Bitrix24 Chats API

openapi: 3.0.3
info:
  title: Bitrix24 REST BIconnector Chats API
  version: 1.0.0
  description: 'Bitrix24 REST API provides access to CRM, tasks, drive, chats, telephony, e-commerce, automation, and other modules. Documentation: https://apidocs.bitrix24.com'
  contact:
    name: Bitrix24 Developer Support
    url: https://apidocs.bitrix24.com/support.html
  license:
    name: MIT
    url: https://github.com/bitrix-tools/b24-rest-docs/blob/main/LICENSE
  x-logo:
    url: https://apidocs.bitrix24.com/_images/bitrix24logo.svg
servers:
- url: https://{portal}.bitrix24.com/rest
  description: Your Bitrix24 portal (cloud)
  variables:
    portal:
      default: your-portal
      description: Subdomain of your Bitrix24 portal
- url: https://{host}/rest
  description: On-Premise Bitrix24 installation
  variables:
    host:
      default: your-bitrix24.example.com
      description: Host of your on-premise installation
security:
- AccessToken: []
tags:
- name: Chats
paths:
  /im.chat.add:
    post:
      summary: Create Chat im.chat.add
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.add` creates a new chat.
      operationId: im_chat_add
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/im-chat-add.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                USERS:
                  type: array
                  items: {}
                  description: '| An array of user IDs to be added to the chat.'
                TYPE:
                  type: string
                  description: '| Type of chat:'
                TITLE:
                  type: string
                  description: '| Title of the chat.'
                DESCRIPTION:
                  type: string
                  description: '| Description of the chat ||'
                COLOR:
                  type: string
                  description: '| Color of the chat. Possible values:'
                MESSAGE:
                  type: string
                  description: '| The first message in the chat ||'
                AVATAR:
                  type: string
                  description: '| Avatar of the chat in base64 string format.'
                ENTITY_TYPE:
                  type: string
                  description: '| Type of object to link the chat with external context.'
                ENTITY_ID:
                  type: string
                  description: '| Identifier of the object within `ENTITY_TYPE`.'
                COPILOT_MAIN_ROLE:
                  type: string
                  description: '| Code of the main role for BitrixGPT.'
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                USERS:
                  type: array
                  items: {}
                  description: '| An array of user IDs to be added to the chat.'
                TYPE:
                  type: string
                  description: '| Type of chat:'
                TITLE:
                  type: string
                  description: '| Title of the chat.'
                DESCRIPTION:
                  type: string
                  description: '| Description of the chat ||'
                COLOR:
                  type: string
                  description: '| Color of the chat. Possible values:'
                MESSAGE:
                  type: string
                  description: '| The first message in the chat ||'
                AVATAR:
                  type: string
                  description: '| Avatar of the chat in base64 string format.'
                ENTITY_TYPE:
                  type: string
                  description: '| Type of object to link the chat with external context.'
                ENTITY_ID:
                  type: string
                  description: '| Identifier of the object within `ENTITY_TYPE`.'
                COPILOT_MAIN_ROLE:
                  type: string
                  description: '| Code of the main role for BitrixGPT.'
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.get:
    post:
      summary: Get Chat ID im.chat.get
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.get` retrieves the chat ID.
      operationId: im_chat_get
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/im-chat-get.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                ENTITY_TYPE:
                  type: string
                  description: '| The type of object for linking the chat to an external context. Passed as a string.'
                ENTITY_ID:
                  type: string
                  description: '| Identifier of the object within `ENTITY_TYPE`.'
              required:
              - ENTITY_TYPE
              - ENTITY_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                ENTITY_TYPE:
                  type: string
                  description: '| The type of object for linking the chat to an external context. Passed as a string.'
