Webhook debugger for coding agents
Debug webhooks by asking your coding agent
Connect Claude Code, Cursor, or Codex over MCP or the CLI. Your agent gets 46 tools to inspect payloads, replay requests, and verify the fix while you watch.
No credit card, see pricing. The live endpoint is already listening.
The test event fires a Stripe-shaped payload at your endpoint. No terminal, no signup.
Trusted by engineers at
Shopify
Docker
Boeing
Cisco
IBM
T-Mobile
Okta
Wiz
Razorpay
HackerOne
Five tools, two operators
Five webhook tools that answer to you, and to your agent.
Hooklistener is a webhook debugger with an MCP server. You work in the dashboard; your coding agent works over MCP or the CLI. Same endpoints, same captured requests, same replay — nothing here is dashboard-only.
Show me the last Stripe webhook payload
46 MCP tools available
Endpoints, requests, monitors, email, automations, diagnosis
MCP server. Hand webhook debugging to your coding agent
Connect Claude Code, Cursor, or Codex to Hooklistener over MCP. Your agent creates the endpoint, waits for the webhook to land, reads the payload, and tells you what broke — without you opening a browser tab.
Drive it fromClaude Code · Cursor · Codex · Any MCP client
Learn about the MCP server- 46 tools across 9 categories, endpoints through AI diagnosis
- Works with Claude Code, Cursor, Codex, any MCP client
- Streamable HTTP transport (JSON-RPC 2.0), OAuth 2.1 + PKCE
- One command to install, no config file to hand-edit
https://hooks.hooklistener.com/w/my-endpoint-x7kqDebug Endpoints. Capture every request, replay it anywhere
Unique HTTPS endpoints that record the whole request. Inspect it in the dashboard, or have your agent pull the same payload over MCP and replay it against staging or localhost.
Drive it fromDashboard · MCP · CLI
Learn about Debug Endpoints- Full HTTP capture: method, headers, body, query, cookies, IP
- Replay to production, staging, or localhost via CLI tunnel
- Custom response codes (100-599) to exercise retry logic
- Read-only share links — send the request, not account access
- 1 to 60 days of request history, depending on plan
Stripe Payments Monitor
stripe-webhook-prod
Timeout
30 min
Last request
2m ago
Alert channels
Monitors. Know when a webhook stops arriving
Monitors watch each endpoint for silence and page you before your users notice. Your agent can read the same status mid-task and tell you which integration went quiet.
Drive it fromDashboard · MCP
Learn about Monitors- Timeout thresholds from 1 minute to 24 hours
- Email and Slack alerts, cooldowns so one outage sends one alert
- Last-request tracking with retained alert history
- Status readable over MCP while your agent works
notifications-a8x2@hookinbox.comYour order has been confirmed and is being processed...
Forwarding to:
https://api.myapp.com/webhooks/emailhttps://automation.zapier.com/hooks/...Email Inboxes. Turn any email into a webhook
Create an address and every message that arrives is forwarded as an HTTP request. Useful for parsing transactional mail, and for agents that need to test a signup flow end to end without a mailbox.
Drive it fromDashboard · MCP
Learn about Email Inboxes- Unique @hookinbox.com addresses
- Full capture: text, HTML, headers, attachments
- Fan out to several forwarding endpoints at once
- Automatic retries with delivery history
Forwarding to localhost:3000
47 requests received this session
CLI. Tunnel live webhooks to localhost
One command forwards real traffic to the port you already have running. No ngrok, no redeploy, no inbound firewall rule — and because it is a shell command, your agent can run it too.
Drive it fromTerminal · Agent shell · CI
Learn about the CLI tunnel- Device-code login, no API key to paste
- WebSocket tunnel that works behind firewalls and NAT
- Replay any captured request straight at localhost
- Scriptable from CI or from an agent's shell
MCP server
Your agent debugs the webhook over MCP. You read the summary.
Connect once and Claude Code, Cursor, or Codex get 46 tools for endpoints, events, replays, monitors, and email inboxes, then use them without leaving the editor.
- You:
Stripe checkout webhooks are failing in staging. Figure out why.
- Agent calls the Hooklistener MCP tool MCPlist_requests(endpoint: "stripe-staging", status: "5xx", since: "2h")0.4s14 failures · all checkout.session.completed · first at 09:12
- Agent calls the Hooklistener MCP tool MCPget_request(id: "evt_9f2ac41")0.3s500 from your app — signature rejected"type": "checkout.session.completed""stripe-signature": "t=1754382712,v1=8b3c…""response_status": 500"response_body": "Webhook signature verification failed"
- Agent:
The signature header is valid on all 14 — staging is the one rejecting them. Your signing secret was rotated at 09:07, five minutes before the first 500. STRIPE_WEBHOOK_SECRET still holds the old value. Updated it and redeployed.
- Agent calls the Hooklistener MCP tool MCPforward_request(endpoint: "stripe-staging", ids: "14 failed")2.1s14 replayed · 14 × 200 · avg 138 ms
- Agent calls the Hooklistener MCP tool MCPcreate_monitor(endpoint: "stripe-staging", silent_for: "30m", notify: "#payments")0.2smonitor active
- Agent concludes:
Root cause: a rotated signing secret staging never picked up. All 14 checkout events replayed clean, and the next silent half hour pings #payments before a customer does.
