POST /v1/watchlist/webhook

Set, test or remove the watchlist webhook

Get pushes instead of polling: set an https URL on your key and Poseidon POSTs the new changes of your watched brands (new ads, stopped ads, more versions, reused media, reach growth) about every hour, signed with HMAC-SHA256 (header Poseidon-Signature: t=…,v1=…; the secret is returned once when the URL is set), retried with backoff for about 15 hours. Each push costs what watchlist_changes costs (5 credits per brand with something new). Without arguments: shows the webhook and its recent deliveries. Free to set.

Verify a push: compute HMAC-SHA256(secret, '<t>.<raw body>') and compare it with v1 in Poseidon-Signature; reject t older than 5 minutes. Retries: 1 min, 5 min, 30 min, 2 h, 12 h. Cost: free to set; each push 5 credits per brand with something new.

Cost: Free.

Parameters

No parameters.

Errors

`400`	A parameter is refused (the answer lists the accepted values). Not billed.
`401`	Missing, unknown or revoked API key.
`429`	Too many requests for this key. Wait Retry-After seconds. Not billed.
`503`	Server busy or a query took too long. Retry. Not billed.