From features
Handles Clerk webhooks for real-time events like user, session, and organization changes. Includes verification, routing, and integration patterns.
How this skill is triggered — by the user, by Claude, or both
Slash command
/features:clerk-webhooksThis skill is limited to the following tools:
The summary Claude sees in its skill listing — used to decide when to auto-load this skill
Output complete, working webhook handlers with `verifyWebhook(req)` verification in every handler.
Output complete, working webhook handlers with verifyWebhook(req) verification in every handler.
Webhooks are asynchronous and eventually consistent. Delivery is fast but not guaranteed to be immediate, and may occasionally fail (Svix retries on a fixed schedule). Use them for:
Do NOT rely on webhook delivery as part of a synchronous flow such as onboarding ("user signs up, then we read X from our DB"). For data the user just created, read it from the Clerk session token or call the Backend API directly. Webhooks fill the gap when you need data about other users or events the session token doesn't carry.
Use verifyWebhook(req) from the framework-specific package (@clerk/nextjs/webhooks, @clerk/express/webhooks, etc.). It reads CLERK_WEBHOOK_SIGNING_SECRET automatically and throws on bad signatures. Skipping verification, even for notification-only handlers, exposes the endpoint to spoofed events.
Webhook routes must be excluded from Clerk middleware protection. Without this, Clerk returns 401.
// proxy.ts (Next.js <=15: middleware.ts)
import { clerkMiddleware, createRouteMatcher } from '@clerk/nextjs/server'
const isPublicRoute = createRouteMatcher(['/api/webhooks(.*)'])
export default clerkMiddleware(async (auth, req) => {
if (!isPublicRoute(req)) await auth.protect()
})
// app/api/webhooks/route.ts
import { verifyWebhook } from '@clerk/nextjs/webhooks'
import { NextRequest } from 'next/server'
import { db } from '@/lib/db'
export async function POST(req: NextRequest) {
// ALWAYS verify - never skip, even for notification-only handlers
let evt
try {
evt = await verifyWebhook(req) // uses CLERK_WEBHOOK_SIGNING_SECRET automatically
} catch (err) {
console.error('Webhook verification failed:', err)
return new Response('Verification failed', { status: 400 })
}
if (evt.type === 'user.created') {
const { id, email_addresses, first_name, last_name } = evt.data
const email = email_addresses[0]?.email_address
const name = `${first_name ?? ''} ${last_name ?? ''}`.trim()
await db.users.create({ data: { clerkId: id, email, name } })
}
if (evt.type === 'user.updated') {
const { id, email_addresses, first_name, last_name } = evt.data
const email = email_addresses[0]?.email_address
await db.users.update({ where: { clerkId: id }, data: { email, first_name, last_name } })
}
if (evt.type === 'user.deleted') {
const { id } = evt.data
await db.users.delete({ where: { clerkId: id } })
}
if (evt.type === 'organizationMembership.created') {
const { organization, public_user_data, role } = evt.data
const orgId = organization.id
const userId = public_user_data.user_id
await db.teamMembers.create({ data: { orgId, userId, role } })
}
if (evt.type === 'organizationMembership.deleted') {
const { organization, public_user_data } = evt.data
const orgId = organization.id
const userId = public_user_data.user_id
await db.teamMembers.delete({ where: { orgId_userId: { orgId, userId } } })
}
return new Response('OK', { status: 200 })
}
Notification-only handlers still verify the signature. Same pattern as the database-sync handler:
// app/api/webhooks/route.ts
import { verifyWebhook } from '@clerk/nextjs/webhooks'
import { NextRequest } from 'next/server'
import { Resend } from 'resend'
const resend = new Resend(process.env.RESEND_API_KEY)
export async function POST(req: NextRequest) {
// Step 1: ALWAYS verify the webhook signature - NEVER skip this
let evt
try {
evt = await verifyWebhook(req) // uses CLERK_WEBHOOK_SIGNING_SECRET env var
} catch (err) {
console.error('Webhook verification failed:', err)
return new Response('Verification failed', { status: 400 })
}
// Step 2: Listen for user.created event
if (evt.type === 'user.created') {
// Step 3: Extract user email and name from webhook payload
const { id, email_addresses, first_name, last_name } = evt.data
const email = email_addresses[0]?.email_address
const name = `${first_name ?? ''} ${last_name ?? ''}`.trim()
// Step 4: Call Resend API to send welcome email
await resend.emails.send({
from: '[email protected]',
to: email,
subject: 'Welcome!',
html: `<p>Hi ${name}, welcome to our app!</p>`,
})
// Step 5: Post notification to Slack channel
await fetch(process.env.SLACK_WEBHOOK_URL!, {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify({
text: `New user signed up: ${name} (${email})`,
}),
})
}
// Always return 200 to acknowledge receipt
return new Response('OK', { status: 200 })
}
Also include proxy.ts (Next.js <=15: middleware.ts) to make the route public:
// proxy.ts (Next.js <=15: middleware.ts)
import { clerkMiddleware, createRouteMatcher } from '@clerk/nextjs/server'
const isPublicRoute = createRouteMatcher(['/api/webhooks(.*)'])
export default clerkMiddleware(async (auth, req) => {
if (!isPublicRoute(req)) await auth.protect()
})
// app/api/webhooks/route.ts
import { verifyWebhook } from '@clerk/nextjs/webhooks'
import { NextRequest } from 'next/server'
import { db } from '@/lib/db' // your database client
export async function POST(req: NextRequest) {
// ALWAYS verify signature - never skip, even for simple handlers
let evt
try {
evt = await verifyWebhook(req) // uses CLERK_WEBHOOK_SIGNING_SECRET env var
} catch (err) {
console.error('Webhook verification failed:', err)
return new Response('Verification failed', { status: 400 })
}
if (evt.type === 'organization.created') {
const { id, name } = evt.data
await db.workspaces.create({
data: { orgId: id, name, createdAt: new Date() },
})
}
if (evt.type === 'organizationMembership.created') {
// Extract organization ID, user ID, and role from payload
const { organization, public_user_data, role } = evt.data
const orgId = organization.id
const userId = public_user_data.user_id
// Add to team_members table
await db.team_members.create({
data: { orgId, userId, role },
})
// Create workspace record for new member
await db.workspaces.create({
data: { orgId, userId, createdAt: new Date() },
})
}
if (evt.type === 'organizationMembership.deleted') {
// Extract organization ID and user ID from payload
const { organization, public_user_data } = evt.data
const orgId = organization.id
const userId = public_user_data.user_id
// Remove from team_members table
await db.team_members.delete({
where: { orgId, userId },
})
// Remove workspace record
await db.workspaces.deleteMany({
where: { orgId, userId },
})
}
// Return 200 status on success
return new Response('OK', { status: 200 })
}
For Express, Astro, Fastify, Nuxt, React Router, and TanStack Start, use the framework-specific verifyWebhook adapter. Each Clerk SDK package ships its own (@clerk/express/webhooks, @clerk/astro/webhooks, @clerk/fastify/webhooks, etc.).
