You're seeing just the function set_topic, go back to Slack.Web.Groups module for more information.
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set_topic(channel, topic, optional_params \\ %{})

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Sets the topic for a private channel.

Required Params

  • channel - Private channel to set the topic of
  • topic - The new topic ex: My Topic

Errors the API can return:

  • channel_not_found - Value passed for channel was invalid.
  • is_archived - Private group has been archived
  • too_long - Topic was longer than 250 characters.
  • user_is_restricted - Setting the topic is a restricted action.