# Webhook subscription test

Sent only when you request a test delivery for a webhook subscription.

Product: Payment API
Event reference version: 0.1.0 (current)
OpenAPI contract: https://docs.axiym.io/openapi/payment-api/events/0.1.0.yaml
Canonical page: https://docs.axiym.io/payment-api/events/0.1.0/webhook-subscription/onSubscriptionTest

[Compact reference](/payment-api/events/0.1.0/webhook-subscription/onSubscriptionTest.md)

## POST /webhooks/subscription.test

## Authentication

```json
{
  "security": [],
  "securitySchemes": {}
}
```

## Parameters

### header: X-Signature

```json
{
  "name": "X-Signature",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string"
  },
  "description": "Ed25519 signature of the raw request body."
}
```

### header: X-Key-Id

```json
{
  "name": "X-Key-Id",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string",
    "format": "uuid"
  },
  "description": "Identifier of the public key used to verify the delivery signature."
}
```

### header: X-Algorithm

```json
{
  "name": "X-Algorithm",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string",
    "const": "Ed25519"
  },
  "description": "Signature algorithm used for the delivery."
}
```

## Request body

```json
{
  "required": true,
  "content": {
    "application/json": {
      "schema": {
        "type": "object",
        "required": [
          "id",
          "timestamp",
          "type",
          "data"
        ],
        "properties": {
          "id": {
            "$ref": "#/components/schemas/EventId"
          },
          "timestamp": {
            "$ref": "#/components/schemas/EventTimestamp"
          },
          "type": {
            "type": "string",
            "const": "subscription.test"
          },
          "data": {
            "type": "object",
            "required": [
              "test"
            ],
            "properties": {
              "test": {
                "type": "string",
                "const": "OK",
                "description": "Test delivery marker."
              }
            }
          }
        }
      }
    }
  }
}
```

## Responses

### 200

```json
{
  "description": "Acknowledged by your endpoint."
}
```

## Operation metadata

```json
{
  "tags": [
    "Webhook subscription"
  ],
  "operationId": "onSubscriptionTest"
}
```

## Referenced definitions

- [`#/components/parameters/WebhookSignature`](#definition-1)
- [`#/components/parameters/WebhookKeyId`](#definition-2)
- [`#/components/parameters/WebhookAlgorithm`](#definition-3)
- [`#/components/schemas/EventId`](#definition-4)
- [`#/components/schemas/EventTimestamp`](#definition-5)

### definition-1

`#/components/parameters/WebhookSignature`

```json
{
  "name": "X-Signature",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string"
  },
  "description": "Ed25519 signature of the raw request body."
}
```

### definition-2

`#/components/parameters/WebhookKeyId`

```json
{
  "name": "X-Key-Id",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string",
    "format": "uuid"
  },
  "description": "Identifier of the public key used to verify the delivery signature."
}
```

### definition-3

`#/components/parameters/WebhookAlgorithm`

```json
{
  "name": "X-Algorithm",
  "in": "header",
  "required": true,
  "schema": {
    "type": "string",
    "const": "Ed25519"
  },
  "description": "Signature algorithm used for the delivery."
}
```

### definition-4

`#/components/schemas/EventId`

```json
{
  "type": "string",
  "format": "uuid",
  "description": "Event ID. Use this for de-duplication.",
  "examples": [
    "f47ac10b-58cc-4372-a567-0e02b2c3d479"
  ]
}
```

### definition-5

`#/components/schemas/EventTimestamp`

```json
{
  "type": "string",
  "format": "date-time",
  "description": "Time Axiym created the event. Formatted in ISO 8601.",
  "examples": [
    "2026-09-07T10:07:30Z"
  ]
}
```