n8n Workflow: Track Mandatory Paid Leave with Gemini, Gmail & Slack

Track Mandatory Paid Leave Risk and Notify Employees Automatically (Gemini + Gmail + Slack)

This n8n workflow automatically checks Japan’s mandatory paid-leave minimum each month, identifies employees at risk of falling short, generates Japanese reminders with Google Gemini, sends them via Gmail, and posts an HR summary to Slack—while logging every notification back to Google Sheets.

What this workflow does

• Runs monthly: scheduled for the first day of each month.
• Reads employee and leave data: loads the employee roster and paid-leave records from two tabs in your Google Sheets workbook (expected tabs: Employees and LeaveLog), then combines the data by employeeId.
• Calculates leave shortfall: for each active employee, it calculates the current leave-year grant date, deadline, days taken, and remaining shortfall against the required minimum.
• Filters who needs action: keeps only employees who still have a shortfall and whose deadline is within the configured alert window (via alertBeforeDays).
• Generates Japanese messages: uses Google Gemini to produce:
  • a short employee-friendly Japanese reminder
  • a one-line Japanese HR summary
• Notifies and logs: sends the employee reminder through Gmail, posts the HR summary to Slack, and appends a notification record to the NotificationLog tab in Google Sheets.

Use cases

• HR teams using n8n want automated, monthly reminders for employees approaching Japan mandatory paid-leave deadlines.
• SaaS operators and automation engineers need a reliable workflow with Gemini-generated Japanese copy, plus audit logging in Google Sheets.
• Companies centralizing leave tracking in Google Sheets and routing employee + HR updates via Gmail and Slack.

Technical details

• n8n nodes / tools: set, code, merge, filter, gmail, slack.
• Integrations: Google Sheets, Google Gemini (PaLM) API, Gmail, and Slack.
• Required setup: credentials for Sheets, Gemini (PaLM) API, Gmail, and Slack; spreadsheet ID; expected tabs (Employees, LeaveLog, NotificationLog); configuration for grantMethod, fixedGrantMonthDay (if used), requiredDays, alertBeforeDays, and the target Slack channel name.