Magic Link | Supported | Enable on the branch (off by default). `signIn.magicLink`. |
| Organization | Partial, Beta | Members, invitations, owner/admin/member. No Teams, server hooks, custom roles/permissions, or dynamic access control. Emailed invitations: [managed-auth.md](references/managed-auth.md#organization-invitations). |
| JWT | Supported | EdDSA (Ed25519), 15-minute expiry, no custom claims. Default client: `.token()` then `data.token`. `SupabaseAuthAdapter()`: `getSession()` then `data.session.access_token` (no `.token()`). |
| Open API | Supported | Server routes `/reference` and `/open-api/generate-schema`. |
| Phone Number | Supported with constraints | Browser client: existing users link a number, then sign in; no phone-first signup; own SMS webhook; custom UI. Next.js `auth.handler()` forwards the catch-all path, including phone OTP. A missing `auth.phoneNumber` server method is a missing typed helper, not a proxy rejection. https://neon.com/docs/auth/guides/plugins/phone-number.md |
| MFA / Two-Factor | Roadmap | Unavailable on Managed Auth. If required: [self-managed.md](references/self-managed.md), after confirming the installed Better Auth version. |
| Passkey, API Key, Generic OAuth, One Tap, Multi Session | Not exposed by Managed SDK/UI | If required: [self-managed.md](references/self-managed.md). Generic OAuth is not Google/GitHub/Vercel social sign-in. |
| MCP / OAuth Provider | Not Managed Auth | Third-party MCP clients self-authorizing against your server. Keep existing login. See `neon-functions` [references/mcp.md](https://neon.com/docs/ai/skills/neon-functions/references/mcp.md). |
| SSO / SAML | Not listed or exposed | If required: [self-managed.md](references/self-managed.md), after confirming the installed Better Auth version. |

The default Managed client method is `getAnonymousToken()`. That JWT is a Neon anonymous Data API token. It is not Better Auth's Anonymous-account plugin (`signIn.anonymous`). `anonymousTokenClient()` is the SDK plugin factory, not a method on the public client. Do not call it, and do not call `getAnonymousToken()` on `SupabaseAuthAdapter()`.

Trusted domains and webhooks are Neon settings, not installable Better Auth plugins.

## Trusted domains

Auth redirects only to origins on its allowlist. `invalid domain` means the app origin is missing. Include the scheme, omit a trailing slash, register production and preview origins before pointing users at them, and target the correct branch:

```bash
neon neon-auth domain add https://app.example.com
neon neon-auth domain list
neon neon-auth domain delete https://old.example.com
```

Localhost ports are pre-approved by default. An existing project can have that off: `neon neon-auth domain allow-localhost get|enable|disable`. Docs: https://neon.com/docs/auth/guides/configure-domains.md

OAuth provider redirect is `{NEON_AUTH_BASE_URL}/callback/{provider}` (the Auth URL includes its path). `callbackURL` on `signIn.social` is the later app landing origin and must be trusted.

The Managed SDK handles iframe OAuth popup and `neon_auth_session_verifier`. Keep the wrapper, callback route, and middleware. Do not reimplement that flow, and do not promise third-party cookies in every browser.

## Functions and Data API

A Function authenticates whoever already signs the user in. Do not switch identity to call a Function. Verify the token in the `neon-functions` skill and https://neon.com/docs/compute/functions/authentication.md.

Managed Auth: injected `NEON_AUTH_JWKS_URL`, issuer from `NEON_AUTH_BASE_URL`. Token: default client `.token()` then `data.token`; `SupabaseAuthAdapter()` `getSession()` then `data.session.access_token`. A valid token is not permission to read another user's rows. Sign-out ends the browser session; do not claim it immediately revokes an already-issued JWT.

Data API identity: [references/managed-auth.md](references/managed-auth.md). New apps query Postgres from Functions or existing handlers, not the Data API.