> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.tryenvoy.ai/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.tryenvoy.ai/_mcp/server.

# Initiate an ELP assessment call

POST https://tryenvoy.ai/api/v1/elp/tests
Content-Type: application/json

Place an outbound call to a driver and run the FMCSA-aligned English Language Proficiency assessment. Creates an ELP test record in REQUESTED state, places the call, and links the two. Poll `GET /v1/elp/tests/{test_id}` to follow the test through to scoring.

**Authentication:** Supports API key and bearer token authentication.

Reference: https://docs.tryenvoy.ai/api-reference/endpoints/elp/create-test

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Servers

- `https://tryenvoy.ai/api/v1` (Production, default)
- `https://staging.tryenvoy.ai/api/v1` (Staging)

## Request

### Headers

- `X-Organization-ID` (string, optional, nullable)
- `Idempotency-Key` (string, optional) — A unique key (up to 255 printable ASCII characters, e.g. a UUID) that makes a retry of this request safe. Envoy stores the response for 24 hours; a retry with the same key and the same request returns it again with `Idempotent-Replayed: true` instead of running twice. The same key with a different request returns 422 `idempotency_key_reused`; while the first request is still running, 409 `idempotency_key_in_progress`. 5xx and 429 responses are not stored.

### Body (application/json)

This endpoint expects an ELPTestCreateRequest.

- `phone_number` (string, required) — Driver phone number to call (E.164 format)

## Response

### 201

Successful Response

- `id` (string, required)
- `status` (enum, required) — Lifecycle state of an ELP test. Tracks *whether* the test ran, not its outcome quality. Outcome quality lives in the per-competency scores and the question counters (questions_answered, valid_answers). The system never renders a pass/fail verdict.
  - Allowed values: `REQUESTED`, `COMPLETED`, `FAILED`, `INCOMPLETE`
- `created_at` (datetime, required)
- `call_id` (string, optional, nullable)
- `carrier_id` (string, optional, nullable)
- `phone_number` (string, optional, nullable)
- `driver_name` (string, optional, nullable)
- `carrier_name` (string, optional, nullable)
- `mc_number` (string, optional, nullable)
- `scoring_status` (enum, optional, nullable) — Status of the post-call scoring pipeline.
  - Allowed values: `PENDING`, `SCORED`, `FAILED`
- `conversational_communication` (integer, optional, nullable)
- `instruction_comprehension` (integer, optional, nullable)
- `sign_recognition` (integer, optional, nullable)
- `verbal_reporting` (integer, optional, nullable)
- `total_score` (integer, optional, nullable)
- `total_questions` (integer, optional, nullable)
- `questions_answered` (integer, optional, nullable)
- `valid_answers` (integer, optional, nullable)
- `notes` (string, optional, nullable)
- `call` (ELPCallResponse, optional, nullable) — Associated phone call with transcript

## Errors

### 401 Unauthorized Error

Not authenticated - missing or invalid token/API key

- `any`

### 403 Forbidden Error

Insufficient permissions for this operation

- `any`

### 409 Conflict Error

`idempotency_key_in_progress`: a request with this Idempotency-Key is still running; retry later

- `any`

### 422 Unprocessable Entity Error

Validation Error; or `idempotency_key_reused`: this Idempotency-Key was already used for a different request

- `detail` (list of ValidationError, optional)

### 429 Too Many Requests Error

Rate limit exceeded - see Retry-After header

- `any`

## Types

### ELPCallResponse

Nested call object returned within an ELP test.

- `id` (string, required)
- `status` (string, required)
- `call_time` (datetime, required)
- `created_at` (datetime, required)
- `updated_at` (datetime, required)
- `call_direction` (string, optional, nullable)
- `phone_number` (string, optional, nullable) — Customer phone number
- `to_number` (string, optional, nullable)
- `from_number` (string, optional, nullable)
- `call_start_time` (datetime, optional, nullable)
- `call_end_time` (datetime, optional, nullable)
- `transcript` (list of TranscriptMessage, optional, nullable) — Call transcript

### ValidationError

- `loc` (list of ValidationErrorLocItems, required)
- `msg` (string, required)
- `type` (string, required)
- `input` (any, optional)
- `ctx` (ValidationErrorCtx, optional)

### TranscriptMessage

A single transcript message (role + content + optional tool metadata). extra='allow' preserves additional fields the voice pipeline may add (e.g., future metadata) without breaking validation.

