## Channel comments

A channel post may have a comment thread — a separate chat bound to the post. These calls read a summary of comment threads, mark all comments in a channel as read and enable or disable notifications about new comments on a post. The v2 messenger methods: `im.v2.Chat.Message.CommentInfo.list`, `im.v2.Chat.Comment.readAll`, `im.v2.Chat.Comment.subscribe` and `im.v2.Chat.Comment.unsubscribe`.

## Comment summary for posts

`GET /v1/chats/messages/comments`

For each post with a comment thread, returns its chat, the number of messages in it, the latest commenters and whether you follow the thread.

### Parameters

| Parameter | Type | Required | Default | Description |
|----------|-----|:-----:|-----------|---------|
| `messageIds` (query) | string | yes | — | Comma-separated IDs of 1 to 100 posts from one channel: `845,846` |

Any other parameter, or `messageIds` given more than once, is rejected with `400 INVALID_PARAMS`.

### Examples

#### curl — personal key

```bash
curl "https://vibecode.bitrix24.com/v1/chats/messages/comments?messageIds=845,846" \
  -H "X-Api-Key: YOUR_API_KEY"
```

#### curl — OAuth application

```bash
curl "https://vibecode.bitrix24.com/v1/chats/messages/comments?messageIds=845,846" \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN"
```

#### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/comments?messageIds=845,846', {
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Posts with comments:', data.commentInfo.map((c) => c.messageId))
```

#### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/comments?messageIds=845,846', {
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()
console.log('Posts with comments:', data.commentInfo.map((c) => c.messageId))
```

### Response fields

| Field | Type | Description |
|------|-----|---------|
| `success` | boolean | Always `true` on success |
| `data.commentInfo` | array | One item per post that has a comment thread |
| `data.commentInfo[].messageId` | number | Post ID |
| `data.commentInfo[].chatId` | number | ID of the comment chat |
| `data.commentInfo[].dialogId` | string | Dialog ID of the comment chat, `chatN` |
| `data.commentInfo[].messageCount` | number | Number of messages in the thread. A thread opens with a system message, so a thread without comments shows `1` here |
| `data.commentInfo[].lastUserIds` | array | IDs of the latest commenters |
| `data.commentInfo[].isUserSubscribed` | boolean | Whether you follow the post's comments |
| `data.usersShort` | array | Brief details of the commenters: `id`, `name`, `avatar`, `color`, `type` |

### Response example

```json
{
  "success": true,
  "data": {
    "commentInfo": [
      {
        "chatId": 2001,
        "dialogId": "chat2001",
        "messageId": 845,
        "lastUserIds": [7],
        "messageCount": 3,
        "isUserSubscribed": true
      }
    ],
    "usersShort": [
      { "id": 7, "name": "Anna Smith", "avatar": "", "color": "#df532d", "type": "user" }
    ]
  }
}
```

## Mark all channel comments as read

`POST /v1/chats/:dialogId/comments/read-all`

Marks all comments on all posts in the channel as read for you.

### Parameters

| Parameter | Type | Required | Default | Description |
|----------|-----|:-----:|-----------|---------|
| `dialogId` (path) | string | yes | — | Dialog ID of the channel, `chatXXX` |

No body is needed. Query parameters and body fields are rejected with `400 INVALID_PARAMS`.

### Examples

#### curl — personal key

```bash
curl -X POST "https://vibecode.bitrix24.com/v1/chats/chat2000/comments/read-all" \
  -H "X-Api-Key: YOUR_API_KEY"
```

#### curl — OAuth application

```bash
curl -X POST "https://vibecode.bitrix24.com/v1/chats/chat2000/comments/read-all" \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN"
```

#### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/chat2000/comments/read-all', {
  method: 'POST',
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Comments marked as read:', data.result)
```

#### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/chat2000/comments/read-all', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()
console.log('Comments marked as read:', data.result)
```

## Follow post comments

`POST /v1/chats/messages/:messageId/comments/subscription`

Turns on notifications about new comments on the post.

