Slack Slash Commands API

Slack Slash Commands allow users to invoke app functionality directly from the message composer box by typing a forward slash followed by a command name and optional parameters. When a user triggers a slash command, Slack sends an HTTP POST request to the app's configured Request URL with details about the command, user, channel, and any text entered. The app can respond with a message (visible to everyone or only to the invoking user), open a modal, or trigger other interactive flows.