Claude can send a paper letter for you through Agent Letter Desk, a connector that you add once. Claude writes the letter with you and shows you the preview and the price. Only after your yes do we print the letter, put it in an envelope and hand it to the post in your name. Letters go to 31 countries: the United States and 30 countries in Europe.
How it works
- Connect once. In Claude, open Customize, then Connectors, and select "Add custom connector". Enter the name Agent Letter Desk and the URL
https://agentletterdesk.com/mcp. Select Add, then Connect. Our sign-in page opens. Sign in with Google or with a code that we send by e-mail, enter your full name once, and allow the access. - Turn it on in a chat. Select the + button in the chat, then Connectors, and turn on Agent Letter Desk.
- Ask. Tell Claude who gets the letter, the address and what it must say. Claude asks for anything that is missing.
- Check the preview and the price. Claude shows a link to the PDF preview, the recipient, the postal service, what that service records and the price. The PDF is exactly what we print.
- Say yes. Claude asks for permission to use the send tool. Then we print and post the letter.
Example requests:
Write a letter to my landlord at [address]. The heating in my flat has not worked since Monday. Ask for a repair this week. Send it as a registered letter.
Send a GDPR access request to [company and address] by registered letter. They list no e-mail address for data protection requests.
On Claude's Free plan you can add one custom connector (Claude documentation).
Claude Code: run claude mcp add --transport http letter-desk https://agentletterdesk.com/mcp, then type /mcp and select Authenticate.
What our server enforces
These rules are checked by our server, not only by Claude:
- No letter goes out without a preview and a price.
- The send must match the price and the recipient that you saw.
- A send that comes seconds after the preview is refused. A person must have time to read.
- The same letter is not sent twice by mistake.
- The sender name comes from your account. Claude cannot change it.
Which service fits
| Service | What the post records | Where |
|---|---|---|
| Standard letter | The status shows when the letter was handed to the post. The post does not record the delivery. | All 31 countries (US: USPS First-Class Mail) |
| Registered letter | Deutsche Post records the drop into the mailbox, without the recipient's signature. On its own, not proof of delivery in court (see below). | Germany |
| Registered letter | bpost records the posting and the delivery. There is no signature. On its own, the receipt is proof of posting, not proof of delivery. Proof of delivery needs an acknowledgement of receipt (avis de réception). We do not offer it yet. | Belgium |
| Registered letter with signature | The post records the delivery and the recipient's signature. | Spain |
| Certified Mail with return receipt | USPS records the delivery and the signature. You can request the signed return receipt with the tracking number at usps.com. | United States |
Where a registered letter exists, it is the default; you can ask for a standard letter instead. Where none exists, for example to Austria or the United Kingdom, the preview names the service and says that the post does not record the delivery. More detail: Send a registered letter from ChatGPT.
What the German Einschreiben Einwurf proves in court. Deutsche Post records that the carrier put the letter into the mailbox. On its own, that is not firm proof of delivery: since May 2026, the modernised Einwurf-Einschreiben gives no prima facie proof of delivery, because the carrier confirms the drop on the scanner before putting the letter in (Federal Labour Court, 7 May 2026, 2 AZR 184/25, in German). In 2025 the court already held that the posting receipt and the online tracking status are not enough (2 AZR 68/24). We cannot fetch the post's delivery record for you yet. Where delivery must be proven, for example for a dismissal, people in Germany have a messenger deliver the letter as a witness, or have a bailiff serve it (§ 132 BGB).
Price
| Recipient in | Service | 1 page |
|---|---|---|
| United States | Certified Mail with return receipt (USPS) | $14.99 |
| United States | Standard letter (USPS First-Class Mail) | $2.99 |
| Belgium | Registered letter (bpost recommandé / aangetekend) | €13.90 |
| Belgium | Standard letter (bpost Non-priority) | €2.90 |
| Germany | Registered letter (Deutsche Post Einschreiben Einwurf) | €5.90 |
| Germany | Standard letter (Deutsche Post Standardbrief) | €2.90 |
| Spain | Registered letter with signature (Correos carta certificada) | €8.90 |
| Spain | Standard letter (Correos carta ordinaria) | €2.90 |
| Italy, Latvia and Norway | Standard letter | €3.90 |
| Ireland and United Kingdom | Standard letter | €4.90 |
| Malta | Standard letter | €5.90 |
| Austria, Luxembourg, Netherlands, Switzerland and 17 more European countries | Standard letter | €2.90 |
Longer letters cost more. The price depends on the country, the service and the number of pages; the preview shows the full price before you approve.
