Home · Setup · Claude.ai and Claude Desktop connectors
Chase overdue invoices on a ladder anchored to the due date: reminder 1, reminder 2, the final notice, with the aging and the day's chase list. You register an unpaid invoice, client, reference, amount in whole minor units, currency, due date, and it returns a DUN-YYYY-NNNN id with the three escalation dates: reminder 1 at due plus 7 days, reminder 2 at due plus 14, the final notice at due plus 21, configurable per invoice. The ladder is anchored to the due date, not to the last letter, so a reminder that goes out twelve days late does not push the final notice back: the client's obligation was fixed by the due date. Letters go out strictly in order, and the late fee is simple interest, pro-rata on a 30-day month, on what is outstanding the day the letter is written, rounded once to the minor unit. letter_render produces the letter as Markdown or a self-contained printable HTML page, letter_sent records that it actually went out, and payment_record lowers what the next letter asks for, with a payment that covers the balance closing the ladder. Nothing is emailed or sent anywhere: the server produces the letter text, and sending it is your act.
The register lives in the hosted store behind the token, so the three free concurrent chases and the DUN-YYYY-NNNN numbers follow the key rather than the machine, and the sender block on the letters comes from the shared business profile behind that same token. There is no network call inside the server on any route, so the ladder dates, the late fee and the aging are the same here as on a laptop, down to the minor unit. letter_render returns the letter inline and nothing is emailed on any route: the server produces the text and the sending is yours.
| You say | Tool |
|---|---|
| Register INV-1042 to Acme Ltd, USD 1,250.00, due 2026-06-01, late fees at 2% a month. | invoice_register |
| What do I need to send today? | chase_today |
| They paid 500 on the 20th; record it and show me the final notice when it falls due. | payment_record then letter_render |
On the worked chase, USD 125,000 minor units due 2026-06-01 with the default gaps falls due on 06-08, 06-15 and 06-22 whether or not anything was sent, and on 2026-07-01 the fee at 2% per month is exactly 2,500. After a 50,000 part payment the fee on the remainder is 1,500, so the final notice asks for 76,500 and no invented figure more. The unit suite recomputes every one of those by hand.
https://mcp.zovo.one/mcp/connect mints an anonymous token and prints a URL per server, including this one, shaped like https://mcp.zovo.one/mcp/dunning-letters/t/<token>. That URL works with no headers: the token is in the path, not in an Authorization field this form does not have.
Idle anonymous tokens are swept after 30 days. Since this route has no filesystem, a file MCP Dunning Letters generates comes back as a download link that expires after one hour. A Pro key can replace the token in the same URL and removes the free-tier limits.
On an individual Pro or Max plan you add the connector yourself from Customize, Connectors. On Team and Enterprise it is the other way round: only an Owner or Primary Owner can add a custom connector, at Organization settings, Connectors, and members then connect to what the Owner added rather than pasting their own URL.
Free: Three unpaid invoices chased at once, with all three letters in both formats, the aging summary, the day's chase list and payment recording free on every tier. An invoice that gets paid frees its slot, because the cap is on how many chases run at once, never on the letters or the aging. Pro is $19 once, verified offline, and binds to the token after checkout.
No. Add custom connector offers an Advanced settings section with an OAuth Client ID and Client Secret, but the connect-by-URL route does not use it. Leave both blank: the token in the URL path is what authenticates.
That is documented, not a bug: on Team and Enterprise, only an Owner or Primary Owner can add a custom connector, at Organization settings, Connectors, Add, Custom, Web. After that, members connect to the URL the Owner added from Customize, Connectors.
Yes. The token segment of the URL from /mcp/connect can be replaced with a Pro key, which removes the free-tier limits on MCP Dunning Letters for that connector.
The connector runs server-side with no filesystem of its own, so any file MCP Dunning Letters produces is handed back as a download link that expires after one hour, rather than a path on disk.
MCP Dunning Letters in detail · How connect-by-URL works · Every server for Claude.ai and Claude Desktop connectors · All clients · Claude.ai and Claude Desktop connectors docs · Buy Pro