For AI agents: markdown of this page — /docs-content-en/chats/members/membership.md documentation index — /llms.txt

Membership check

GET /v1/chats/:dialogId/users/membership

Checks which of the listed users are members of the chat. One request checks up to 50 users at once, for example before inviting users to the chat or mentioning them.

Parameters

Parameter Type Required Default Description
ParameterdialogId (path) Typestring Requiredyes Default— DescriptionDialog ID: chatXXX for a group chat, a user ID for a direct dialog, or the me alias. chatXXX is the id field of a recent dialogs row, a user ID comes from the user list
ParameteruserIds (query) Typestring Requiredyes Default— DescriptionFrom 1 to 50 user IDs from the user list separated by commas, for example 7,12. Each ID is a positive integer without spaces or leading zeros. A repeated ID is allowed and counts toward the limit of 50

Any other parameter or a repeated parameter is rejected with 400 INVALID_PARAMS.

Examples

curl — personal key

Terminal 
curl "https://vibecode.bitrix24.com/v1/chats/chat123/users/membership?userIds=7,12" \
  -H "X-Api-Key: YOUR_API_KEY"

curl — OAuth application

Terminal 
curl "https://vibecode.bitrix24.com/v1/chats/chat123/users/membership?userIds=7,12" \
  -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/chat123/users/membership?userIds=7,12', {
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Not in the chat:', data.usersNotInChat)

JavaScript — OAuth application

javascript 
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/chat123/users/membership?userIds=7,12', {
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()

Response fields

Field Type Description
Fieldsuccess Typeboolean DescriptionAlways true on success
Fielddata.usersInChat Typearray DescriptionIDs of the requested users who are chat members
Fielddata.usersNotInChat Typearray DescriptionIDs of the requested users who are not chat members
Fielddata.users Typearray DescriptionBrief profiles of all requested users
Fielddata.users[].id Typenumber DescriptionUser ID
Fielddata.users[].name Typestring DescriptionFull name
Fielddata.users[].avatar Typestring DescriptionAvatar URL. An empty string when no avatar is set
Fielddata.users[].color Typestring DescriptionAvatar color in hexadecimal format
Fielddata.users[].type Typestring DescriptionUser type: user, extranet, bot and others

Response example

JSON 
{
  "success": true,
  "data": {
    "usersInChat": [7],
    "usersNotInChat": [12],
    "users": [
      { "id": 7, "name": "John Brown", "avatar": "", "color": "#df532d", "type": "user" },
      { "id": 12, "name": "Anna Smith", "avatar": "", "color": "#1eb4aa", "type": "extranet" }
    ]
  }
}

Error response example

400 — userIds was not sent:

JSON 
{
  "success": false,
  "error": {
    "code": "INVALID_PARAMS",
    "message": "`userIds` is required: 1-50 Bitrix24 user ids separated by commas (4,7), each a positive integer without spaces or leading zeros."
  }
}

Errors

HTTP Code Description
HTTP400 CodeINVALID_PARAMS DescriptionuserIds was not sent, more than 50 IDs were sent, or an ID is not a positive integer. The request has a parameter other than userIds or a repeated parameter. Checked before any call to Bitrix24
HTTP403 CodeSCOPE_DENIED DescriptionThe API key does not have the im scope
HTTP403 CodeWRITE_BLOCKED_READONLY_KEY DescriptionRead-only key, and the chat is not confirmed: a value other than chatN was passed and the personal dialog was not found in the same employee's recent dialog list — up to 20 pages and 4000 rows — or the alias creates a dialog. Rejected before any call to Bitrix24
HTTP403 CodeWRITE_BLOCKED_READONLY_KEY DescriptionRead-only key that is not an employee's personal key: an application key with a user session, a management key, or a key with an unconfirmed owner
HTTP401 CodeTOKEN_MISSING DescriptionThe API key has no Bitrix24 tokens configured
HTTP404 CodeENTITY_NOT_FOUND DescriptionBitrix24 answered "not found". The Bitrix24 code is in error.b24Code
HTTP422 CodeBITRIX_ERROR DescriptionBitrix24 returned an error. The Bitrix24 code is in error.b24Code. For a chat that does not exist, the code is CHAT_NOT_FOUND
HTTP502 CodeME_ALIAS_RESOLUTION_FAILED DescriptionFailed to resolve the user when using the me alias
HTTP502 CodeBITRIX_UNAVAILABLE DescriptionBitrix24 is unavailable or returned a server error

Full list of common API errors — Errors.

Known specifics

The call may make you a member. If the chat allows auto-join, the call adds the current user as a member, as when opening a chat. A READONLY key may make this call under two conditions: it is an employee's personal key, and the chat is confirmed — chatN was passed or the direct dialog was found in the same employee's recent dialogs. The read itself does not mark messages as read. The im scope and the user's Bitrix24 access still apply.

See also