Group Defender: a shield for your chat

Sooner or later a big group chat gets someone who posts a suspicious link, a file of unknown origin or an explicit picture. Moderators are not always online, and damage happens within seconds. Group Defender takes over part of that checking.

It is a small utility for groups. According to its profile, it scans files and links for viruses and malware and checks photos and animations for NSFW content, meaning material for adults.

What the bot checks

There are two main jobs, both about the safety of members.

• Links and files: a search for signs of viruses and malicious software.
• Photos and animations: detecting explicit content so it does not show up in the shared chat.

Image checking is especially handy in public communities where anyone can post anything. The project is open source, so you can study how it works yourself.

Getting started

Start the bot and send /help, and it explains how to use it. Then add it to your group so it can watch the chat content.

To read messages and react to them, the bot needs the relevant admin rights. Grant exactly what is required and no more.

Three commands and almost no setup

The command set is minimal: /help for instructions, /feedback to send a note to the author and /donate for voluntary support. There are no heavy menus or dozens of toggles.

If something misbehaves, write through /feedback. For a small utility, that channel solves a lot.

Why automatic scanning does not replace attention

Any scanner catches only known threats. Brand new malicious files and fresh phishing links can slip through, and picture filters sometimes err in both directions.

So think of the bot as a first line of defense rather than the only one. Admins should keep their own chat rules and review suspicious cases.

• Do not open files from a chat if you are unsure about the sender.
• Do not follow links that ask for a password or a code from a message.
• Do not install programs from files sent to you.

If your group has several admins, agree in advance who reacts when the bot flags something. That way a suspicious file never sits unattended, and members quickly see that the chat has clear rules.

Who benefits most

The bot suits admins of open communities, interest chats and study groups. Those places have many strangers, and checking the whole stream by hand eats time.

Parents and teachers may find it useful in school chats too, where unwanted images appear without warning.

Privacy and support

The bot checks what lands in the group, so tell members that content is analyzed automatically. It is fairer and answers questions in advance.

The project grows through the author's efforts and runs on voluntary donations via /donate. News and updates appear on the developer's official channel, linked from the bot profile.

Paying for basic protection is not required: a donation remains a personal decision for each admin.