## Mark messages as read

`POST /v1/chats/messages/read`

Marks the listed messages as read. All the messages must belong to one chat; the chat is determined from them, so no `dialogId` is needed.

## Request body fields

| Field | Type | Required | Description |
|------|-----|:-----:|---------|
| `ids` | number[] | yes | From 1 to 100 IDs of messages in one chat — numbers or digit strings. The IDs come from the [chat feed](/docs/chats/messages/list) (`GET /v1/chats/:dialogId/messages`) |

Other body fields and query parameters are rejected with `400 INVALID_PARAMS`.

## Examples

### curl — personal key

```bash
curl -X POST https://vibecode.bitrix24.com/v1/chats/messages/read \
  -H "X-Api-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "ids": [1001, 1002] }'
```

### curl — OAuth application

```bash
curl -X POST https://vibecode.bitrix24.com/v1/chats/messages/read \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{ "ids": [1001, 1002] }'
```

### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/read', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({ ids: [1001, 1002] }),
})

const { data } = await res.json()
console.log('Unread remaining:', data.counter)
```

### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/read', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({ ids: [1001, 1002] }),
})

const { data } = await res.json()
console.log('Unread remaining:', data.counter)
```

## Response fields

| Field | Type | Description |
|------|-----|---------|
| `success` | boolean | Always `true` on success |
| `data.chatId` | number | ID of the chat the messages belong to |
| `data.lastId` | number | ID of the chat's last message |
| `data.counter` | number | Number of unread messages remaining after the operation |
| `data.viewedMessages` | array | IDs of the messages marked by this call |

## Response example

```json
{
  "success": true,
  "data": {
    "chatId": 42,
    "lastId": 1002,
    "counter": 0,
    "viewedMessages": [1001, 1002]
  }
}
```

## Error response example

422 — the messages belong to different chats:

```json
{
  "success": false,
  "error": {
    "code": "BITRIX_ERROR",
    "message": "MESSAGES_IN_DIFFERENT_CHAT_ERROR",
    "b24Code": "MESSAGES_IN_DIFFERENT_CHAT_ERROR"
  }
}
```

## Errors

| HTTP | Code | Description |
|------|-----|---------|
| 400 | `INVALID_PARAMS` | `ids` is missing or is not an array of 1 to 100 positive integers (the error names the index of the invalid element), or the request has an extra body field or a query parameter. Checked before any call to Bitrix24 |
| 422 | `BITRIX_ERROR` | Bitrix24 refused; the code is in `error.b24Code`: `MESSAGES_IN_DIFFERENT_CHAT_ERROR` — the messages belong to different chats, `MESSAGE_NOT_FOUND` — a message does not exist |
| 404 | `ENTITY_NOT_FOUND` | Bitrix24 returned the `NOT_FOUND` code; the Bitrix24 code is in `error.b24Code` |
| 403 | `BITRIX_ACCESS_DENIED` | The user has no access to the chat of the messages — Bitrix24 refused with the `ACCESS_DENIED` code |
| 403 | `SCOPE_DENIED` | The key is missing the `im` scope |
| 403 | `WRITE_BLOCKED_READONLY_KEY` | The key is in read-only mode |
| 401 | `TOKEN_MISSING` | The API key has no Bitrix24 tokens configured |

Full list of common API errors — [Errors](/docs/errors).

## See also

- [Mark as read](/docs/chats/messages/read)
- [Messages](/docs/chats/messages)
- [Read messages](/docs/chats/messages/list)
- [Chat discovery](/docs/chats/discovery)