For Claude, ChatGPT, Grok and Mistral Vibe
Your AI can send e-mails, but not letters. For everything that still needs a letter: a defect notice to your landlord, a withdrawal from a phone or doorstep contract, a letter to someone without e-mail, a complaint to a company that lists only a postal address.
Your AI writes it with you. You check the preview and the price. We print it and post it in your name, as a standard or registered letter, and e-mail you the status.
Invited? Connect your AI.
Not invited yet? Join the waitlist. We e-mail you when we open.
Opening in early November 2026. Want to try it before then? Ask for an access code: support@agentletterdesk.com
Standard letter from €2.20Registered letter from €5.90Cancel until printing
01How it works
An example of the flow from the launch. Today, letters are not mailed yet. The names and addresses are made up.
When you connect, you sign in once and enter your name. Every letter carries that name.
My old landlord in Madrid still has my €900 deposit. Please send him a demand letter by registered mail.
I can do that. I will write it in Spanish, your landlord’s language. What is his name and address? And on which date did you hand back the keys?
Javier Ortega Ruiz, Calle Ejemplo 14, 3º B, 28004 Madrid. I handed back the keys on September 1.
Agent Letter DeskRead your name and addressget_account
Agent Letter DeskPrepare the letterprepare_letter
I wrote the letter in Spanish. It asks for the full deposit within 30 days. Here is the preview. Check it before you say yes.
Letter previewPDF preview
Send it as a registered letter with signature for €8.90, or as a standard letter for €3.20?
As a registered letter, please.
Here is your order page. Check the letter there and pay. We print it only after the payment.
Order pagePaid: €8.90
Done, I paid.
Agent Letter DeskRead the letter's statusget_letter_status
Thank you. Your letter goes to print. Until printing starts, you can cancel it. Agent Letter Desk e-mails you when the post has it.
Did my letter arrive?
Agent Letter DeskRead the letter's statusget_letter_status
Correos has your letter. The tracking number is in your letter's status. The status does not show the delivery yet.
Your e-mail inbox
We e-mail you when Correos has your letter. You get the tracking number.
A few business days later
E-mail from Agent Letter Desk
Your letter is with the post
Correos has your letter to Javier Ortega Ruiz.
02Safeguards
An AI can make mistakes. We check each letter on our side, whatever the AI says.
Your AI shows you the letter, the preview and the price first. The letter waits for your approval.
A send with any other price is refused.
Each letter goes out once. A second copy only if you ask for one.
The sender is you. No AI can change the name.
Stop a prepared letter at any time, and a sent one until the printer starts on it.
03Destinations
To 30 European countries, Switzerland and the United Kingdom included, from Europe or the US, and within the United States. The recipient’s country decides the postal service.
What is recorded
For every letter, we record when the post receives it. What the post records after that depends on the service. Your AI tells you before you approve.
| Service | Handover recorded | Delivery recorded | Signature |
|---|---|---|---|
| Belgium: Registered letter (bpost recommandé / aangetekend) | Yes | Yes1 | No |
| Germany: Registered letter (Deutsche Post Einschreiben Einwurf) | Yes | Yes2 | No |
| Spain: Registered letter with signature (Correos carta certificada) | Yes | Yes | Yes |
| United States: Certified Mail with return receipt (USPS) | Yes | Yes | Yes |
| Standard letter (all countries) | Yes | No | No |
Registered letters come with a tracking number. We cannot fetch the post’s delivery receipt for you yet. Within Austria, we do not offer a registered letter yet: a letter to Austria goes as a standard letter.
| Recipient in | Service | Handover recorded | Delivery recorded | Signature | Business days | Price |
|---|---|---|---|---|---|---|
| Belgium | Registered letterbpost · recommandé / aangetekend | Yes | Yes (the record alone is not proof of delivery) | No | 1–2 | €13.90 |
| Standard letterbpost · Non-priority | Yes | No | No | 2–3 | €3.20 | |
| Germany | Registered letterDeutsche Post · Einschreiben Einwurf | Yes | Yes (the record alone is not proof of delivery) | No | 1 | €5.90 |
| Standard letterDeutsche Post · Economy | Yes | No | No | 2–3 | €2.20 | |
| Standard letterDeutsche Post · Standardbrief | Yes | No | No | 1 | €3.20 | |
| Spain | Registered letter with signatureCorreos · carta certificada | Yes | Yes | Yes | 2–4 | €8.90 |
| Standard letterCorreos · carta ordinaria | Yes | No | No | 2–4 | €3.20 |
* The record alone is not proof of delivery. See “What is recorded”.
| Recipient in | Service | Handover recorded | Delivery recorded | Signature | Business days | Price |
|---|---|---|---|---|---|---|
| Austria | Standard letterAustrian Post · Premium Brief | Yes | No | No | 1 | €3.20 |
| Luxembourg | Standard letterPost Luxembourg · Economy letter | Yes | No | No | 2–3 | €3.20 |
| Netherlands | Standard letterPostNL · Standaard | Yes | No | No | 1–2 | €3.20 |
| Switzerland | Standard letterSwiss Post · A Mail | Yes | No | No | 1 | €3.20 |
| United Kingdom | Standard letterRoyal Mail · 1st Class | Yes | No | No | 1 | €4.90 |
22 countries, 2–11 business days. Handover recorded; the delivery is not recorded.
| Recipient in | Service | Handover recorded | Delivery recorded | Signature | Business days | Price |
|---|---|---|---|---|---|---|
| United States | Certified Mail with return receiptUSPS · Certified Mail with electronic return receipt | Yes | Yes | Yes | 3–5 | $14.99 |
| Standard letterUSPS · First-Class Mail | Yes | No | No | 3–5 | $2.99 |
A letter within the United States needs a sender in the United States.
