MCP Elicitations Demo Server

import { Server } from "@modelcontextprotocol/sdk/server/index.js"; import { CreateMessageRequest, CreateMessageResultSchema, } from "@modelcontextprotocol/sdk/types.js"; // Message content types based on MCP specification export interface TextContent { [x: string]: unknown; type: "text"; text: string; } export interface ImageContent { [x: string]: unknown; type: "image"; data: string; // base64-encoded image data mimeType: string; } export interface AudioContent { [x: string]: unknown; type: "audio"; data: string; // base64-encoded audio data mimeType: string; } export type MessageContent = TextContent | ImageContent | AudioContent; export interface Message { [x: string]: unknown; role: "user" | "assistant"; content: MessageContent; } export interface ModelHint { [x: string]: unknown; name?: string; } export interface ModelPreferences { [x: string]: unknown; hints?: ModelHint[]; costPriority?: number; // 0-1, higher values prefer cheaper models speedPriority?: number; // 0-1, higher values prefer faster models intelligencePriority?: number; // 0-1, higher values prefer more capable models } export interface SamplingOptions { messages: Message[]; modelPreferences?: ModelPreferences; systemPrompt?: string; maxTokens?: number; } // Enhanced sampling helper with full specification support export const requestSampling = async ( options: SamplingOptions, server: Server ) => { const request: CreateMessageRequest = { method: "sampling/createMessage", params: { messages: options.messages, modelPreferences: options.modelPreferences, systemPrompt: options.systemPrompt, maxTokens: options.maxTokens ?? 100, }, }; return await server.request(request, CreateMessageResultSchema); }; // Backward compatibility helper for simple text sampling export const requestTextSampling = async ( text: string, systemPrompt: string = "You are a helpful assistant.", maxTokens: number = 100, server: Server, modelPreferences?: ModelPreferences ) => { return await requestSampling( { messages: [ { role: "user", content: { type: "text", text, }, }, ], systemPrompt, maxTokens, modelPreferences, }, server ); };