                ENTITY_ID:
                  type: string
                  description: '| Identifier of the object within `ENTITY_TYPE`.'
              required:
              - ENTITY_TYPE
              - ENTITY_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.leave:
    post:
      summary: Leave Chat im.chat.leave
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.leave` removes the current user from the chat.
      operationId: im_chat_leave
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-users/im-chat-leave.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
              required:
              - CHAT_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
              required:
              - CHAT_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.mute:
    post:
      summary: Disable Notifications from Chat im.chat.mute
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.mute` disables or enables notifications in the specified chat.
      operationId: im_chat_mute
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/special-operations/im-chat-mute.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| The identifier of the chat. You can obtain the identifier using the im.chat.get method ||'
                DIALOG_ID:
                  type: string
                  description: '| The chat identifier in the format:'
                MUTE:
                  type: string
                  description: '| Notification control:'
              required:
              - CHAT_ID
              - DIALOG_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| The identifier of the chat. You can obtain the identifier using the im.chat.get method ||'
                DIALOG_ID:
                  type: string
                  description: '| The chat identifier in the format:'
                MUTE:
                  type: string
                  description: '| Notification control:'
              required:
              - CHAT_ID
              - DIALOG_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.setOwner:
    post:
      summary: Change Chat Owner im.chat.setOwner
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.setOwner` changes the owner of the chat.
      operationId: im_chat_setOwner
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-update/im-chat-set-owner.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USER_ID:
                  type: integer
                  description: '| Identifier of the new chat owner.'
              required:
              - CHAT_ID
              - USER_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USER_ID:
                  type: integer
                  description: '| Identifier of the new chat owner.'
              required:
              - CHAT_ID
              - USER_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.updateAvatar:
    post:
      summary: Update Chat Avatar im.chat.updateAvatar
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.updateAvatar` updates the chat avatar.
      operationId: im_chat_updateAvatar
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-update/im-chat-update-avatar.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                AVATAR:
                  type: string
                  description: '| Image in Base64 format.'
              required:
              - CHAT_ID
              - AVATAR
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                AVATAR:
                  type: string
                  description: '| Image in Base64 format.'
              required:
              - CHAT_ID
              - AVATAR
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.updateColor:
    post:
      summary: Change Chat Color im.chat.updateColor
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.updateColor` updates the chat color for the mobile application.
      operationId: im_chat_updateColor
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-update/im-chat-update-color.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                COLOR:
                  type: string
                  description: '| Chat color for the mobile application. Possible values:'
              required:
              - CHAT_ID
              - COLOR
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                COLOR:
                  type: string
                  description: '| Chat color for the mobile application. Possible values:'
              required:
              - CHAT_ID
              - COLOR
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.updateTitle:
    post:
      summary: Update Chat Title im.chat.updateTitle
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.updateTitle` updates the chat title.
      operationId: im_chat_updateTitle
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-update/im-chat-update-title.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Chat identifier.'
                TITLE:
                  type: string
                  description: '| Chat title.'
              required:
              - CHAT_ID
              - TITLE
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Chat identifier.'
                TITLE:
                  type: string
                  description: '| Chat title.'
              required:
              - CHAT_ID
              - TITLE
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.user.add:
    post:
      summary: Invite Participants to Chat im.chat.user.add
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.user.add` adds users to a chat.
      operationId: im_chat_user_add
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-users/im-chat-user-add.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USERS:
                  type: array
                  items: {}
                  description: '| Array of user identifiers to be added to the chat.'
                HIDE_HISTORY:
                  type: string
                  description: '| Hide chat history for added users:'
              required:
              - CHAT_ID
              - USERS
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USERS:
                  type: array
                  items: {}
                  description: '| Array of user identifiers to be added to the chat.'