You pay the price that you approved: our server refuses a send with any other price. A letter to the United States needs a sender in the United States.
Delivery time
- Europe: printed and handed to the post on the same or the next business day. Then the post's usual time: 1 business day in Germany and Austria, more for countries served by DHL (see the table of destinations).
- United States: printed within 2 business days, then about 3–5 business days with USPS.
What you get afterwards
- Status: ask Claude at any time. It shows where the letter is: accepted, printing, or handed to the post.
- Tracking number: for registered mail, as soon as the post gives one. With it, you follow the delivery on the post's website.
- Cancel: you can stop a letter until it is printed.
- Planned: an e-mail at each step.
FAQ
Is Agent Letter Desk in Claude's connector directory?
Not yet. Add it by URL as a custom connector, as described above.
Can Claude send a letter without asking me?
Our server refuses a send that does not match the preview, the price and the recipient, or that comes seconds after the preview. Claude also asks before it uses the send tool. Do not choose "Always allow" for sending letters, so that you confirm each one.
Can I give Claude read-only access?
Yes. When you connect, untick "Prepare, send and cancel letters". Claude can then only read your account, your letters and their status.
Who is the sender?
You, the account holder. The name comes from your account and only you can change it, on the account page. The letter carries your typed name, not a handwritten signature.
Which letters are worth sending by post?
Letters where e-mail is not enough: the recipient has no e-mail address, you need proof that the letter arrived before a deadline, or a law or the recipient asks for a letter. Examples: a US credit report dispute or debt dispute by Certified Mail, a notice of a defect to a landlord in Germany, a GDPR request to a company without an online channel. More: When a letter is the right choice.
Which letters do not work?
Letters that need your handwritten signature, for example ending a job or a flat lease in Germany. Our letters carry your typed name. For these, let Claude write the text, then print, sign and post the letter yourself.
What happens to my letter text?
We keep it only until the letter reaches a final state, for example sent or cancelled. Then we delete it. We do not keep the PDF. See our privacy policy.
Not legal advice
Agent Letter Desk mails your letter. It does not give legal advice and does not promise a result.
Sources
Checked on 13 October 2026.
- Claude documentation: Add a connector that isn't in the directory
- Pingen: cut-off times
- USPS Domestic Mail Manual 503: Certified Mail, return receipt
- German Federal Labour Court: 2 AZR 184/25 (7 May 2026), beck-aktuell report, 2 AZR 68/24 (30 January 2025); § 132 BGB
- Prices: Agent Letter Desk v1 prices, decided 13 October 2026.
Use it with Claude, ChatGPT, Grok or Mistral Vibe
Add Agent Letter Desk to your AI app once, with this server URL: https://agentletterdesk.com/mcp
- Claude (claude.ai, desktop and mobile): Add to Claude opens Claude with the name and the URL filled in. Select Add, then Connect. Sign in and allow access, then turn the connector on in a chat. By hand: Settings › Connectors › Add custom connector, then paste the URL.
- ChatGPT (chatgpt.com): Plugins › Add › Add custom MCP server. Paste the URL, choose OAuth, sign in and allow access. Custom MCP servers are not available on every ChatGPT plan.
- Grok (grok.com): Plugins (Connectors) › New connector › Custom. Enter a name and paste the URL. Sign in and allow access in the window that opens. In a chat, type @ and pick Agent Letter Desk (Grok uses a connector only when you select it).
- Mistral Vibe (chat.mistral.ai, formerly Le Chat): Connectors › Add custom connector. Enter a name without spaces, such as AgentLetterDesk, and paste the URL. Sign in and allow access. In a chat, select + › Connectors › Agent Letter Desk (without this step, Mistral Vibe may write the letter itself). Works on the free plan.
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. Then ask your AI for the letter. You check the preview and the price. Nothing goes out without your yes.
Prices, destinations and the rules for every letter: All prices and destinations · How it works · Safeguards · Terms · Full facts for AI agents