LAML MCP Server

import {CallToolRequest, CallToolResult} from '@modelcontextprotocol/sdk/types.js'; import {McpSession} from 'flowmcp'; import {readFile, writeFile} from 'fs/promises'; import {isAbsolute, resolve} from 'path'; import { parseLaml } from '../../lamlParser/lamlParser.js'; import { validateLaml } from '../../lamlParser/lamlValidator.js'; import { extractYamlFromMarkdown } from '../../lamlParser/validators/utils/markdownUtils.js'; export interface LoadLamlArgs { project: string; path: string; } export interface LoadLamlResult { prompt?: string, content?: string; autoFixedIssues?: string[]; isValid?: boolean; } export async function handleLoadLaml( session: McpSession, request: CallToolRequest ): Promise<CallToolResult> { const args = request.params.arguments as unknown as LoadLamlArgs; const {path} = args; try { // Validate that path is absolute if (!isAbsolute(path)) { session.logger.addError({ code: 'LAML_INVALID_PATH_FORMAT', message: 'LAML file path must be absolute', context: {path} }); return session.getResult({}); } // Resolve the full path const fullPath = resolve(path); // Read the LAML file const originalContent = await readFile(fullPath, 'utf-8'); // Parse LAML content const parseResult = parseLaml(originalContent, fullPath); // Validate and auto-fix LAML const validationResult = validateLaml(parseResult, session, originalContent, fullPath); // Write fixed content back to file if there were auto-fixes if (validationResult.fixedContent && validationResult.autoFixedIssues.length > 0) { await writeFile(fullPath, validationResult.fixedContent, 'utf-8'); } // Extract YAML content from the fixed or original content const contentToExtract = validationResult.fixedContent || originalContent; const yamlExtractionResult = extractYamlFromMarkdown(contentToExtract, fullPath); const result: LoadLamlResult = { prompt: 'Provide a brief summary of errors and auto-fixes if any', isValid: validationResult.isValid, autoFixedIssues: validationResult.autoFixedIssues, content: yamlExtractionResult.yamlContent, }; return session.getResult(result); } catch (error) { let errorMessage: string; /* istanbul ignore if */ if (error instanceof Error) { errorMessage = error.message; } else { errorMessage = 'Unknown error'; } const nodeError = error as NodeJS.ErrnoException; if (nodeError.code === 'ENOENT') { session.logger.addError({ code: 'LAML_FILE_NOT_FOUND', context: {path} }); return session.getResult({}); } if (nodeError.code === 'EACCES') { session.logger.addError({ code: 'LAML_PERMISSION_DENIED', context: {path} }); return session.getResult({}); } if (nodeError.code === 'EISDIR') { session.logger.addError({ code: 'LAML_PATH_IS_DIRECTORY', context: {path} }); return session.getResult({}); } // For other critical errors that prevent normal operation session.logger.addError({ code: 'LAML_READ_CRITICAL_ERROR', context: {path, nodeErrorCode: nodeError.code, originalError: errorMessage} }); return session.getResult({}); } }