TL;DR: First, three credentials, not one: register a webhook username and password in the dashboard (Finix sends them on each delivery so you can verify the caller), and separately store the webhook signing key for HMAC verification. Setting up Finix webhooks has two failure modes everyone hits. Second, the endpoint must be publicly reachable over HTTPS before you register it: Finix cannot deliver to YOUR_HOST or a private network, and a local dev URL fails silently.

```text
Finix webhooks need three credentials and a public HTTPS URL; answer the {} probe with 200
```

## Fix
1. First, three credentials, not one: register a webhook username and password in the dashboard (Finix sends them on each delivery so you can verify the caller), and separately store the webhook signing key for HMAC verification.
   Expected: this specific failure stops.

## Details
Setting up Finix webhooks has two failure modes everyone hits. One more: when you first register, Finix sends an empty/ `{}` verification delivery. Your handler must answer 200 to that probe and not try to parse an event from it.

## When to use
You hit exactly this: Finix webhooks need three credentials and a public HTTPS URL; answer the {} probe with 200 in Finix.

## When not to use
A different error, or the same symptom in a different tool. This page only covers the failure above.

## Compatibility
Finix.

## Edge cases
- Second, the endpoint must be publicly reachable over HTTPS before you register it: Finix cannot deliver to YOUR_HOST or a private network, and a local dev URL fails silently.