Invoice Reminder AI Agent

What this agent does

Chasing late payments is a task freelancers and small businesses both hate and both delay, which is exactly why invoices stay unpaid longer than they should. This agent watches your invoice tracker and sends the right reminder at the right time — friendly at first, firmer as it ages — so payment follow-up never depends on you remembering.

1. stage-1-due-check — reads your invoice source (a Google Sheet or Notion database with due dates and paid/unpaid status) and identifies every invoice that's due soon, due today, or overdue.
2. stage-2-tone-draft — for each invoice needing a nudge, drafts an email using the appropriate tone tier (a friendly heads-up before the due date, a direct reminder just after, a firmer follow-up for anything 14+ days overdue) and saves it as a draft for your review — nothing sends without your sign-off.

Every run logs which invoices were checked and which reminders were drafted, so you always know what's pending in your outbox.

Requirements

• An invoice tracker in Google Sheets or Notion with at minimum: client name, email, amount, due date, and paid/unpaid status.
• Gmail or Outlook access for drafting (never auto-sending).
• Works on OpenClaw (scheduled trigger + Sheets/Notion + email plugin).

Setup

1. Unzip the package into your workspace, keeping the folder structure intact.
2. Point the tracker configuration at your Sheet ID or Notion database ID and map the column/property names.
3. Adjust the wording for each tone tier and the day thresholds that trigger them.
4. Run the starter prompt against your current tracker to see what it would draft today.
5. Schedule it to run daily.

What you get

• Every invoice automatically checked against due dates and payment status on your schedule
• A tone-appropriate reminder draft for each invoice that needs one — friendly, direct, or firm depending on how overdue it is
• Nothing ever sends without your sign-off — every reminder is a draft for review
• A log of exactly which invoices were checked and which reminders were drafted, so you always know what's pending