API Reference
Billing
Domains
Emails
Hooks applications
Hooks endpoints
Hooks event types
Hooks messages
Hooks portal
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Receiving
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Webhook endpoints
Retrieve a message
GET
/v1/hooks/applications/{application}/messages/{message_id}
A message of the application, with its payload.
bearerAuthheader
AuthorizationBearer <token>A secret API key from the dashboard: coss_live_… for production environments, coss_test_… for sandbox environments.
application*stringThe application's id (happ_…) or your uid for it.
message_id*stringCoss-Version?"2026-10-10"The API version (a date) to use for this request. Defaults to your organization's version, pinned to the latest one when it first used the API and upgraded from the dashboard. The SDK always sends the version it was built for.
Value in
"2026-10-10"The message.
application/json- response
- response
- …
object*"hook_message"Value in
"hook_message"id*stringAlso the webhook-id header of every request delivering it.
application_id*stringevent_type*stringpayload*The JSON body delivered to each endpoint.
created_at*stringFormat
date-timeimport { Coss } from "coss";const coss = new Coss({ apiKey: process.env.COSS_API_KEY, baseUrl: "https://api.coss.com",});const { data, error } = await coss.hooks.messages.get("customer_8812", "hmsg_01k7c8m4q2f3e9v6t5r1n0p8yz");{ "object": "hook_message", "id": "hmsg_01k7c8m4q2f3e9v6t5r1n0p8yz", "application_id": "happ_01k7c8m4q2f3e9v6t5r1n0p8yz", "event_type": "invoice.paid", "payload": { "invoice_id": "in_1042", "amount": 4200, "currency": "usd" }, "created_at": "2026-01-15T09:30:00.000Z"}