                HIDE_HISTORY:
                  type: string
                  description: '| Hide chat history for added users:'
              required:
              - CHAT_ID
              - USERS
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.user.delete:
    post:
      summary: Exclude Participants from Chat im.chat.user.delete
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.user.delete` removes a user from the chat.
      operationId: im_chat_user_delete
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-users/im-chat-user-delete.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USER_ID:
                  type: integer
                  description: '| Identifier of the user to be excluded from the chat.'
              required:
              - CHAT_ID
              - USER_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
                USER_ID:
                  type: integer
                  description: '| Identifier of the user to be excluded from the chat.'
              required:
              - CHAT_ID
              - USER_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.chat.user.list:
    post:
      summary: Get Chat Participant IDs im.chat.user.list
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.chat.user.list` returns a list of chat participant IDs.
      operationId: im_chat_user_list
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/chat-users/im-chat-user-list.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
              required:
              - CHAT_ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                CHAT_ID:
                  type: integer
                  description: '| Identifier of the chat.'
              required:
              - CHAT_ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.counters.get:
    post:
      summary: Get Counters im.counters.get
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.counters.get` retrieves the counters for unread messages and notifications for the current user.
      operationId: im_counters_get
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/im-counters-get.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
          application/x-www-form-urlencoded:
            schema:
              type: object
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.department.colleagues.list:
    post:
      summary: Get the List of Colleagues for the Current User im.department.colleagues.list
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.department.colleagues.list` retrieves the list of colleagues for the current user. For a manager, the method will return a list of subordinates and all supervisors.
      operationId: im_department_colleagues_list
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/departments/im-department-colleagues-list.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                USER_DATA:
                  type: string
                  description: '| Return detailed user data.'
                OFFSET:
                  type: integer
                  description: '| Offset for user selection ||'
                LIMIT:
                  type: integer
                  description: '| Number of items in the selection. Default is `10`. Maximum value is `50` ||'
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                USER_DATA:
                  type: string
                  description: '| Return detailed user data.'
                OFFSET:
                  type: integer
                  description: '| Offset for user selection ||'
                LIMIT:
                  type: integer
                  description: '| Number of items in the selection. Default is `10`. Maximum value is `50` ||'
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.department.employees.get:
    post:
      summary: Get a List of Employees from Departments im.department.employees.get
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.department.employees.get` retrieves a list of employees from the specified departments.
      operationId: im_department_employees_get
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/departments/im-department-employees-get.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                ID:
                  type: array
                  items: {}
                  description: '| An array of department IDs. You can pass a string with a JSON array of IDs.'
                USER_DATA:
                  type: string
                  description: '| Return detailed user data.'
              required:
              - ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                ID:
                  type: array
                  items: {}
                  description: '| An array of department IDs. You can pass a string with a JSON array of IDs.'
                USER_DATA:
                  type: string
                  description: '| Return detailed user data.'
              required:
              - ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.department.get:
    post:
      summary: Get Information About the Department im.department.get
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the [MCP server](../../../ai-tools/mcp.md) so that the assistant can utilize the official REST documentation. The method `im.department.get` retrieves data about departments by their `ID` identifiers.
      operationId: im_department_get
      tags:
      - Chats
      externalDocs:
        url: https://apidocs.bitrix24.com/api-reference/chats/departments/im-department-get.html
        description: Official Documentation
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                ID:
                  type: array
                  items: {}
                  description: '| An array of department identifiers. You can pass a string with a JSON array of identifiers.'
                USER_DATA:
                  type: string
                  description: '| Return data about the department head.'
              required:
              - ID
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                ID:
                  type: array
                  items: {}
                  description: '| An array of department identifiers. You can pass a string with a JSON array of identifiers.'
                USER_DATA:
                  type: string
                  description: '| Return data about the department head.'
              required:
              - ID
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixResponse'
        4XX:
          description: Request error (400, 401, 403)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BitrixError'
      security:
      - AccessToken: []
      - OAuth2:
        - im
  /im.department.managers.get:
    post:
      summary: Get a List of Department Managers im.department.managers.get
      description: If you are developing integrations for Bitrix24 using AI tools (Codex, Claude 

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# Full source: https://raw.githubusercontent.com/api-evangelist/bitrix24/refs/heads/main/openapi/bitrix24-chats-api-openapi.yml