1. get_stories
Fetching stories from different categories including top stories, new stories, Ask HN posts, and Show HN posts.
2. get_story_info
Fetching detailed information and comments associated with a specific story.
3. search_stories
Searching for stories on Hacker News using query keywords.
4. get_user_info
Fetching user information and activity summary for a specific Hacker News user.