---
title: "Send one synchronous signed test webhook delivery"
method: POST
path: "/inboxes/{id}/webhook/test"
tags: ["inboxes"]
---

# Send one synchronous signed test webhook delivery

`POST /inboxes/{id}/webhook/test`

## Request

- Base URL: `https://dash.mailsocket.app/api/v1`
- URL: `https://dash.mailsocket.app/api/v1/inboxes/{id}/webhook/test`
- Auth: HTTP bearer

Sends exactly one synchronous, signed test event through the same
SSRF-pinned transport and signing primitives real deliveries use.
Creates NO `WebhookDelivery` row (no retry, no drain interaction), so
it never appears in delivery history. Allowed even when the webhook
is disabled (verify a receiver before enabling it). Counts toward the
monthly `webhook_attempts` usage, exactly like a real delivery attempt,
including failed/rejected attempts, not just delivered ones.

## Path parameters

- `id` string, required

## Response `200`

The test send was attempted (delivered is true whenever the transport returned any HTTP response, including non-2xx).

- object
  - `data` object, required
    - `delivered` boolean, required
    - `response_status` integer, required: The receiver's HTTP status code.
    - `signature_version` string, required
    - `event_id` string, required: Synthetic event id for this test send, prefixed `evt_test_`.

## Other responses

- `400`: The webhook URL was rejected by SSRF validation before any network call was made.
- `401`: Missing or invalid API key.
- `403`: Either account-level forbidden, or the plan does not include webhooks (`webhook_entitlement_required`).
- `404`: Either the inbox is not owned by the caller (`not_found`), or it is owned but has no webhook configured (`webhook_not_configured`).
- `429`: Per-inbox (10/hour) or per-account (30/hour) test-send rate limit exceeded.
- `502`: The transport could not reach the receiver (timeout, connection refused, TLS failure).

---

[API](https://skmtc.dev/mailsocket/apis/mailsocket-api.md) · [All operations](https://skmtc.dev/mailsocket/apis/mailsocket-api/llms.txt) · [OpenAPI document](https://skmtc.dev/mailsocket/apis/mailsocket-api/revisions/e579500dfb7e?raw)