Prices
| Recipient in | Standard letter | Registered letter |
|---|---|---|
| Germany | from €2.20 | €5.90 |
| Austria | €3.20 | No |
| Switzerland | €3.20 | No |
| Belgium | €3.20 | €13.90 |
| Spain | €3.20 | €8.90 |
| 25 more countries in Europe | from €3.20 | No |
| United States | $2.99 | $14.99 |
+ €0.30 ($0.30) per extra page; exceptions below.
Prices for a one-page letter, with printing, postage and all fees. Before the launch, nothing is charged. No subscription, no account fee. From the launch, you pay per letter, after you approve the preview.
Each extra page adds €0.30 ($0.30 in the US), except: Austria, 4 pages €4.20; Belgium, registered letter, 9–10 pages €18.90; Cyprus, 9 pages €5.90; Germany, standard letter (2–3 business days), 9 pages €4.90; Malta, 9 pages €8.90, 10 pages €9.00; the Netherlands, 2 pages €3.90, 3 pages €4.90, 4 pages €5.10, 5–7 pages €5.90. A letter can have up to 10 pages, enclosures included (the Netherlands 7, the United States 5). Your AI shows the exact price of each letter before you approve it. Our print partner hands a letter to the post usually within two business days (in the United States: three). Business days are the post’s usual delivery times after the handover, not a guarantee.
Senders
A letter to Europe can come from any of 33 countries: the EU, Iceland, Liechtenstein, Norway, Switzerland, the United Kingdom and the United States. A letter to the United States needs a sender in the United States.
Undeliverable letters
If the post cannot deliver a letter in Europe, it returns the letter to our print partner, who destroys it unopened, and we e-mail you. In the United States, the post returns it to your sender address. Check the address in the preview before you approve.
If something goes wrong
From the launch:
04Connect
Agent Letter Desk is a remote MCP server. Add it to your AI app with this address.
Server URL
https://agentletterdesk.com/mcp
claude.ai, desktop and mobile
Or by hand: CustomizeConnectors+ AddAdd custom connector, then paste the server URL.
chatgpt.com
Worked on the Free plan when we checked (13 October 2026). OpenAI decides which plans can add one.
grok.com
chat.mistral.ai, formerly Le Chat
Works on the free plan.
Should also work, not tested by us yet: Gemini (US), Meta Muse (US; Canada later), Perplexity (paid plans).
You sign in with your e-mail address or your Google account. Before the launch, only invited testers can create an account. Everyone else can join the waitlist. On the consent page you can give read-only access: untick “Prepare, send and cancel letters”.
05For AI agents
Follow these steps for every letter. The server enforces the important ones.
Connect to the MCP server at https://agentletterdesk.com/mcp (Streamable HTTP). It uses OAuth 2.1: the user signs in on our page and approves the access.
Call get_account first. The sender of every letter is the account holder. Use the default sender address. If the account has no address, ask the user for it and call save_address.
Write the letter with the user. Ask the user for every name, number, date and address. Do not use placeholders or example values.
Call prepare_letter. It checks the letter, lays it out and returns a PDF preview link and the price.
Show the user the preview link, the recipient, the postal service and the price. Tell the user the note of the postal service: what it records and what it does not prove. A standard letter records only the handover, not the delivery.
Wait for the user’s clear yes. Do not call send_letter in the same answer as prepare_letter.
Call send_letter with the letter_id, the recipient name, the price and the number of enclosures that the user approved.
Give the user the status and the tracking number, if the service has one. Call cancel_letter if the user wants to stop the letter before printing.
Agent Letter Desk opens soon. Letters are not mailed yet. Tell the user that the letter does not go into the mail and that nothing is charged.
/llms.txtSummary for language models/llms-full.txtEvery fact: tools, routes, rules/mcp/server-cardMCP server card/eu.mdThis page as MarkdownGuides
No privacy contact or no answer?
Registered letter to Belgium from your AI app: bpost records the posting and the delivery.
Registered letter with signature to Spain from your AI app: Correos carta certificada for €8.90.
Withdraw within 14 days from a contract with a company in another EU country.
Renting in Germany?
What the post records for each of our services, and when that record alone is not proof of delivery: Germany, Belgium, Spain, the US, standard letters.
Add Agent Letter Desk to Claude once.
Connect once, ask ChatGPT, check the preview and price, say yes.
Ask your former landlord for your deposit by USPS Certified Mail.
Your gym contract says to cancel by mail?
06Privacy
The text of a letter and its enclosures stay on our server only until the letter reaches a final state: sent, failed, unresolved, cancelled or expired. Then they are deleted. We never store the PDF; the preview is drawn each time you open it. Our print partner keeps its own copy of a letter; the privacy policy says for how long. After sending, we keep the record that you need: recipient name, status, price and tracking number. The pages you are reading use no trackers and load nothing from other servers. They set cookies only when you choose a language or region.
07Opening soon
Agent Letter Desk opens soon. Until then, invited testers try every step: the letter, the preview, the price and the approval. No letter goes into the mail and nothing is charged. Paid mailing starts at the launch, with full terms.