Zetteldesk

Zetteldesk posts real physical letters directly from AI assistants with built-in format checks and German dispatch.

Zetteldesk allows users to send physical mail directly from AI assistants and automation platforms. The system checks PDFs for DIN 5008 compliance, prints them, and posts them in Germany. It works with assistants like Claude, ChatGPT, Claude Code, and Gemini, as well as platforms like Soforce via remote Model Context Protocol (MCP) servers with OAuth sign-in. Users can manage their balance, view letter status history, and automate recurring tasks such as invoices and payment reminders. Pricing is pay-per-letter with postage included, supported by a prepaid balance system using card, SEPA direct debit, or PayPal.

Zetteldesk at a glance

Best for: Founder, Support
Runs on: Web, API, CLI
Pricing: Prepaid balance from €10; letters from €1.12; standard plus registered mail €4.88; no subscription
Released: October 2026
Category: AI agent tool
Website: zetteldesk.com

Key features

Validate letter format and DIN 5008 compliance
Get exact price quotes before sending
Send physical letters with prepaid balance
Track letter status history
List all sent letters
Cancel letters and receive full refunds
Compose letters from plain text
Pre-signed upload for PDFs up to 20 MB

Use it for

Send invoices by post automatically
Send payment reminders and dunning letters
Process subscription cancellations and contract letters
Send confirmations, notices, and invitations
Submit written applications and mail to authorities

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