> ## Documentation Index
> Fetch the complete documentation index at: https://docs.spark360.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Idempotency

> Use event_id to deduplicate and safely handle retries.

Spark360 retries failed deliveries, so subscribers should process webhook events idempotently.

## Recommended strategy

* Use `event_id` as your idempotency key
* Store processed `event_id` values in your system
* Ignore duplicate `event_id` values on retry

## Why this matters

* Retries are expected for transient failures
* Duplicate HTTP deliveries can occur by design during retry windows
* Idempotency prevents duplicate CRM writes and repeated automations