### Parameters

| Parameter | Type | Required | Default | Description |
|----------|-----|:-----:|-----------|---------|
| `messageId` (path) | number | yes | — | ID of the channel post, a positive integer |

No body is needed. Query parameters and body fields are rejected with `400 INVALID_PARAMS`.

### Examples

#### curl — personal key

```bash
curl -X POST "https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription" \
  -H "X-Api-Key: YOUR_API_KEY"
```

#### curl — OAuth application

```bash
curl -X POST "https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription" \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN"
```

#### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription', {
  method: 'POST',
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Notifications on:', data.result)
```

#### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()
console.log('Notifications on:', data.result)
```

## Stop following post comments

`DELETE /v1/chats/messages/:messageId/comments/subscription`

Turns off notifications about new comments on the post.

### Parameters

| Parameter | Type | Required | Default | Description |
|----------|-----|:-----:|-----------|---------|
| `messageId` (path) | number | yes | — | ID of the channel post, a positive integer |

No body is needed. Query parameters and body fields are rejected with `400 INVALID_PARAMS`.

### Examples

#### curl — personal key

```bash
curl -X DELETE "https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription" \
  -H "X-Api-Key: YOUR_API_KEY"
```

#### curl — OAuth application

```bash
curl -X DELETE "https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription" \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN"
```

#### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription', {
  method: 'DELETE',
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Notifications off:', data.result)
```

#### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/845/comments/subscription', {
  method: 'DELETE',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()
console.log('Notifications off:', data.result)
```

### Response

Marking all comments as read, following and unfollowing return the same response:

```json
{
  "success": true,
  "data": { "result": true }
}
```

## Error response example

422 — the message is not a channel post:

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

## Errors

| HTTP | Code | Description |
|------|-----|---------|
| 400 | `INVALID_PARAMS` | `messageId` is not a positive integer; for the summary — `messageIds` is missing, empty, has more than 100 items, has an item that is not a positive integer, is given more than once, or another parameter is given; for the other calls — any query parameter or body field. Checked before any call to Bitrix24 |
| 404 | `ENTITY_NOT_FOUND` | Bitrix24 returned "not found"; the portal code is in `error.b24Code` |
| 422 | `BITRIX_ERROR` | Bitrix24 returned an error; the portal code is in `error.b24Code`. `WRONG_MESSAGE_TYPE` — the chat is not a channel; `WRONG_PARENT_CHAT` — the message is not a channel post; `MESSAGES_IN_DIFFERENT_CHAT_ERROR` — the posts belong to different channels |
| 403 | `SCOPE_DENIED` | The API key does not have the `im` scope |
| 403 | `WRITE_BLOCKED_READONLY_KEY` | The key is read-only: marking all comments as read, following and unfollowing change data — see [access rights](/docs/access-rights). The summary stays a read |
| 401 | `TOKEN_MISSING` | The API key has no Bitrix24 tokens configured |
| 502 | `ME_ALIAS_RESOLUTION_FAILED` | Could not resolve the current user for `dialogId` = `me` |

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

## Known specifics

**Following means notifications, not events.** Following turns on notifications about new comments. It does not deliver comments in real time — for that, [subscribe to events](/docs/chats/events/subscribe).

**The thread appears together with the post.** Bitrix24 opens a thread as soon as a post is sent to the channel, before the first comment. A forwarded post has no thread; for such a post, following and unfollowing create one — the Bitrix24 messenger does the same. So the call works on any channel post.

**Unfollowing marks the thread as read.** When you unfollow a post, Bitrix24 also marks its comments as read for you.

**The summary covers posts with a thread only.** A post without a thread, such as a forwarded one, does not appear in `data.commentInfo`. All `messageIds` must belong to the same channel.

## See also

- [Messages around a message](/docs/chats/messages/context)
- [Subscribe to events](/docs/chats/events/subscribe)