Cron to Natural Language (and Back): Stop Guessing Your Schedules

The cron blind spot\n\nEvery senior engineer I know still double-checks cron expressions against crontab.guru. The 5-field format is terse, and one wrong character changes *every other Monday* to *every day in every other month*.\n\n## The API\n\nCron Parser API — parse, explain, validate, generate next N runs, and translate between natural language and cron notation:\n\n``bash\n# Explain an expression\ncurl 'https://api.lazy-mac.com/cron-parser/api/v1/explain?expr=0+9+*+*+1-5'\n# → 'At 9:00 AM on weekdays'\n\n# Natural language → cron\ncurl -X POST https://api.lazy-mac.com/cron-parser/api/v1/from-text -d '{\"text\":\"every 15 minutes during business hours\"}'\n# → '*/15 9-18 * * 1-5'\n\n# Next 5 runs in Asia/Seoul\ncurl 'https://api.lazy-mac.com/cron-parser/api/v1/next?expr=0+9+*+*+1-5&tz=Asia/Seoul&count=5'\n# → ['2026-04-14T09:00:00+09:00', ...]\n\n# Validate\ncurl 'https://api.lazy-mac.com/cron-parser/api/v1/validate?expr=0+9+*+*+1-5'\n# → { valid: true }\n`\n\nSupports both 5-field (standard cron) and 6-field (with seconds, for Quartz-style schedulers).\n\nFree 100/day. Pro $9.99/mo unlimited.\n\n## Why natural-language matters for AI agents\n\nWith the MCP server, Claude can write scheduled jobs for you:\n\n`bash\nnpx -y @lazymac/mcp\n> Set up a cron to run ./backup.sh every 6 hours\n# → '0 */6 * * *'\n> What time will this next fire if I'm in Seoul?\n``\n\nSaves you from having to mentally parse an expression every time you edit a schedule.\n\n## Companion APIs\n\n- Timezone API — convert between timezones, list observing DST, meeting planner\n- Webhook Inspector — capture + replay webhooks triggered by your crons\n- AI Spend Tracker — schedule daily AI cost reports\n\nAll bundled in MCP Pro $29/mo.

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