> ## Documentation Index
> Fetch the complete documentation index at: https://developer.hellgate.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Event notification

> Sent by Specter to your registered webhook URL when a subscribed decision event occurs. Respond with a 2xx status to acknowledge receipt; non-2xx responses are retried.



## OpenAPI

````yaml /products/specter/openapi.yaml webhook event_notification
openapi: 3.1.0
info:
  contact:
    email: hello@starfish.team
    name: Starfish GmbH & Co. KG
    url: https://hellgate.io/cpa/specter
  description: Composable decision engine and fraud prevention service.
  license:
    name: Hellgate API Terms
    url: https://hellgate.io/terms-and-conditions
  title: Specter API
  version: '1.0'
servers:
  - description: Managed instance of Specter
    url: https://{instance}.{env}.on-hellgate.cloud
    variables:
      instance:
        default: my-instance
        description: Your unique instance slug, provided during onboarding.
      env:
        default: eu1
        description: Deployment environment (currently eu1).
security: []
tags:
  - description: Evaluate transactions and retrieve decision results.
    name: Decisions
  - description: Close decisions that were flagged for manual review.
    name: Resolutions
  - description: Report payment lifecycle events for a prior decision.
    name: Lifecycle Events
  - description: Manage rulesets and their activation lifecycle.
    name: Rulesets
  - description: Configure interceptors and intercept live payment requests.
    name: Interceptors
  - description: Subscribe to decision and event notifications.
    name: Webhooks
  - description: Manage blocked field values.
    name: Blacklist
paths: {}

````