An Application is a named container for the webhook URLs that control your call flow. You attach a phone number or a SIP endpoint to an application so that calls fire its configured webhooks. See Application vs Endpoint below to choose the right object.
Attributes
| Field | Type | Description |
|---|
app_id | string | Unique identifier for the application. Use it in all per-application API paths. |
app_name | string | Name of the application. |
answer_url | string | URL Vobiz fetches when a call executes this application. Must return valid VobizXML to control the call flow. |
answer_method | string | HTTP method for answer_url. One of GET or POST. Default POST. |
hangup_url | string | URL notified when the call ends. Useful for analytics and cleanup. If unset at create time, defaults to answer_url. |
hangup_method | string | HTTP method for hangup_url. One of GET or POST. Default POST. |
fallback_answer_url | string (nullable) | Backup URL invoked only when answer_url is unreachable, times out, or returns invalid VobizXML. Must itself return valid VobizXML. null when unset. |
fallback_method | string | HTTP method for fallback_answer_url. One of GET or POST. Default POST. |
message_url | string (nullable) | URL notified when an inbound message is received. Vobiz expects an HTTP 200 response. null when unset. |
message_method | string | HTTP method for message_url. One of GET or POST. Default POST. |
default_number_app | boolean | If true, newly created numbers without an app_id are auto-routed to this application. Default false. Does not retroactively re-route existing numbers. |
default_endpoint_app | boolean | If true, newly created endpoints without an application are auto-routed to this application. Default false. Does not retroactively re-route existing endpoints. |
sub_account | string (nullable) | Sub-account auth_id. null for the main account. Cannot be changed after creation. |
resource_uri | string | API resource URI for this application. |
application_type | string | Type of application. Typically XML (also seen as voice). |
default_app | boolean | Whether this is the account-level default application. Default false. |
enabled | boolean | Whether the application is enabled. Default true. |
log_incoming_message | boolean | Whether incoming messages to numbers on this application are logged. Default true. |
public_uri | boolean | Whether the application’s sip_uri is reachable by external SIP systems. Default false. See Public SIP URI. |
sip_transfer_method | string | HTTP method for SIP transfer callbacks. One of GET or POST. |
sip_transfer_url | string (nullable) | URL notified during a SIP transfer. null when unset. |
sip_uri | string | SIP URI associated with the application, e.g. sip:<app_id>@sip.vobiz.ai. |
created_at | string (ISO 8601) | Creation timestamp (UTC). |
updated_at | string (ISO 8601) | Last update timestamp (UTC). |
api_id is a request-correlation ID returned alongside the object on single-object responses (Create, Retrieve, Update). It is not a persistent attribute of the application.
Example Application Object
{
"answer_method": "POST",
"answer_url": "https://example.com/answer",
"api_id": "aabbccdd-1234-5678-90ab-cdef12345678",
"app_id": "12345678901234567",
"app_name": "My Voice App",
"application_type": "XML",
"created_at": "2026-04-02 12:11:19.740666+00:00",
"default_app": false,
"default_endpoint_app": false,
"enabled": true,
"fallback_answer_url": null,
"fallback_method": "POST",
"hangup_method": "POST",
"hangup_url": "https://example.com/hangup",
"log_incoming_message": true,
"message_method": "POST",
"message_url": null,
"public_uri": false,
"resource_uri": "/v1/Account/MA_XXXXXXXX/Application/12345678901234567/",
"sip_transfer_method": "POST",
"sip_transfer_url": null,
"sip_uri": "sip:12345678901234567@app.vobiz.ai",
"sub_account": null,
"updated_at": "2026-04-02 12:11:19.740666+00:00"
}
Application vs Endpoint
| You want to… | Use |
|---|
| Route inbound calls on a phone number (DID) to your webhooks | An Application, then attach the number to it. |
| Let a device or person (browser, softphone, desk phone, AI agent) place and receive calls | An Endpoint, with an Application attached for its call logic. |
| Both - a number rings, then routes to a device | A number attached to an Application whose VobizXML Dials the endpoint’s sip_uri. |
Public SIP URI
Every application has a sip_uri such as sip:<app_id>@sip.vobiz.ai. By default public_uri is false, meaning the URI is not exposed to external SIP systems.
Set public_uri: true only when a third-party SIP system - for example another PBX or carrier - needs to route calls directly into this application’s sip_uri. For ordinary inbound flows driven by a Vobiz phone number, leave public_uri as false. 
