Get a callback listener
# Get Registered Callback Listeners ### `GET /callbacks/{accountName}` Returns the endpoint URL of the callback listening service registered for a given account. ## HTTP Request GET [https://thingspace.verizon.com/api/fota/v2/callbacks/{accountName}](/docs/standard-apis/connectivity-management/api-endpoints/connectivity-callbacks/list-registered-callbacks/listregisteredcallbacks) ## Resource Path Parameters | Parameter Name | Data Type | Description | |:----------------|:-----------|:-------------| | **accountName** <br> *required* | string | The name of the account for which a list of registered callback services will be returned. An account name is usually numeric, and must include any leading zeros. | ## Header Parameters The request header must contain a current ThingSpace authorization token and a current VZ-M2M session token. For more details on how to get these tokens, visit [Getting Started](https://thingspace.verizon.com/documentation/api-documentation.html#/http/session-management/guides/getting-started). | Parameter Name | Data Type | Description | |:-----------------------|:-----------|:-----------------------------------------------------------------------------| | **Authorization** <br> _required_ | string | HTTP Authorization bearer token: <br> `Authorization: Bearer {token}` | | **VZ-M2M-Token** <br> _required_ | string | A valid session token: <br> `VZ-M2M-Token: {M2Mtoken}` | ## Request Body None. ## Success Responses **Status 200** | Parameter Name | Data Type | Description | |:----------------|:-----------|:-------------| | **url** | string | The address of the callback listening service where ThingSpace sends callback messages for the service type. | The response body will be empty if there are no callback services registered with the account. ## Example Success Response ```json { "url": "http://10.120.102.183:50559/CallbackListener/FirmwareServiceMessages.asmx" } ``` ## Failure Responses **Status 400** All error messages are returned in this format: ```json { "errorCode": "error code string", "errorMessage": "error message string" } ``` Error codes and messages are listed on the Error Messages page, along with explanations and suggestions for corrective actions.