prompt

adjective:done without delay; immediate
- We appreciate your prompt response to our inquiry.
verb:to cause or urge someone to do something
- The threat prompted increase in security budget.
noun:a cue or a word given to an actor or speaker to begin their speech or performance
- The actor waited nervously in the wings for his prompt.
noun:a symbol or message on a computer screen requesting user input
- Type your password at the command prompt.
noun:an instruction given to a computer or other system
- AI relies on prompts to generate responses and provide information to users.