# Fetch one group challenge

- Endpoint: `GET /v1/{organizationId}/group-challenge/{challengeId}`
- Production: `https://api.main-team.org/v1/{organizationId}/group-challenge/{challengeId}`
- Sandbox: `https://apisnd.main-team.org/v1/{organizationId}/group-challenge/{challengeId}`
- Operation: `getGroupChallenge` (Group challenges)
- Authentication: `Authorization: Bearer <token>`, a short-lived token you sign with your API key and secret
- Permission: `group-challenge/read:$org:$ID`

## Description

Reads one group challenge of this organization: its dates, how many students a group takes, the grade groups it is open to and the steps a group works through, in order.

## Parameters

| Name | In | Required | Type | Description |
| --- | --- | --- | --- | --- |
| `organizationId` | path | yes | string | The organization’s `_id`: 24 hexadecimal digits, as `listOrganizations` (`GET /v1/organization`) lists it. |
| `challengeId` | path | yes | string | The group challenge’s `_id`, from `listGroupChallenges`. |

## Response

`200` Success: `message` is "Group challenge fetched successfully.".

```json
{
  "success": true,
  "message": "Group challenge fetched successfully.",
  "pagination": {
    "page": 1,
    "limit": 20,
    "total": 57,
    "totalPages": 3
  },
  "data": {
    "_id": "6650a1b2c3d4e5f6a7b8c9eb",
    "name": "STEM Maker Challenge",
    "status": "published",
    "isOpen": true,
    "windowStart": "2026-10-01T00:00:00.000Z",
    "windowEnd": "2026-12-21T23:59:59.999Z",
    "minStudents": 2,
    "maxStudents": 3,
    "isPaid": false,
    "gradeGroups": [
      {
        "_id": "6650a1b2c3d4e5f6a7b8c9ec",
        "label": "Group 7-8-9",
        "grades": [
          {
            "_id": "6650a1b2c3d4e5f6a7b8c9d4",
            "name": "10"
          }
        ]
      }
    ],
    "steps": [
      {
        "_id": "6650a1b2c3d4e5f6a7b8c9ee",
        "order": 1,
        "title": "Project proposal",
        "fileTypes": [
          "pdf",
          "docx"
        ],
        "maxFileBytes": 20971520,
        "maxFiles": 1
      }
    ]
  }
}
```

## Errors

| Status | Code | When |
| --- | --- | --- |
| 400 | [`bad_request`](https://hub.main-team.org/api/errors#bad_request) | `challengeId` is not 24 hexadecimal digits. |
| 401 | [`unauthorized`](https://hub.main-team.org/api/errors#unauthorized) | The token is missing or malformed, is not signed with your account’s `apiSecret`, breaks the `iat` and `exp` rules, has expired or been revoked, or its account is not active. All of these answer the same. |
| 403 | [`forbidden`](https://hub.main-team.org/api/errors#forbidden) | The token is valid, but no role on your account allows `group-challenge/read` on the organization in the path, or a role denies it. |
| 404 | [`not_found`](https://hub.main-team.org/api/errors#not_found) | `organizationId` is not the `_id` of an organization. |
| 404 | [`not_found`](https://hub.main-team.org/api/errors#not_found) | Group challenges are not switched on for this organization. The answer is the one an unknown path gets; nothing was read. |
| 404 | [`not_found`](https://hub.main-team.org/api/errors#not_found) | No group challenge of this organization has this id, or it is not published: a draft, archived or deleted challenge answers the same. |
| 429 | [`too_many_requests`](https://hub.main-team.org/api/errors#too_many_requests) | Your account has made more than 100 requests to this operation in the current 60-second window. Wait the seconds in `Retry-After` before sending again. |
| 500 | [`internal_error`](https://hub.main-team.org/api/errors#internal_error) | Something failed on our side. Retry later, and quote `request_id` if it goes on. |

## Code samples

### curl

```bash
# $TOKEN: a short-lived token you minted with your API key and secret
curl -sS 'https://api.main-team.org/v1/<organizationId>/group-challenge/<challengeId>' \
  -H "Authorization: Bearer $TOKEN"
```

### Node.js

```js
const token = process.env.TOKEN; // a short-lived token you minted with your API key and secret

const res = await fetch('https://api.main-team.org/v1/<organizationId>/group-challenge/<challengeId>', {
  headers: {
    Authorization: `Bearer ${token}`,
  },
});
const body = await res.json();
if (!res.ok) throw new Error(`${res.status} ${body.error.code}: ${body.error.message}`);
console.log(body.data);
```

### PHP

```php
<?php
$token = getenv('TOKEN'); // a short-lived token you minted with your API key and secret

$ch = curl_init('https://api.main-team.org/v1/<organizationId>/group-challenge/<challengeId>');
curl_setopt_array($ch, [
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer ' . $token,
    ],
    CURLOPT_RETURNTRANSFER => true,
]);
$response = curl_exec($ch);
if ($response === false) {
    throw new RuntimeException(curl_error($ch));
}
$status = curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
$body = json_decode($response, true);
if ($status >= 400) {
    $error = $body['error'];
    throw new RuntimeException("$status {$error['code']}: {$error['message']}");
}
print_r($body['data']);
```