Webhook interceptors

An interceptor is the mirror image of a test inbox: instead of catching email, it catches HTTP requests. Point a system under test at an interceptor URL, then read back exactly what it sent.

Creating one

Tools → Webhook Interceptor → New, or over the API:

POST /v1/webhooks

Each interceptor has a capture URL of the form https://webhooks.mailcatchr.com/<key>. The key in the path is the only credential, so treat the URL as a secret.

What it does with a request

• Records the method, path, query, headers, body, source address and time.
• Answers with the response you configured: status, content type and body. The default is 200 with an empty body.
• Optionally forwards the request to a URL of yours, and records the outcome. Use it to keep a searchable history of production webhooks while still delivering them.

Reading requests

GET /v1/webhooks/{webhookId}/requests?page=1&pageSize=50
GET /v1/webhooks/requests/{requestId}

The list returns summaries newest first. The detail includes headers and, when the body is text, the body itself. A captured request can be replayed to the forward URL, and a webhook’s history can be cleared.

Retention and limits

Captured requests are kept for the interceptor’s retention window, then deleted.

Plan	Interceptors
Free	1
Business	50

A workspace API key sees every interceptor in its workspace.