import { McpError, ErrorCode } from '@modelcontextprotocol/sdk/types.js';
import { IRequestStrategy } from './IRequestStrategy';
import { IRequestHandlerDependencies } from '../interfaces/IRequestHandlerServices';
import { logger } from '../../utils/logger';
interface PromptsGetRequest {
method: string;
params?: {
name: string;
arguments?: Record<string, unknown>;
};
}
interface PromptsGetResponse {
description?: string;
messages: Array<{
role: 'user' | 'assistant';
content: {
type: 'text';
text: string;
};
}>;
}
/**
* Strategy for handling prompts get requests
* Follows Strategy Pattern for clean request handling
*/
export class PromptsGetStrategy implements IRequestStrategy<PromptsGetRequest, PromptsGetResponse> {
constructor(
private dependencies: IRequestHandlerDependencies
) {}
canHandle(request: PromptsGetRequest): boolean {
return request.method === 'prompts/get';
}
async handle(request: PromptsGetRequest): Promise<PromptsGetResponse> {
try {
logger.systemLog('PromptsGetStrategy: Handling prompts get request');
const promptName = request.params?.name;
if (!promptName) {
throw new McpError(ErrorCode.InvalidParams, 'Prompt name is required');
}
// Get the prompt content
const promptContent = await this.dependencies.promptsListService.getPrompt(promptName);
if (!promptContent) {
throw new McpError(ErrorCode.InvalidParams, `Prompt "${promptName}" not found`);
}
// Return the prompt as a user message in MCP format
return {
messages: [
{
role: 'user',
content: {
type: 'text',
text: promptContent
}
}
]
};
} catch (error) {
if (error instanceof McpError) {
throw error;
}
logger.systemError(error as Error, 'PromptsGetStrategy');
throw new McpError(ErrorCode.InternalError, 'Failed to get prompt', error);
}
}
}
