Summary
Register a message.received webhook for this inbox. Body url is a public http or https address. Localhost, a private IP, and a name that resolves to one are rejected. The default client_id is notify:{inbox id}, so a second call updates the URL. The signing secret is returned on the first create and redacted after that. Deliveries use x-cooper-signature, x-cooper-signature-v2, x-cooper-timestamp, and x-cooper-delivery. A redirect is not followed. A trigger URL from Zapier, Make, or n8n can be the url. MCP: notify_url on cooper_create_inbox. The catalog has 67 tools.
Request
{
"url": "https://example.com/hooks/cooper"
}Response
The OpenAPI document does not declare a JSON response schema for this call. The summary is the contract.Errors
The summary and the OpenAPI operation do not name an error code.
Idempotency
client_id makes this write idempotent. Sending the same client_id again returns the original object instead of creating a duplicate.