---
title: "Subscribe a callback to a data point's change events (snapshot.promoted). Requires an API key."
method: POST
path: "/v1/webhooks/subscriptions"
---

# Subscribe a callback to a data point's change events (snapshot.promoted). Requires an API key.

`POST /v1/webhooks/subscriptions`

## Request

- Base URL: `https://api.exascale.build`
- URL: `https://api.exascale.build/v1/webhooks/subscriptions`
- Auth: none declared

Body: {data_point, callback_url (https)}. Returns the subscription id and a signing secret (shown once). Deliveries are HMAC-SHA256 signed (X-Exascale-Signature) and owner-scoped. Eligible data points are served and not sub-daily cadence.

## Response `200`

subscription created

## Other responses

- `400`: invalid_request (unknown/ineligible data_point, non-https callback)
- `401`: api_key_required

---

[API](https://skmtc.dev/exascale/apis/exascale-build-rest-api.md) · [All operations](https://skmtc.dev/exascale/apis/exascale-build-rest-api/llms.txt) · [OpenAPI document](https://skmtc.dev/exascale/apis/exascale-build-rest-api/revisions/f47706905f93?raw)