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

# Prove possession of a webhook signing secret

> Sparkles signs this request with the same Webhook-Id.Webhook-Timestamp.rawRequestBody algorithm as event delivery. Verification requests intentionally omit sequence and Webhook-Attempt. Read data.challenge and return base64(HMAC-SHA256(base64Decode(secret without whsec_), "sparkles.webhook.verify." + challenge)) as response. Exact test vector: the example-only secret whsec_AQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQE= and the example challenge produce the example response.



## OpenAPI

````yaml /openapi.json webhook partnerEndpointVerification
openapi: 3.1.0
info:
  title: Sparkles partner API
  version: 1.0.0
  description: Create promotional credit claims and receive attributed lifecycle events.
servers:
  - url: https://sparkles.dev
security: []
paths: {}

````