registerPrompt

Ship a reusable prompt users can invoke

registerPrompt adds a prompt to your server: a named, parameterized message template the user picks from the host’s prompt menu. The handler returns the messages the host inserts into the conversation.

Example

A prompt that takes one argument and returns a single user message.

server.ts

import { McpServer } from "skybridge/server";
import { z } from "zod";

const server = new McpServer({ name: "travel", version: "1.0" }).registerPrompt(
  {
    name: "trip-summary",
    title: "Trip summary",
    description: "Summarize a trip to a destination.",
    argsSchema: { destination: z.string() },
  },
  ({ destination }) => ({
    messages: [
      {
        role: "user",
        content: { type: "text", text: `Summarize a trip to ${destination}.` },
      },
    ],
  }),
);

Signature

server.registerPrompt(config: PromptConfig, handler: PromptHandler): McpServer;

The config-object form returns the server, so it chains alongside registerTool and registerResource.

Config

type PromptConfig = {
  name: string;
  title?: string;
  description?: string;
  argsSchema?: ZodRawShape; // Zod shape; validates args and types the handler
};

name, title, description

name identifies the prompt; title and description are what the host shows in its prompt menu.

argsSchema

A Zod raw shape whose fields become the prompt’s arguments. It validates what the host passes and types the handler’s input. Wrap a field in completable() to autocomplete it as the user types, see Completions.

Handler

Receives the validated arguments and returns the messages to insert.

type PromptHandler = (
  args: Args,
  extra: RequestHandlerExtra,
) => Promise<{
  description?: string;
  messages: Array<{
    role: "user" | "assistant";
    content: ContentBlock;
  }>;
}>;

Each message’s content is a standard MCP ContentBlock, most often { type: "text", text }.

Register Prompts

The guide, with completions

registerResource

Expose readable content

McpServer

The server you register on