IT Tools MCP Server

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { z } from "zod"; import { CronExpressionParser } from 'cron-parser'; export function registerGenerateCrontab(server: McpServer) { server.registerTool("generate_crontab", { description: "Generate crontab expressions", inputSchema: { minute: z.string().describe("Minute (0-59, *, */n, n-m)").optional(), hour: z.string().describe("Hour (0-23, *, */n, n-m)").optional(), dayOfMonth: z.string().describe("Day of month (1-31, *, */n, n-m)").optional(), month: z.string().describe("Month (1-12, *, */n, n-m)").optional(), dayOfWeek: z.string().describe("Day of week (0-7, *, */n, n-m)").optional(), }, // VS Code compliance annotations annotations: { title: "Generate Crontab", description: "Generate crontab expressions", readOnlyHint: false } }, async ({ minute = "*", hour = "*", dayOfMonth = "*", month = "*", dayOfWeek = "*" }) => { try { const cronExpression = `${minute} ${hour} ${dayOfMonth} ${month} ${dayOfWeek}`; // Generate human readable description let description = "Runs "; // Minute description if (minute === "*") { description += "every minute"; } else if (minute.startsWith("*/")) { description += `every ${minute.slice(2)} minutes`; } else if (minute.includes("-")) { description += `at minutes ${minute}`; } else { description += `at minute ${minute}`; } // Hour description if (hour !== "*") { if (hour.startsWith("*/")) { description += ` of every ${hour.slice(2)} hours`; } else if (hour.includes("-")) { description += ` during hours ${hour}`; } else { description += ` at ${hour}:00`; } } // Day of month description if (dayOfMonth !== "*") { if (dayOfMonth.startsWith("*/")) { description += ` every ${dayOfMonth.slice(2)} days`; } else { description += ` on day ${dayOfMonth} of the month`; } } // Month description if (month !== "*") { const monthNames = ["", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"]; if (month.includes(",")) { const months = month.split(",").map(m => monthNames[parseInt(m)] || m).join(", "); description += ` in ${months}`; } else { description += ` in ${monthNames[parseInt(month)] || month}`; } } // Day of week description if (dayOfWeek !== "*") { const dayNames = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]; if (dayOfWeek.includes(",")) { const days = dayOfWeek.split(",").map(d => dayNames[parseInt(d)] || d).join(", "); description += ` on ${days}`; } else { description += ` on ${dayNames[parseInt(dayOfWeek)] || dayOfWeek}`; } } // Generate next few run times using proper cron parser const nextRuns = []; try { const interval = CronExpressionParser.parse(cronExpression); for (let i = 0; i < 5; i++) { const nextRun = interval.next(); nextRuns.push(nextRun.toDate().toISOString().replace('T', ' ').slice(0, 19)); } } catch (cronError) { // Fall back to basic time intervals if cron parsing fails const now = new Date(); for (let i = 0; i < 5; i++) { const nextRun = new Date(now.getTime() + (i + 1) * 60 * 1000); nextRuns.push(nextRun.toISOString().replace('T', ' ').slice(0, 19)); } } return { content: [ { type: "text", text: `Crontab Expression Generated: Expression: ${cronExpression} Description: ${description} Fields: ┌─────────── minute (0-59) │ ┌───────── hour (0-23) │ │ ┌─────── day of month (1-31) │ │ │ ┌───── month (1-12) │ │ │ │ ┌─── day of week (0-6, Sunday = 0) │ │ │ │ │ ${minute.padEnd(2)} ${hour.padEnd(2)} ${dayOfMonth.padEnd(2)} ${month.padEnd(2)} ${dayOfWeek} Common Examples: • 0 9 * * * - Every day at 9:00 AM • 0 9 * * 1-5 - Weekdays at 9:00 AM • 0 */6 * * * - Every 6 hours • 0 9 1 * * - First day of every month at 9:00 AM • 30 23 * * 0 - Every Sunday at 11:30 PM Special Characters: • * - Any value • , - List separator (1,3,5) • - - Range (1-5) • / - Step values (*/5) Next estimated runs (simplified): ${nextRuns.map((run, i) => `${i + 1}. ${run}`).join('\n')} Note: Use 'crontab -e' to edit your crontab file.`, }, ], }; } catch (error) { return { content: [ { type: "text", text: `Error generating crontab: ${error instanceof Error ? error.message : 'Unknown error'}`, }, ], }; } } ); }