See references/frameworks.md for full handler examples per framework.
evt.dataverifyWebhook returns WebhookEvent, a discriminated union of all event types. Narrow with evt.type to get type-safe access to evt.data:
const evt = await verifyWebhook(req)
if (evt.type === 'user.created') {
// evt.data is now UserJSON, autocompletes id, email_addresses, etc.
console.log(evt.data.id)
}
For manual typing of nested payloads, import the JSON types from your framework's webhook subpath: DeletedObjectJSON, EmailJSON, OrganizationInvitationJSON, OrganizationJSON, OrganizationMembershipJSON, SessionJSON, SMSMessageJSON, UserJSON.
user.created, user.updated, user.deleted)const {
id, // Clerk user ID
email_addresses, // array; [0].email_address is primary email
first_name,
last_name,
image_url,
public_metadata,
} = evt.data
organization.created, organization.updated, organization.deleted)const {
id, // org ID
name, // org name
slug,
} = evt.data
organizationMembership.created, organizationMembership.updated, organizationMembership.deleted)const {
organization, // { id, name, ... }
public_user_data, // { user_id, first_name, last_name, ... }
role, // e.g. 'org:admin', 'org:member'
} = evt.data
// Access: organization.id, public_user_data.user_id, role
User: user.created user.updated user.deleted
Session: session.created session.ended session.removed session.revoked
Organization: organization.created organization.updated organization.deleted
Organization Membership: organizationMembership.created organizationMembership.updated organizationMembership.deleted
Organization Domain: organizationDomain.created organizationDomain.updated organizationDomain.deleted
Organization Invitation: organizationInvitation.accepted organizationInvitation.created organizationInvitation.revoked
Communication: email.created sms.created
Waitlist: waitlistEntry.created waitlistEntry.updated
Permission: permission.created permission.updated permission.deleted
Role: role.created role.updated role.deleted
Subscription: subscription.created subscription.updated subscription.active subscription.pastDue
Subscription Item: subscriptionItem.created subscriptionItem.active subscriptionItem.updated subscriptionItem.canceled subscriptionItem.upcoming subscriptionItem.ended subscriptionItem.abandoned subscriptionItem.incomplete subscriptionItem.pastDue subscriptionItem.freeTrialEnding
Payment: paymentAttempt.created paymentAttempt.updated
Retries: Svix retries failed webhooks on a set schedule (see Svix Retry Schedule). Return 2xx to succeed, 4xx/5xx to retry. Use the svix-id header as an idempotency key to deduplicate retried events.
Replay: Failed webhooks can be replayed from Dashboard.
| Symptom | Cause | Fix |
|---|---|---|
| Verification fails (Next.js) | Wrong import or usage | Use @clerk/nextjs/webhooks, pass req directly |
| Verification fails (Express) | Using express.json() | Use express.raw({ type: 'application/json' }) for webhook route |
| Route not found (404) | Wrong path | Use /api/webhooks or preserve existing path |
| Not authorized (401) | Route is protected by middleware | Make route public in clerkMiddleware() |
| No data in DB | Async job pending | Wait/check logs |
| Duplicate entries | Only handling user.created | Also handle user.updated |
| Timeouts | Handler too slow | Queue async work, return 200 first |
Local: Tunnel localhost:3000 to the internet so Clerk can reach the endpoint. Common options: ngrok, localtunnel, Cloudflare Tunnel. Add the public URL to the Dashboard endpoint.
Production: Update webhook endpoint URL to production domain. Copy CLERK_WEBHOOK_SIGNING_SECRET to production env vars.
| Reference | Description |
|---|---|
references/frameworks.md | Webhook handler examples for Express, Astro, Fastify, Nuxt, React Router, TanStack Start |
clerk-setup - Initial Clerk installclerk-orgs - Org membership eventsclerk-billing - Subscription, subscription item, and payment attempt eventsclerk-backend-api - Sync via direct API callsnpx claudepluginhub clerk/skills --plugin mobileSets up Clerk webhook endpoints in Next.js to verify signatures and handle auth events for user sync using @clerk/backend or Svix.
Provides expert patterns for Clerk authentication in Next.js, including middleware, route protection, organizations, webhooks, and user sync.
Implements Klaviyo webhooks with HMAC-SHA256 signature verification, event handling, idempotency, and API subscriptions for profile/list/segment/campaign/flow events.