Opens a multi-person direct message or just a 1:1 direct message.

Optional Params

• channel - Resume a conversation by supplying an im or mpim's ID. Or provide the users field instead. ex: G1234567890
• return_im - Boolean, indicates you want the full IM channel definition in the response. ex: true
• users - Comma separated lists of users. If only one user is included, this creates a 1:1 DM. The ordering of the users is preserved whenever a multi-person direct message is returned. Supply a channel when not supplying users. ex: W1234567890,U2345678901,U3456789012

Errors the API can return:

• channel_not_found - Value passed for channel was invalid
• method_not_supported_for_channel_type - This type of conversation cannot be used with this method.
• not_enough_users - Needs at least 2 users to open
• too_many_users - Needs at most 8 users to open
• user_disabled - A specified user has been disabled
• user_not_found - Value(s) passed for users was invalid
• user_not_visible - The calling user is restricted from seeing the requested user.
• users_list_not_supplied - Missing users in request