The Slack CLI is Slack's official command-line development tool for creating, running, and managing Slack app projects. It supports the standard local development workflow used in Slack's current quickstarts, including creating a project from a template, authenticating with a development workspace, running the app locally, and opening app configuration. The command-line workflow is integrated with supported Slack SDKs and Bolt starter projects, so developers can move from scaffolding to testing without manually assembling the entire project structure. The alternatives listed are not Slack's official app-development command-line tool: there is no standard npm create-slack or pip slack-init workflow, and Bolt Studio is not the CLI product. Therefore, A correctly identifies Slack CLI as the official tool for command-line app development.