Anti-spam libraries are used by developers to build their own anti-spam tools. They are open-source and available for free. They can be easily integrated into an application or website to help keep it clean from spammers. The anti-spam libraries are used to detect spam links. They work by checking whether a link is on a spam list or performing other checks, such as checking if the link is a shortened URL.
Invisible_captcha is a library that can be used to create a CAPTCHA using images that are impossible to read by humans but easy for computers. The code is available on GitHub, and there are several examples on the website. Friendly-challenge is another anti-spam library that does the same thing as invisible_captcha but has a few more features, such as multiple image sizes, custom background colors, and more. Discord Anti-Spam is an anti-spam bot for Discord servers that will prevent unwanted messages from being sent to your server. It works by allowing users to send a message with a link that's posted on a certain channel. If someone clicks on the link within 10 seconds, then the message will be delivered normally; otherwise, it'll be blocked by Discord Anti-Spam. There are several popular open source Anti-spam libraries available for developers