> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> STT). Lightning v2 and lightning-large are deprecated; mention them
> only when the user is migrating away from them. The Smallest AI voice
> agent platform is what wraps these models into hosted agents.

# Start a test call against a branch

POST https://api.smallest.ai/atoms/v1/agent/{id}/branches/{branchId}/test-call
Content-Type: application/json

Start a test call using the branch's current config. Send `includeDraft: true` to test the open draft, or send `revisionId` to test a specific committed revision on the branch. Sending both is a validation error.

The response always includes `conversationId` and `callId`. For `webcall` and `chat`, it also includes `token`, `roomName`, and `host`. Those fields are omitted for `telephony`.


Reference: https://docs.smallest.ai/voice-agents/api-reference/agent-versioning-branches/test-call

## OpenAPI Specification

```yaml
openapi: 3.1.0
info:
  title: atoms
  version: 1.0.0
paths:
  /agent/{id}/branches/{branchId}/test-call:
    post:
      operationId: test-call
      summary: Start a test call against a branch
      description: >
        Start a test call using the branch's current config. Send `includeDraft:
        true` to test the open draft, or send `revisionId` to test a specific
        committed revision on the branch. Sending both is a validation error.


        The response always includes `conversationId` and `callId`. For
        `webcall` and `chat`, it also includes `token`, `roomName`, and `host`.
        Those fields are omitted for `telephony`.
      tags:
        - agentVersioningBranches
      parameters:
        - name: id
          in: path
          description: The agent ID.
          required: true
          schema:
            type: string
        - name: branchId
          in: path
          description: The branch ID.
          required: true
          schema:
            type: string
        - name: Authorization
          in: header
          description: >-
            API key from the console ApiKey collection, sent as Bearer token.
            Also accepts session cookies for browser-based auth.
          required: true
          schema:
            type: string
      responses:
        '200':
          description: Test call initiated.
          content:
            application/json:
              schema:
                $ref: >-
                  #/components/schemas/agent_versioning_branches_test_call_Response_200
        '400':
          description: Invalid input
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BadRequestErrorResponse'
        '401':
          description: Unauthorized access
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UnauthorizedErrorResponse'
        '403':
          description: >-
            Forbidden. Returned for workflow_graph agents when the organization
            lacks conversational agents access.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiResponse'
        '404':
          description: >-
            Branch, agent, or referenced revision not found. Also returned when
            `includeDraft: true` is sent and no draft is open.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BadRequestErrorResponse'
        '409':
          description: The branch has no committed revision to test against.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ConflictErrorResponse'
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/InternalServerErrorResponse'
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/TestCallV2Request'
servers:
  - url: https://api.smallest.ai/atoms/v1
    description: Production server
components:
  schemas:
    TestCallV2RequestMode:
      type: string
      enum:
        - webcall
        - chat
        - telephony
      default: webcall
      title: TestCallV2RequestMode
    TestCallV2Request:
      type: object
      properties:
        includeDraft:
          type: boolean
          default: false
          description: >-
            When `true`, the test call uses the branch's open draft. Mutually
            exclusive with `revisionId`.
        revisionId:
          type: string
          description: >-
            Test against a specific committed revision on the branch. Mutually
            exclusive with `includeDraft: true`.
        mode:
          $ref: '#/components/schemas/TestCallV2RequestMode'
          default: webcall
        toPhone:
          type: string
          description: >-
            E.164-formatted number. Required when `mode` is `telephony`. Omit
            for `webcall` and `chat`.
      description: >
        Body for `POST /agent/{id}/branches/{branchId}/test-call`. When both
        `includeDraft` and `revisionId` are omitted, the branch's committed head
        is used.
      title: TestCallV2Request
    TestCallResult:
      type: object
      properties:
        conversationId:
          type: string
        callId:
          type: string
        token:
          type: string
          description: LiveKit access token. Returned for `webcall` and `chat` modes only.
        roomName:
          type: string
          description: Returned for `webcall` and `chat` modes only.
        host:
          type: string
          description: Returned for `webcall` and `chat` modes only.
      required:
        - conversationId
        - callId
      description: Returned by `POST /agent/{id}/branches/{branchId}/test-call`.
      title: TestCallResult
    agent_versioning_branches_test_call_Response_200:
      type: object
      properties:
        status:
          type: boolean
        data:
          $ref: '#/components/schemas/TestCallResult'
      title: agent_versioning_branches_test_call_Response_200
    BadRequestErrorResponse:
      type: object
      properties:
        status:
          type: boolean
        errors:
          type: array
          items:
            type: string
      title: BadRequestErrorResponse
    UnauthorizedErrorResponse:
      type: object
      properties:
        status:
          type: boolean
        errors:
          type: array
          items:
            type: string
      title: UnauthorizedErrorResponse
    ApiResponseData:
      type: object
      properties: {}
      title: ApiResponseData
    ApiResponse:
      type: object
      properties:
        status:
          type: boolean
        data:
          $ref: '#/components/schemas/ApiResponseData'
      title: ApiResponse
    ConflictErrorResponse:
      type: object
      properties:
        status:
          type: boolean
        error_type:
          type: string
        errors:
          type: array
          items:
            type: string
      description: >
        Generic conflict body. `error_type` is a stable machine-readable
        discriminator (for example `branch_name_exists`, `source_has_no_commit`,
        `source_scanning`, `publish_in_progress`, `no_committed_revision`).
      title: ConflictErrorResponse
    InternalServerErrorResponse:
      type: object
      properties:
        status:
          type: boolean
        errors:
          type: array
          items:
            type: string
      title: InternalServerErrorResponse
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      description: >-
        API key from the console ApiKey collection, sent as Bearer token. Also
        accepts session cookies for browser-based auth.

```

## Examples



**Request**

```json
{}
```

**Response**

```json
{
  "status": true,
  "data": {
    "conversationId": "5f8d04b2a1c2e3001a2b3c4d",
    "callId": "6a7b8c9d0e1f23456789abcd",
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9",
    "roomName": "support_room_42",
    "host": "livekit.smallest.ai"
  }
}
```

**SDK Code**

```python
import requests

url = "https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call"

payload = {}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call"

	payload := strings.NewReader("{}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{}"

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call', [
  'body' => '{}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = [] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://api.smallest.ai/atoms/v1/agent/id/branches/branchId/test-call")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```