Echtpost for AI agents

EchtPost enables secure digital communication and encryption, giving businesses a reliable channel for sending confidential documents and messages that need extra privacy protection in transit. Connect it once through Arc0, and your agent, or Claude, ChatGPT and Cursor, can use it through one MCP endpoint, limited to what each user approved.

Connect Echtpost See the 1 actions ↓

DocumentsAPI keyMCP + RESTechtpost.de

AUDIT LOG · ECHTPOSTPOLICY: acme-support

09:41:07 · claude · u_8f2read

echtpost.list_templates

List templates✓ allowed · 212ms

EVERY ECHTPOST CALL, ON THE RECORD

01 · USE CASES

What agents do in Echtpost.

List message templates

List the templates available for a secure send before choosing one for a confidential letter.

Confirm template before sending

Have an agent confirm the correct template is selected before a confidential document goes out.

Read-only template browsing

Keep template listing read-only, since it only surfaces options without sending anything.

02 · ACTIONS

1 Echtpost actions, graded by risk.

Every Echtpost action is tagged read, write or destructive, so one policy covers the whole app and new actions inherit the right default.

read

Look things up. Allowed by default.

echtpost.list_templates
List templates

write

Create and change things. Allow, or ask the user first.

No write actions.

destructive

Delete, cancel or archive. Ask first, or deny outright.

No destructive actions.

03 · HOW IT WORKS

Echtpost in three steps.

01Your users connect EchtpostThey add their Echtpost api key on Arc0 Connect, under your brand. It goes straight into the vault.
02You set the rulesReads run, and writes like “updates” can wait for the user to approve.
03Any agent can actYour agent calls Echtpost through the Arc0 SDK or MCP, and so can Claude, ChatGPT and Cursor. Every call lands on the audit log.

POLICY.TS

await arc0.policies.set('echtpost', {
  read: 'allow',
  write: 'ask',        
  destructive: 'deny',  
})

# Claude Code: the same connection, one URL
$ claude mcp add --transport http arc0 \
    https://mcp.arc0.ai/u/u_8f2

04 · AUTH AND DATA

How Echtpost connects.

Users add their Echtpost api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

The same Echtpost connection serves your agent over MCP and your own backend over REST and the proxy, so a user connects once. How Arc0 handles credentials →

AUTH: API key
CREDENTIALS: Per-tenant encrypted vault
MODEL SEES: Results only, never credentials
AUDIT LOG: Every call, on every plan

05 · WORKS WITH

Use Echtpost from any agent.

Claude

ChatGPT

Cursor

Codex

VS Code

OpenAI Agents SDK

Claude Agent SDK

Vercel AI SDK

Mastra

LangGraph

06 · RELATED

Echtpost and Arc0, answered.

Q01

Can I use Echtpost with Claude, ChatGPT or Cursor?

Yes. Connect Echtpost to Arc0 once, then add your Arc0 MCP URL to Claude, ChatGPT, Cursor, Claude Code or any other remote-MCP client. Each assistant only gets the Echtpost actions you allow.

Q02

How do users connect Echtpost?

Users add their Echtpost api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

Q03

Which Echtpost actions can my agent take?

1 in total: 1 read, 0 write and 0 destructive. Your policies decide which of them each agent may call.

Q04

Can I make my agent read-only in Echtpost?

Yes. Allow read actions and deny writes in the Echtpost policy. Your agent can still look things up, and any write it attempts is blocked and logged.

Q05

Can my own backend call Echtpost too?

Yes. The same Echtpost connection is available over REST and through the Arc0 proxy, so your product and your agent share one connection per user.

Get started

Plug Echtpost into your agent.

Your users connect Echtpost once, under your brand. Your agent gets 1 actions behind your policies, with every call on the record.

Connect Echtpost Browse all apps →

Free to build · MCP + REST · Audit log on every plan