Developed and standardized multi-file attachment support for task messages in the CLI tools of both the a2aproject/a2a-samples and google/A2A repositories. The work focused on enhancing usability and consistency by implementing a loop-based input system in Python, allowing users to attach multiple files per message. Robust error handling was integrated to manage missing files and read errors, improving reliability during file handling operations. By achieving feature parity across repositories, the changes streamlined collaboration and reduced friction for users needing to include supporting documents. The engineering approach emphasized maintainable CLI development, careful error management, and cross-repository consistency in user experience.