UserPromptSubmit

The UserPromptSubmit hook is an interception mechanism that fires the moment you press Enter on a prompt, but before the text is actually sent to the Claude model. It is the most powerful tool for prompt engineering automation, allowing you to programmatically rewrite, validate, or enhance your instructions on the fly.

Visit the following resources to learn more:

• @official@Hooks reference
• @official@Automate workflows with hooks
• @article@Rewrite Prompts on the Fly with UserPromptSubmit Hooks