Overdue Invoice Reminder

io.github.theluckystrikePublished by GitHub account theluckystrikev0.22.5Updated Oct 24, 2026

Overdue invoice chasers: reminder 1, reminder 2, the final notice, and the day's chase list.

VerifiedSTDIODesktop onlyProductivity & WorkflowFinance

Overview

AI-generated overview

Local MCP server that tracks unpaid invoices and drafts a three-stage dunning ladder (reminder 1, reminder 2, final notice) as Markdown or printable HTML.

What you can do
  • Register unpaid invoices with client, reference, amount in integer cents, currency and due date, and get escalation dates.
  • Record full or partial payments and see the outstanding balance and next letter amount.
  • Render the current stage's chase letter as Markdown or self-contained printable HTML.
  • Mark letters as sent so the ladder advances in order.
  • List overdue invoices worst first, age the register into current/30/60/90+ buckets, and get the day's chase list.
  • Inspect a single invoice's payments, letters and schedule, or delete a wrongly entered invoice.
When to use it
Useful for freelancers and small businesses that chase late-paying clients and want consistent reminder wording, a record of what was sent when, and an aging overview, without a full accounting system.
Requirements
Runs as a local process on the user's machine (desktop only), configured in Claude Desktop, Claude Code or Cursor. The README notes the npm package is not yet published, so a clone and build is currently the working path. Data is stored locally under the user's data directory. An optional Pro license key can be supplied via the MCP_LICENSE_KEY environment variable.
Before you install
The server does not send anything itself: letters are text you send, so delivery and tone are your responsibility. It writes invoice, payment and letter records to local files, and invoice_delete removes records permanently. The free tier caps concurrent chases at three; Pro is a paid one-time purchase. The README also mentions a hosted remote endpoint and a GitMCP docs URL that are separate from this local package.

Installation

In SourceWeft

  1. Open Overdue Invoice Reminder in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

Automated payment reminders for overdue invoices

[theluckystrike/mcp-dunning-letters MCP server]

In the official MCP Registry (io.github.theluckystrike/dunning-letters). Chase overdue invoices without losing the thread. Register an unpaid invoice, client, invoice reference, amount in integer cents, currency, due date, and the server runs the escalation ladder: reminder 1 (polite, due + 7 days), reminder 2 (firm, with the late fees note, due + 14), and the final notice (before-action wording, due + 21; the gaps are configurable per invoice). For each stage it generates the letter, as Markdown or as a self-contained printable HTML page. It records what you sent and when, lists everything overdue with days late and stage, ages the whole register into current/30/60/90+ buckets, and answers "what do I need to send today". Nothing is emailed or sent anywhere: this server produces the letter text, and sending it is your act.

Built by theluckystrike.

npm publish for @theluckystrike/mcp-dunning-letters is pending, so npx -y @theluckystrike/mcp-dunning-letters returns 404 today. Until then, a clone+build is the working path.

Install

Claude Desktop

macOS ~/Library/Application Support/Claude/claude_desktop_config.json, Windows %APPDATA%\Claude\claude_desktop_config.json:

json
{  "mcpServers": {    "dunning-letters": {      "command": "npx",      "args": ["-y", "@theluckystrike/mcp-dunning-letters"]    }  }}

Claude Code

sh
claude mcp add dunning-letters -- npx -y @theluckystrike/mcp-dunning-letters

Cursor

~/.cursor/mcp.json (global) or .cursor/mcp.json (project), same entry as Claude Desktop.

Tools

toolwhat it does
invoice_registerStart chasing an unpaid invoice: client, reference, amount, currency, due date. Returns DUN-YYYY-NNNN and the three escalation dates
payment_recordRecord money received, full or partial. A part payment lowers what the next letter asks for; covering the balance closes the ladder
letter_renderGenerate the chase letter for the current stage -- reminder 1, reminder 2 or the final notice -- as Markdown or self-contained printable HTML. Nothing is emailed: you send the text it produces
letter_sentRecord that a letter actually went out, with its date, so the ladder advances. Letters go out in order
overdue_listEvery unpaid invoice past its due date: days late, outstanding, letters sent, what is due next, worst first
aging_summaryThe whole register in current/1-30/31-60/61-90/91+ buckets, counts and totals in integer cents, per currency
chase_todayThe day's chase list: which invoices cross an escalation threshold today, which letter to send each, what falls due next
invoice_statusOne chased invoice in full: payments, letters, schedule, next action
invoice_deleteDelete an invoice entered wrongly. The id is not reissued
license_status / license_activateFree or Pro, and the key

Free vs Pro

FreePro
Unpaid invoices chased at once3Unlimited
All three letters, both formatsYesYes
Aging summary and the day's chase listYesYes
Late fee accrual in the lettersYesYes
Payment recording and historyYesYes

The cap is on how many chases run at once, never on the letters or the aging: three late payers taken from first reminder to final notice is a real chase list, and an invoice that gets paid frees its slot. What is metered is breadth, a fourth concurrent chase is a collections workload, not a freelancer's month.

Get Pro: https://mcp.zovo.one/buy/dunning-letters, $19 one-time for this server, or $39 for the bundle.

A measured insight

The ladder is anchored to the due date, not to the last letter, and the two drift apart exactly when chasing is going badly.

The worked chase in test/_client.mjs: USD 1,250.00 due 2026-06-01, gaps 7/14/21, so the letters fall due on 06-08, 06-15 and 06-22 whether or not anything was sent. If reminder 1 actually goes out late, say 06-20, twelve days after its date, a previous-letter-anchored ladder would push the final notice to 07-11. This one does not: 06-22 stands, because the client's obligation was fixed by the due date, not by when you got around to writing. Recording a sending moves only which stage is next; it never moves the schedule. The letters are also strictly sequential: an invoice 60 days late with nothing sent is still owed reminder 1, because a final notice that no polite letter preceded reads as a threat, not a chase.

The late fee is measured the same way, once: simple interest, pro-rata on a 30-day month, on the amount outstanding on the day the letter is written, rounded once to the minor unit. On the worked chase that is 125,000 minor units at 2% over 30 days late, 2,500 exactly, and after a 50,000 part payment it is 1,500 on the 75,000 that remains, so the final notice asks for 76,500 and no invented figure more.

Privacy

All data stays local, in ${XDG_DATA_HOME:-~/.local/share}/mcp-servers/dunning-letters/. Two files: invoices.json, counter.json. Nothing is sent anywhere, no account, no API key, no network call in this server at all, and the letters are rendered to text for you to send yourself; this server holds no mail credentials and wants none. License keys are verified offline.

Built by theluckystrike. https://github.com/theluckystrike

Frequently asked questions

Is there an MCP server for payment reminders or dunning letters?

Yes. The dunning-letters server at mcp.zovo.one automates accounts-receivable follow-up: tiered reminder sequences (friendly, firm, final), printable PDF letters, per-customer aging. Free tier, hosted remote endpoint.

How do I send payment reminders from Claude?

Connect https://mcp.zovo.one/mcp/dunning-letters and say: 'List overdue invoices and draft a firm reminder for Acme.' The letter follows the standard tier sequence and exports as PDF.

Use these docs as an MCP server

Any MCP client (Claude, Cursor, Windsurf, VS Code) can read this repository's documentation directly via GitMCP - no install:

Source: servers/dunning-letters/README.md at commit 1bd9d69

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

2
  1. v0.22.5LatestOct 14, 2026
  2. v0.21.0Sep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts