Pkgbot is a command-line tool that was initially developed by Karen Yavine and Alon Niv for the Snyk Security Team to help research vulnerabilities in package repositories. Pkgbot uses APIs such as npm and RubyGems to collect information about packages, including their downloads and vulnerabilities. The tool has since been open-sourced and is now available for anyone to use and contribute to. With its ability to provide detailed information about packages, Pkgbot aims to make vulnerability research more efficient and accessible.