One command, no config. Prefer a terminal? The same tools ship in the CLI.
Use cases
Four things developers use a webhook debugger for.
Each one is a few clicks or a single command away. Works with anything that can send an HTTP request: Stripe, GitHub, Shopify, Twilio, your own services.
Debug a provider integration
Point Stripe, Shopify, or GitHub at a Debug Endpoint and watch payloads arrive live. Inspect headers, verify signatures, and replay any request against staging or production.Replay to any environmentKnow when webhooks stop arriving
Put a Monitor on a critical endpoint and get told the moment traffic goes quiet — by email or Slack, not by a support ticket three days later.Email and Slack alertsTurn email into webhooks
Some systems only send email. Give them an Email Inbox address, and order confirmations, reports, and alerts get parsed into JSON and POSTed to the endpoint of your choice.Parsed into JSON, forwarded onReceive webhooks on localhost
One CLI command forwards live traffic to your dev server. Your coding agent can run that command too, then read the captured requests back through the MCP server.No ngrok account required
CLI tunnel
Tunnel webhooks to localhost with one command.
Get a public HTTPS URL that forwards straight to your dev server. Every request through the tunnel is captured, inspectable, and replayable — and your coding agent can open one itself, since the tunnel is just a CLI command.
Custom responses
Make your test endpoint fail on purpose.
Providers time out, rate-limit you, and return shapes their docs never mention. Set the status, headers, body, and latency your endpoint replies with, and reproduce that behavior whenever you need it instead of waiting for it in production.
Set the response
Choose the HTTP status, add response headers, and write the JSON or plain-text body your endpoint returns to the caller.
Add latency and errors
Hold responses for a fixed delay or return intermittent 5xx errors, then let your agent run the integration against it and confirm the retry and backoff paths actually work.
Reuse it everywhere
The same endpoint works in local dev, CI, and staging. Change the response rules per environment without touching application code.
- status
- 503 Service Unavailable
- delay
- 2500 ms
- header
- Retry-After: 30
- body
- { "error": "try again later" }
# every caller sees this reply until you switch the rule off
Questions
Frequently asked questions about Hooklistener
Everything else lives in the documentation (opens in a new tab).
What is Hooklistener?
Can I use Hooklistener for free?
Can my AI coding agent use Hooklistener?
claude mcp add --transport http hooklistener https://app.hooklistener.com/api/mcpOAuth signs you in through the browser, so there is no API key to paste. Your agent then has 46 tools covering Debug Endpoints, captured requests, automations, schedules, secrets, Email Inboxes, and Monitors. In practice that means it can create an endpoint, block until the next webhook lands, read the payload, and explain why your handler returned a 500, without you leaving the terminal. Setup guide for Claude Code, Cursor, and Codex.What is the Hooklistener MCP server?
https://app.hooklistener.com/api/mcp that publishes 46 webhook tools across 9 categories: Debug Endpoints, requests, automations, schedules, secrets, a key-value datastore, Monitors, Email Inboxes, and AI request analysis. It runs over Streamable HTTP (JSON-RPC 2.0), authenticates with OAuth 2.0 (legacy hklst_ API keys still work), and is available on every plan including Free. There is nothing to install or self-host. See the full tool list or read what an MCP server is.Do I still get a dashboard if my agent does the debugging?
What are Debug Endpoints?
How do Monitors work?
How does the CLI work?
What is a webhook?
What are Email Inboxes?
notifications@hookinbox.com) that automatically convert incoming emails into HTTP webhooks. When an email arrives, Hooklistener parses the content (from, to, subject, body, attachments) and forwards it to your configured HTTP endpoints. Your agent can also create an inbox and wait for a message to arrive, which makes signup and password-reset flows testable end to end. Email to webhook.Why do teams choose Hooklistener over webhook.site or Hookdeck?
- An MCP server with 46 tools, so Claude Code, Cursor, and Codex can debug webhooks directly, not a UI you have to copy payloads out of.
- Debug Endpoints with up to 60-day retention, request replay, and team sharing, not just temporary request bins.
- Monitors that alert you by email and Slack when integrations break, before customers notice.
- Email Inboxes that convert any email into webhooks for workflow automation.
- CLI tunneling for local development without complex ngrok configurations.
Can I test webhooks locally?
- Install the CLI:
npm install -g hooklistener - Authenticate:
hooklistener authand follow the device code flow. - Start tunneling:
hooklistener tunnel your-endpoint-slug --port 3000 - Receive live webhooks on localhost:3000 with full request details.
How does Hooklistener handle security?
How long are webhook payloads retained?
One command to connect
Give your coding agent a webhook debugger.
Connect Claude Code, Cursor, or Codex to the MCP server and your agent gets 46 tools for endpoints, requests, automations, schedules, and email. You get the same data live in the dashboard.
Free plan includes MCP access. No credit card required.