Basin is a Model Context Protocol (MCP) tool designed to integrate with AI code editors like Cursor and Windsurf, providing automated code quality and reliability testing. By invoking the 'check-generated-code' tool after each code generation step, Basin helps developers identify bugs, hallucinations, and unintended changes. The tool accepts parameters like user prompts, server URLs, endpoint information, and thread IDs to facilitate comprehensive testing and conversation tracking. It encourages small, isolated code changes and explicit declaration of authentication requirements for optimal performance and accuracy.