- `role` (string, required)
- `content` (string, optional, nullable)
- `id` (string, optional, nullable)
- `timestamp` (string, optional, nullable)
- `interrupted` (boolean, optional, nullable)
- `transcript_confidence` (double, optional, nullable)
- `tool_calls` (list of TranscriptToolCall, optional, nullable)
- `tool_call_id` (string, optional, nullable)

### ValidationErrorLocItems

### ValidationErrorCtx

### TranscriptToolCall

A single tool call emitted by the LLM during a voice call.

- `id` (string, optional, default: )
- `type` (string, optional, default: )
- `function` (TranscriptToolCallFunction, optional, nullable) — The function invocation details within a tool call.

### TranscriptToolCallFunction

The function invocation details within a tool call.

- `name` (string, optional, default: )
- `arguments` (any, optional)

## Examples

**Request**

```json
{
  "phone_number": "string"
}
```

**Response**

```json
{
  "id": "elp_00000000-0000-0000-0000-000000000000",
  "status": "REQUESTED",
  "created_at": "2024-01-15T09:30:00Z",
  "call_id": "call_00000000-0000-0000-0000-000000000000",
  "carrier_id": "car_00000000-0000-0000-0000-000000000000",
  "phone_number": "string",
  "driver_name": "string",
  "carrier_name": "string",
  "mc_number": "string",
  "scoring_status": "PENDING",
  "conversational_communication": 1,
  "instruction_comprehension": 1,
  "sign_recognition": 1,
  "verbal_reporting": 1,
  "total_score": 1,
  "total_questions": 1,
  "questions_answered": 1,
  "valid_answers": 1,
  "notes": "string",
  "call": {
    "id": "call_00000000-0000-0000-0000-000000000000",
    "status": "string",
    "call_time": "2024-01-15T09:30:00Z",
    "created_at": "2024-01-15T09:30:00Z",
    "updated_at": "2024-01-15T09:30:00Z",
    "call_direction": "string",
    "phone_number": "string",
    "to_number": "string",
    "from_number": "string",
    "call_start_time": "2024-01-15T09:30:00Z",
    "call_end_time": "2024-01-15T09:30:00Z",
    "transcript": [
      {
        "role": "string",
        "content": "string",
        "id": "string",
        "timestamp": "string",
        "interrupted": true,
        "transcript_confidence": 1.1,
        "tool_calls": [
          {
            "id": "",
            "type": "",
            "function": {
              "name": "",
              "arguments": null
            }
          }
        ],
        "tool_call_id": "string"
      }
    ]
  }
}
```

**SDK Code**

```python
import requests

url = "https://tryenvoy.ai/api/v1/elp/tests"

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

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

print(response.json())
```

```javascript
const url = 'https://tryenvoy.ai/api/v1/elp/tests';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"phone_number":"string"}'
};

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://tryenvoy.ai/api/v1/elp/tests"

	payload := strings.NewReader("{\n  \"phone_number\": \"string\"\n}")

	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://tryenvoy.ai/api/v1/elp/tests")

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 = "{\n  \"phone_number\": \"string\"\n}"

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://tryenvoy.ai/api/v1/elp/tests")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"phone_number\": \"string\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://tryenvoy.ai/api/v1/elp/tests', [
  'body' => '{
  "phone_number": "string"
}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://tryenvoy.ai/api/v1/elp/tests");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"phone_number\": \"string\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

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

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

let request = NSMutableURLRequest(url: NSURL(string: "https://tryenvoy.ai/api/v1/elp/tests")! 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()
```