Creating flexible command-line applications in Go is streamlined by building an abstraction for handling subcommands using a tree data structure, where each node represents a command with optional subcommands. This approach simplifies the process of organizing commands like "add" and "subtract" under a root command, and supports features such as nested subcommands, argument parsing, and context-aware help messages. By structuring each command with properties for its name, usage, execution logic, and associated subcommands, developers can easily extend functionality and automatically generate helpful usage outputs for users. Compared to using repetitive switch statements, this method enhances maintainability and extensibility, allowing for seamless integration of features such as nested commands and custom help text. As a next step, implementing a flag system per command—ideally through a dedicated struct for flag management—enables robust, user-friendly interfaces similar to those in established Go CLI frameworks.