Attribute Macro prompt 

#[prompt]

Defines a prompt handler.

Attributes

• name - Override the prompt name (default: function name)
• description - Prompt description (default: doc comment)

Argument Defaults

Prompt handlers take a HashMap<String, String> of arguments. For feature parity with Python FastMCP, #[prompt] supports defaults via defaults(...):

#[prompt(defaults(greeting = "Hi"))]
fn greet(name: String, greeting: String) -> Vec<PromptMessage> {
    vec![PromptMessage::user(format!("{greeting} {name}"))]
}