The defining trait of a library tournament is openness: schoolkids, retired amateurs and passers-by all come. Their strength varies, and that's no problem: after round one the Swiss system spreads players by strength, so a beginner won't immediately face a candidate master.
Announce the tournament in advance - on the board, on the venue's social pages, in local chats. A handy format for a mixed crowd is rapid 15+10 or blitz 10+0, 5-6 rounds on one weekend day.
A library tournament costs almost nothing: the room is yours, boards are usually around or brought by players, the bot is free. Signing up a mixed crowd is easy too - those with Telegram register themselves, and older visitors without a phone are added by the organizer as guests by name.
So everyone takes part, regardless of whether they get along with a phone - which matters especially for a library audience. Results for guests are entered by the staff member running the tournament.
A one-off tournament easily grows into a chess club at the library: agree on a day (say, every Saturday) and the regulars start coming on their own, bringing friends. Keep a season rating and post the table - it turns chance visitors into a community. Each tournament is created in the bot @vibechessbot in a minute: /create_tournament, /open_registration, /start_tournament and /finish_tournament - more in the organizer guide.
Those who use Telegram register themselves by link. Older visitors without a smartphone are added by the organizer as guests by name, and the organizer enters their results. So everyone takes part regardless of their relationship with technology.
Only in round one are pairings random. After that the Swiss system matches by score: beginners play beginners, strong play strong. That makes an open tournament comfortable for all levels.
Almost nothing: the room is yours, the bot is free, boards are usually around or brought by players. The only cost is certificates or symbolic prizes if you want them.
Yes, that's a common path. Set a regular day, keep a season rating and post the table. Regulars start coming on their own and bringing friends - a community forms around the library.
No, one staff member with the bot is enough: the software does the pairing and counting. A separate arbiter is only needed for official rating, which a club tournament doesn't require.
The bot is constantly improved based on real tournaments. If you need a feature that isn't there yet, message the developers right inside the bot with the /support command. Many features appeared exactly because organizers asked for them, and useful ideas get added quickly.
For educators - tournament at school. A regular format - club tournaments. General prep - how to organize a tournament. Full mechanics - organizer guide.