How Inbound Webhooks Work in Horizon

How Inbound Webhooks Work in Horizon

What Are Inbound Webhooks?

Inbound webhooks let external systems — like your PSA, Zapier, or n8n — send data to Horizon in real time. When something happens in an external tool (a ticket is updated, a form is submitted, a rule fires), that tool sends an HTTP request to a unique Horizon URL, and Horizon can automatically trigger a workflow in response.

Key Concepts

  • Endpoint: A unique, configured receiver URL in Horizon. Each endpoint has its own token-based URL, authentication method, and expected data format. You create one endpoint per integration source.
  • Token: A 64-character secret embedded in the endpoint URL (/webhooks/v1/inbound/{token}). The token identifies which endpoint is being called — keep it private.
  • Template: A pre-configured starting point for common sources like Autotask Extension Callouts, Zapier, n8n, and Make. Templates pre-fill the auth method, data format, and known IP addresses for that source.
  • Schema: A definition of the fields Horizon expects in the webhook payload. Horizon validates every incoming payload against the schema before accepting it.
  • Webhook Log: A full audit trail of every request received by an endpoint — including the payload, source IP, processing result, and timing. Found under Admin > Webhooks > Logs.

How It Works

When an external system sends a request to a webhook endpoint URL, Horizon processes it in order:

  1. Endpoint lookup — Horizon finds the endpoint by its token and checks that it is active.
  2. IP check — If an IP allowlist is configured, Horizon verifies the request comes from a permitted address.
  3. Authentication — Horizon validates the request using the configured method (none, Basic Auth, header token, query token, or HMAC signature).
  4. Payload parsing — Horizon parses the request body using the configured format (JSON, form-urlencoded, XML-RPC, or SOAP).
  5. Schema validation — The parsed payload is validated against the endpoint's schema. Requests that don't match are rejected.
  6. Workflow trigger — If a workflow is connected to this endpoint, it fires with the validated payload data available as variables.
  7. Audit log — Every request — success or failure — is written to the webhook log with full details.

The entire pipeline runs synchronously and Horizon responds immediately with a success or error result.

Common Use Cases

  • Autotask Extension Callouts: Fire a Horizon workflow the moment a ticket is created, updated, or reaches a specific status in Autotask — without polling.
  • Zapier / n8n / Make: Trigger a Horizon workflow from any app connected to your automation platform.
  • Custom integrations: Any system that can make an HTTP POST request can send data to Horizon and kick off a workflow.

Managing Endpoints

Endpoints are managed under Admin > Webhooks > Endpoints. From there you can create new endpoints (from a template or from scratch), view and copy the webhook URL, configure security settings, connect a workflow, and review the request log for that endpoint.