MCP Server Boilerplate

import { loggingContext } from '@/core/server'; import { promptRegistry } from '@/prompts/registry'; import { Prompt, PromptDefinition } from '@/prompts/types'; import { echoPrompt } from './echo'; export class PromptLoader { private static instance: PromptLoader | undefined; private loaded = false; public static getInstance(): PromptLoader { PromptLoader.instance ??= new PromptLoader(); return PromptLoader.instance; } public loadAllPrompts(): void { if (this.loaded) { loggingContext.log('debug', 'Prompts already loaded, skipping...'); return; } try { loggingContext.log('info', 'Loading prompts...'); // Register echo prompt this.registerPrompt(echoPrompt); this.loaded = true; loggingContext.log('info', 'Successfully loaded prompts'); } catch (error: unknown) { loggingContext.log('error', 'Failed to load prompts', { error: { message: error instanceof Error ? error.message : 'Unknown error', stack: error instanceof Error ? error.stack : undefined, }, }); } } private registerPrompt<TInput>(prompt: Prompt<TInput>): void { try { loggingContext.log( 'debug', `Registering prompt: ${prompt.definition.name}`, { data: { prompt: prompt.definition }, } ); this.validatePrompt(prompt); promptRegistry.register(prompt); loggingContext.log( 'debug', `Registered prompt: ${prompt.definition.name}`, { data: { prompt: prompt.definition }, } ); } catch (error: unknown) { loggingContext.log( 'error', `Failed to register prompt ${prompt.definition.name}`, { error: { message: error instanceof Error ? error.message : 'Unknown error', stack: error instanceof Error ? error.stack : undefined, }, } ); throw error; } } private validatePrompt<TInput>(prompt: Prompt<TInput>): void { loggingContext.log( 'debug', `Validating prompt: ${prompt.definition.name}`, { data: { prompt: prompt.definition }, } ); if (!prompt.definition.name) { loggingContext.log('error', 'Prompt name is required', { data: { prompt: prompt.definition }, }); throw new Error('Prompt name is required'); } if (!prompt.definition.description) { loggingContext.log('error', 'Prompt description is required', { data: { prompt: prompt.definition }, }); throw new Error( `Prompt ${prompt.definition.name} must have a description` ); } if (typeof prompt.process !== 'function') { loggingContext.log('error', 'Prompt must have a process function', { data: { prompt: prompt.definition }, }); throw new Error( `Prompt ${prompt.definition.name} must have a process function` ); } if (promptRegistry.has(prompt.definition.name)) { loggingContext.log('error', 'Prompt is already registered', { data: { prompt: prompt.definition }, }); throw new Error(`Prompt ${prompt.definition.name} is already registered`); } } public getPromptDefinitions(): PromptDefinition[] { return promptRegistry.list(); } public getPrompt(name: string): Prompt | undefined { return promptRegistry.get(name); } public isLoaded(): boolean { return this.loaded; } public reset(): void { this.loaded = false; } } // Export singleton instance export const promptLoader = PromptLoader.getInstance();