Himalaya is a command line interface (CLI) tool designed for managing emails through automation and integration with terminal user interfaces (TUIs). Users appreciate its ease of use for creating custom email workflows, as well as its compatibility with other projects like August for rendering HTML to text. The tool supports features like OAuth2 and JSON output, and there are discussions around its ability to refresh emails, re-write headers, and manage filters programmatically. Users have also expressed a desire for better documentation and examples to explore its capabilities further. The ongoing interest in TUIs reflects a broader trend towards simplifying complex workflows and improving user experience in email management.