To identify one-on-one chats, you can use the chat id which is unique for each chat. However, to get more information about the chat, such as the participants, you can use the 'List Members of Chat' API. This API returns the list of all members in a chat, which can help you identify one-on-one chats.
Here's an example of how you can use this API:
GET /chats/{chat-id}/members
This will return a list of chat members, which includes the user IDs of the participants. For one-on-one chats, this list should contain two user IDs - yours and the other participant's.
Please note that you need to have the appropriate permissions to use this API. Specifically, you need one of the following permissions: Chat.ReadBasic.All, Chat.Read.All, Chat.ReadWrite.All.
Ref Doc: https://docs.microsoft.com/en-us/graph/api/chat-list-members?view=graph-rest-beta&tabs=http
Thanks,
Nivedipa
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