## Open the discussion of a post `POST /v1/chats/messages/:messageId/comments/chat` Opens the comment chat of a channel post in one request. The response is the same as for [loading a chat](/docs/chats/messages/load): the chat card, the first page of messages, pinned messages, participants and files. If the post has no comment chat yet, Bitrix24 creates it. You become a participant of this chat. ## Parameters | Parameter | Type | Required | Default | Description | |----------|-----|:-----:|-----------|---------| | `messageId` (path) | number | yes | — | ID of the channel post, a positive integer. Posts of a channel — [Read messages](/docs/chats/messages/list) | | `messageLimit` (query) | number | no | 50 | How many messages to take on each side of the pivot message: the page holds up to `messageLimit` messages before it, the message itself and up to `messageLimit` after. From 1 to 200: a value outside the range is clamped; the passed and applied values are in `meta.requestedMessageLimit` and `meta.appliedMessageLimit` | | `pinLimit` (query) | number | no | 50 | How many pinned messages to return. From 1 to 200; the passed and applied values are in `meta.requestedPinLimit` and `meta.appliedPinLimit` | | `ignoreMark` (query) | boolean | no | `false` | `true` — build the first page from the last read message, ignoring the "unread" mark | No body is needed. Other parameters, repeated 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/chat?messageLimit=30" \ -H "X-Api-Key: YOUR_API_KEY" ``` ### curl — OAuth application ```bash curl -X POST "https://vibecode.bitrix24.com/v1/chats/messages/845/comments/chat?messageLimit=30" \ -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/chat?messageLimit=30', { method: 'POST', headers: { 'X-Api-Key': 'YOUR_API_KEY' }, }) const { data } = await res.json() console.log('Comment chat:', data.chat.dialogId) console.log('Comments:', data.messages.length) ``` ### JavaScript — OAuth application ```javascript const res = await fetch('https://vibecode.bitrix24.com/v1/chats/messages/845/comments/chat?messageLimit=30', { method: 'POST', headers: { 'X-Api-Key': 'YOUR_APP_KEY', 'Authorization': 'Bearer USER_SESSION_TOKEN', }, }) const { data } = await res.json() console.log('Comment chat:', data.chat.dialogId) console.log('Comments:', data.messages.length) ``` ## Response fields | Field | Type | Description | |------|-----|---------| | `success` | boolean | Always `true` on success | | `data.chat` | object | The comment chat card: `id`, `dialogId`, `name`, `type`, `owner`, `role` and other fields, as for [loading a chat](/docs/chats/messages/load) | | `data.messages` | array | The first page of messages of the comment chat | | `data.pins` | array | Pinned messages | | `data.users` | array | Participants mentioned on the page | | `data.files` | array | Files attached to the messages on the page | | `data.reactions` | array | Reactions to the messages on the page | | `data.hasPrevPage` | boolean | Whether there are messages older than the first page | | `data.hasNextPage` | boolean | Whether there are messages newer than the first page | | `meta.requestedMessageLimit` | number | The passed `messageLimit` value, present when it falls outside the range from 1 to 200 | | `meta.appliedMessageLimit` | number | The applied `messageLimit` value — only when it was clamped to a bound | | `meta.requestedPinLimit` | number | The passed `pinLimit` value, present when it falls outside the range from 1 to 200 | | `meta.appliedPinLimit` | number | The applied `pinLimit` value — only when it was clamped to a bound | ## Response example ```json { "success": true, "data": { "chat": { "id": 2001, "dialogId": "chat2001", "name": "Post comments", "type": "comment", "owner": 5, "role": "member" }, "messages": [ { "id": 3002, "chatId": 2001, "authorId": 7, "date": "2026-10-29T10:01:00+00:00", "text": "Agreed", "params": {} } ], "pins": [], "users": [], "files": [], "reactions": [], "hasPrevPage": false, "hasNextPage": false } } ``` ## Error response example 403 — a request with a read-only key: ```json { "success": false, "error": { "code": "WRITE_BLOCKED_READONLY_KEY", "message": "Key is in read-only mode. Switch the key to read and write in /keys to allow Bitrix24 data changes.", "details": { "method": "im.v2.Chat.load", "keyName": "Reports dashboard", "currentMode": "READONLY", "switchUrl": "/keys" } } } ``` ## Errors | HTTP | Code | Description | |------|-----|---------| | 400 | `INVALID_PARAMS` | `messageId` is not a positive integer, or the request has a parameter other than `messageLimit`, `pinLimit` and `ignoreMark`, a repeated parameter, an invalid value, a body that is not a JSON object, or a body field. Checked before any call to Bitrix24 | | 404 | `ENTITY_NOT_FOUND` | Bitrix24 returned a generic "not found" code or an error with the text "not found". The portal code is in `error.b24Code` | | 422 | `BITRIX_ERROR` | Bitrix24 returned an error, the portal code is in `error.b24Code`. A missing message lands here too — with `MESSAGE_NOT_FOUND`, not with a `404` | | 403 | `BITRIX_ACCESS_DENIED` | The user has no access to the chat — Bitrix24 refused with the `ACCESS_DENIED` code | | 403 | `SCOPE_DENIED` | The API key does not have the `im` scope | | 403 | `WRITE_BLOCKED_READONLY_KEY` | The key is read-only: opening the discussion can create a chat and make you a participant — see [access rights](/docs/access-rights). No request is sent to Bitrix24 | | 401 | `TOKEN_MISSING` | The API key has no Bitrix24 tokens configured | The full list of common API errors — [Errors](/docs/errors). ## Known specifics **Opening changes data.** Bitrix24 can create the comment chat and add you as a participant. That is why a read-only key gets `403 WRITE_BLOCKED_READONLY_KEY`, although the response is the same as for loading a chat. **The request is not retried automatically.** On a network failure or a `5xx` response the platform does not send the call again. Whether to retry is up to you. **Works for a forwarded post too.** A forwarded post has no comment chat; this request creates it. To find the chat without opening it, use the [comment summary](/docs/chats/messages/comments): a post without a chat does not appear there. ## See also - [Comment summary for posts](/docs/chats/messages/comments) - [Load a chat](/docs/chats/messages/load) - [Follow the comments of a post](/docs/chats/messages/comments-subscription-create) - [Mark all channel comments as read](/docs/chats/messages/comments-read-all)