You're seeing just the function set_purpose, go back to SlackWeb.Conversations module for more information.
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set_purpose(channel, purpose, optional_params \\ %{})

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Change the purpose of a conversation. The calling user must be a member of the conversation. Not all conversation types may have a purpose set.

Required Params

  • channel - Conversation to set the purpose of. ex: G1234567890
  • purpose - A new, specialer purpose ex: My More Special Purpose

Errors the API can return:

  • channel_not_found - Value passed for channel was invalid
  • is_archived - Channel has been archived
  • method_not_supported_for_channel_type - This type of conversation cannot be used with this method.
  • not_in_channel - Authenticated user is not in the channel.
  • too_long - Purpose was longer than 250 characters.
  • user_is_restricted - This method cannot be called by a restricted user or single channel guest.