# Link one of your students to a supervisor on this organization

- Endpoint: `PUT /v1/{organizationId}/student/{studentId}/supervisor`
- Production: `https://api.main-team.org/v1/{organizationId}/student/{studentId}/supervisor`
- Sandbox: `https://apisnd.main-team.org/v1/{organizationId}/student/{studentId}/supervisor`
- Operation: `linkStudentSupervisor` (Students)
- Authentication: `Authorization: Bearer <token>`, a short-lived token you sign with your API key and secret
- Permission: `student/update:$org:$ID`

## Description

Attaches the student to a supervisor of this organization, found by `supervisorUsername`. Any supervisor of this organization can be linked.

**The link is made on this organization only.** Each organization keeps its own record of a student and the link is written there, so the student’s records on other organizations are left as they were. Neither `getStudent` nor `getOrgStudent` shows it: both read the record you registered. The link stays when the student signs in again. Linking another supervisor replaces the first on this organization, and repeating a link changes nothing.

**The student has to have signed in to this organization once**, with a link from `createSigninLink`. That first sign-in is when the organization creates its record of them, and before it there is nothing to link.

**Every refusal is the same 404, `Not found!`:** a student who is not yours, a student this organization has no record of yet, a username nobody has here, and one whose owner is not a supervisor here. The answer never says which, and never repeats the username. A malformed `studentId`, or a `supervisorUsername` that is missing or empty, is a 400; one of spaces only is the 404.

Answers with the organization’s `slug`; this organization’s record of the student after the link, whose `_id` is this organization’s own id for the student and whose `mainId` is the id you use everywhere else; and the supervisor’s id and username.

## Parameters

| Name | In | Required | Type | Description |
| --- | --- | --- | --- | --- |
| `organizationId` | path | yes | string | The organization’s `_id`: 24 hexadecimal digits, as `listOrganizations` (`GET /v1/organization`) lists it. |
| `studentId` | path | yes | string | The student’s id (`_id`), as `registerStudent` returned it. |

## Request body

Required fields: `supervisorUsername`.

```json
{
  "supervisorUsername": "XXT1003"
}
```

## Response

`200` Success: `message` is "Student linked to supervisor successfully.".

```json
{
  "success": true,
  "message": "Student linked to supervisor successfully.",
  "pagination": {
    "page": 1,
    "limit": 20,
    "total": 57,
    "totalPages": 3
  },
  "data": {
    "organization": "stem",
    "student": {
      "_id": "6650a1b2c3d4e5f6a7b8c9d0",
      "mainId": "6650a1b2c3d4e5f6a7b8c9d0",
      "username": "XXB1045",
      "firstName": "Jane",
      "lastName": "Doe",
      "fullName": "Jane Doe",
      "email": "jane.doe@example.com",
      "emailConfirmed": false,
      "phone": "+1 555 0100",
      "birth": "14/05/2008",
      "sex": "f",
      "country": "6650a1b2c3d4e5f6a7b8c9d1",
      "city": "6650a1b2c3d4e5f6a7b8c9d2",
      "school": "6650a1b2c3d4e5f6a7b8c9d3",
      "grade": "6650a1b2c3d4e5f6a7b8c9d4",
      "supervisor": "6650a1b2c3d4e5f6a7b8c9d5",
      "partner": "6650a1b2c3d4e5f6a7b8c9d6",
      "activatedPlatformsThisSeason": [
        "common"
      ],
      "createdAt": "2026-09-01T09:30:00.000Z",
      "updatedAt": "2026-09-02T14:05:00.000Z"
    },
    "supervisor": {
      "_id": "6650a1b2c3d4e5f6a7b8c9d5",
      "username": "XXT1003"
    }
  }
}
```

## Errors

| Status | Code | When |
| --- | --- | --- |
| 400 | [`bad_request`](https://hub.main-team.org/api/errors#bad_request) | The body is not valid JSON, breaks a field’s rules, or has a field this operation does not accept ("property <name> should not exist"). |
| 400 | [`bad_request`](https://hub.main-team.org/api/errors#bad_request) | `studentId` is not a well-formed id. |
| 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 `student/update` 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) | Any refusal: the student is not yours, this organization has no record of them yet (they have never signed in to it), or no supervisor of this organization has this username. |
| 413 | [`payload_too_large`](https://hub.main-team.org/api/errors#payload_too_large) | The body is larger than 100 kB. |
| 415 | [`unsupported_media_type`](https://hub.main-team.org/api/errors#unsupported_media_type) | The body declares a charset that is not a UTF one (send UTF-8), or a `Content-Encoding` other than gzip, deflate or br. |
| 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 -X PUT 'https://api.main-team.org/v1/<organizationId>/student/<studentId>/supervisor' \
  -H "Authorization: Bearer $TOKEN" \
  -H 'Content-Type: application/json' \
  --data-binary @- <<'JSON'
{
  "supervisorUsername": "XXT1003"
}
JSON
```

### 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>/student/<studentId>/supervisor', {
  method: 'PUT',
  headers: {
    Authorization: `Bearer ${token}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "supervisorUsername": "XXT1003"
  }),
});
const body = await res.json();
if (!res.ok) throw new Error(`${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

$ch = curl_init('https://api.main-team.org/v1/<organizationId>/student/<studentId>/supervisor');
curl_setopt_array($ch, [
    CURLOPT_CUSTOMREQUEST => 'PUT',
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer ' . $token,
        'Content-Type: application/json',
    ],
    CURLOPT_POSTFIELDS => json_encode([
        'supervisorUsername' => 'XXT1003',
    ]),
    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']);
```